mongo/debian/mongod.1

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.TH "MONGOD" "1" "Jun 21, 2018" "4.0" "mongodb-manual"
.SH NAME
mongod \- MongoDB Server
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.SS On this page
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\fI\%Synopsis\fP
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\fI\%Options\fP
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\fI\%Core Options\fP
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\fI\%Free Monitoring\fP
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\fI\%LDAP Authentication or Authorization Options\fP
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\fI\%Storage Options\fP
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\fI\%WiredTiger Options\fP
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\fI\%Replication Options\fP
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\fI\%Sharded Cluster Options\fP
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\fI\%TLS/SSL Options\fP
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.SH SYNOPSIS
.sp
\fI\%mongod\fP is the primary daemon process for the MongoDB
system. It handles data requests, manages data access, and performs
background management operations.
.sp
This document provides a complete overview of all command line options
for \fI\%mongod\fP\&. These command line options are primarily useful
for testing: In common operation, use the configuration file
options to control the behavior of
your database.
.sp
\fBNOTE:\fP
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Starting in version 4.0, MongoDB disables support for TLS 1.0
encryption on systems where TLS 1.1+ is available. For
more details, see 4.0\-disable\-tls\&.
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.SH OPTIONS
.SS Core Options
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.B \-\-help, \-h
Returns information on the options and use of \fBmongod\fP\&.
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.B \-\-version
Returns the \fBmongod\fP release number.
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.B \-\-config <filename>, \-f <filename>
Specifies a configuration file for runtime configuration options. The
configuration file is the preferred method for runtime configuration of
\fBmongod\fP\&. The options are equivalent to the command\-line
configuration options. See /reference/configuration\-options for
more information.
.sp
Ensure the configuration file uses ASCII encoding. The \fBmongod\fP
instance does not support configuration files with non\-ASCII encoding,
including UTF\-8.
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.B \-\-verbose, \-v
Increases the amount of internal reporting returned on standard output
or in log files. Increase the verbosity with the \fB\-v\fP form by
including the option multiple times, (e.g. \fB\-vvvvv\fP\&.)
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.B \-\-quiet
Runs \fBmongod\fP in a quiet mode that attempts to limit the amount
of output.
.sp
This option suppresses:
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output from database commands
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replication activity
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connection accepted events
.IP \(bu 2
connection closed events
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.B \-\-port <port>
\fIDefault\fP: 27017
.sp
Specifies the TCP port on which the MongoDB instance listens for
client connections.
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.B \-\-bind_ip <ip address>
\fIDefault\fP: localhost
.sp
\fBNOTE:\fP
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.INDENT 3.5
Starting in MongoDB 3.6, \fBmongod\fP bind to localhost
(\fB127.0.0.1\fP) by default. See 3.6\-bind\-to\-localhost\&.
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The IP addresses and/or full Unix domain socket paths on which
\fBmongod\fP should listen for client connections. You may attach
\fBmongod\fP to any interface. To bind to multiple addresses, enter a
list of comma\-separated values.
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.SS Example
.sp
\fBlocalhost,/tmp/mongod.sock\fP
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.sp
\fBWARNING:\fP
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Before you bind to other ip addresses, consider enabling
access control and other security measures listed
in /administration/security\-checklist to prevent unauthorized
access.
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.sp
To bind to all IPv4 addresses, enter \fB0.0.0.0\fP\&.
.sp
To bind to all IPv4 and IPv6 addresses, enter \fB0.0.0.0,::\fP
or alternatively, use the \fBnet.bindIpAll\fP setting.
.sp
\fBNOTE:\fP
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\fB\-\-bind_ip\fP and \fB\-\-bind_ip_all\fP are mutually exclusive. That
is, you can specify one or the other, but not both.
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.B \-\-bind_ip_all
New in version 3.6.

.sp
If specified, the \fBmongod\fP instance binds to all ip addresses. When
attaching \fBmongod\fP to a publicly accessible interface, ensure
that you have implemented proper authentication and firewall
restrictions to protect the integrity of your database.
.sp
\fBWARNING:\fP
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Before you bind to other ip addresses, consider enabling
access control and other security measures listed
in /administration/security\-checklist to prevent unauthorized
access.
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.sp
Alternatively, you can set the \fB\-\-bind_ip\fP option to
\fB0.0.0.0,::\fP to bind to all IP addresses.
.sp
\fBNOTE:\fP
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\fB\-\-bind_ip\fP and \fB\-\-bind_ip_all\fP are mutually exclusive. That
is, you can specify one or the other, but not both.
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.B \-\-ipv6
Enables IPv6 support. \fBmongod\fP disables IPv6 support by default.
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.B \-\-listenBacklog <number>
\fIDefault\fP: Target system \fBSOMAXCONN\fP constant
.sp
New in version 3.6.

.sp
The maximum number of connections that can exist in the listen
queue.
.sp
\fBWARNING:\fP
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Consult your local system’s documentation to understand the
limitations and configuration requirements before using this
parameter.
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\fBIMPORTANT:\fP
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To prevent undefined behavior, specify a value for this
parameter between \fB1\fP and the local system \fBSOMAXCONN\fP
constant.
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.sp
The default value for the \fBlistenBacklog\fP parameter is set at
compile time to the target system \fBSOMAXCONN\fP constant.
\fBSOMAXCONN\fP is the maximum valid value that is documented for
the \fIbacklog\fP parameter to the \fIlisten\fP system call.
.sp
Some systems may interpret \fBSOMAXCONN\fP symbolically, and others
numerically. The actual \fIlisten backlog\fP applied in practice may
differ from any numeric interpretation of the \fBSOMAXCONN\fP constant
or argument to \fB\-\-listenBacklog\fP, and may also be constrained by
system settings like \fBnet.core.somaxconn\fP on Linux.
.sp
Passing a value for the \fBlistenBacklog\fP parameter that exceeds the
\fBSOMAXCONN\fP constant for the local system is, by the letter of the
standards, undefined behavior. Higher values may be silently integer
truncated, may be ignored, may cause unexpected resource
consumption, or have other adverse consequences.
.sp
On systems with workloads that exhibit connection spikes, for which
it is empirically known that the local system can honor higher
values for the \fIbacklog\fP parameter than the \fBSOMAXCONN\fP constant,
setting the \fBlistenBacklog\fP parameter to a higher value may reduce
operation latency as observed by the client by reducing the number
of connections which are forced into a backoff state.
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.B \-\-maxConns <number>
The maximum number of simultaneous connections that \fBmongod\fP will
accept. This setting has no effect if it is higher than your operating
system’s configured maximum connection tracking threshold.
.sp
Do not assign too low of a value to this option, or you will
encounter errors during normal application operation.
.sp
\fBNOTE:\fP
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Changed in version 2.6: MongoDB removed the upward limit on the \fBmaxIncomingConnections\fP
setting.

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.B \-\-logpath <path>
Sends all diagnostic logging information to a log file instead of to
standard output or to the host’s syslog system. MongoDB creates
the log file at the path you specify.
.sp
By default, MongoDB will move any existing log file rather than overwrite
it. To instead append to the log file, set the \fI\%\-\-logappend\fP option.
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.B \-\-syslog
Sends all logging output to the host’s syslog system rather
than to standard output or to a log file. , as with \fI\%\-\-logpath\fP\&.
.sp
The \fI\%\-\-syslog\fP option is not supported on Windows.
.sp
\fBWARNING:\fP
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The \fBsyslog\fP daemon generates timestamps when it logs a message, not
when MongoDB issues the message. This can lead to misleading timestamps
for log entries, especially when the system is under heavy load. We
recommend using the \fI\%\-\-logpath\fP option for production systems to
ensure accurate timestamps.
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.B \-\-syslogFacility <string>
\fIDefault\fP: user
.sp
Specifies the facility level used when logging messages to syslog.
The value you specify must be supported by your
operating system’s implementation of syslog. To use this option, you
must  enable the \fI\%\-\-syslog\fP option.
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.B \-\-logappend
Appends new entries to the end of the existing log file when the \fBmongod\fP
instance restarts. Without this option, \fI\%mongod\fP will back up the
existing log and create a new file.
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.B \-\-logRotate <string>
\fIDefault\fP: rename
.sp
New in version 3.0.0.

.sp
Determines the behavior for the \fBlogRotate\fP command.
Specify either \fBrename\fP or \fBreopen\fP:
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\fBrename\fP renames the log file.
.IP \(bu 2
\fBreopen\fP closes and reopens the log file following the typical
Linux/Unix log rotate behavior. Use \fBreopen\fP when using the
Linux/Unix logrotate utility to avoid log loss.
.sp
If you specify \fBreopen\fP, you must also use \fI\%\-\-logappend\fP\&.
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.B \-\-timeStampFormat <string>
\fIDefault\fP: iso8601\-local
.sp
The time format for timestamps in log messages. Specify one of the
following values:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBctime\fP
T}	T{
Displays timestamps as \fBWed Dec 31
18:17:54.811\fP\&.
T}
_
T{
\fBiso8601\-utc\fP
T}	T{
Displays timestamps in Coordinated Universal Time (UTC) in the
ISO\-8601 format. For example, for New York at the start of the
Epoch: \fB1970\-01\-01T00:00:00.000Z\fP
T}
_
T{
\fBiso8601\-local\fP
T}	T{
Displays timestamps in local time in the ISO\-8601
format. For example, for New York at the start of the Epoch:
\fB1969\-12\-31T19:00:00.000\-0500\fP
T}
_
.TE
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.B \-\-traceExceptions
For internal diagnostic use only.
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.B \-\-pidfilepath <path>
Specifies a file location to hold the process ID of the \fBmongod\fP
process where \fBmongod\fP will write its PID. This is useful for
tracking the \fBmongod\fP process in combination with
the \fI\%\-\-fork\fP option. Without a specified \fI\%\-\-pidfilepath\fP option, the
process creates no PID file.
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.B \-\-keyFile <file>
Specifies the path to a key file that stores the shared secret
that MongoDB instances use to authenticate to each other in a
sharded cluster or replica set\&. \fI\%\-\-keyFile\fP implies
\fI\%\-\-auth\fP\&. See inter\-process\-auth for more
information.
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.B \-\-setParameter <options>
Specifies one of the MongoDB parameters described in
/reference/parameters\&. You can specify multiple \fBsetParameter\fP
fields.
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.B \-\-nounixsocket
Disables listening on the UNIX domain socket. \fI\%\-\-nounixsocket\fP applies only
to Unix\-based systems.
.sp
The \fBmongod\fP process
always listens on the UNIX socket unless one of the following is true:
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.IP \(bu 2
\fI\%\-\-nounixsocket\fP is set
.IP \(bu 2
\fBnet.bindIp\fP is not set
.IP \(bu 2
\fBnet.bindIp\fP does not specify \fB127.0.0.1\fP
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.sp
New in version 2.6: \fBmongod\fP installed from official \&.deb and \&.rpm packages
have the \fBbind_ip\fP configuration set to \fB127.0.0.1\fP by
default.

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.B \-\-unixSocketPrefix <path>
\fIDefault\fP: /tmp
.sp
The path for the UNIX socket. \fI\%\-\-unixSocketPrefix\fP applies only
to Unix\-based systems.
.sp
If this option has no value, the
\fBmongod\fP process creates a socket with \fB/tmp\fP as a prefix. MongoDB
creates and listens on a UNIX socket unless one of the following is true:
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.IP \(bu 2
\fBnet.unixDomainSocket.enabled\fP is \fBfalse\fP
.IP \(bu 2
\fI\%\-\-nounixsocket\fP is set
.IP \(bu 2
\fBnet.bindIp\fP is not set
.IP \(bu 2
\fBnet.bindIp\fP does not specify \fB127.0.0.1\fP
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.B \-\-filePermissions <path>
\fIDefault\fP: \fB0700\fP
.sp
Sets the permission for the UNIX domain socket file.
.sp
\fI\%\-\-filePermissions\fP applies only to Unix\-based systems.
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.B \-\-fork
Enables a daemon mode that runs the \fBmongod\fP process in the
background. By default \fBmongod\fP does not run as a daemon:
typically you will run \fBmongod\fP as a daemon, either by using
\fI\%\-\-fork\fP or by using a controlling process that handles the
daemonization process (e.g. as with \fBupstart\fP and \fBsystemd\fP).
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.B \-\-auth
Enables authorization to control user’s access to database resources
and operations. When authorization is enabled, MongoDB requires all
clients to authenticate themselves first in order to determine the
access for the client.
.sp
Configure users via the mongo shell\&. If no users exist, the localhost interface
will continue to have access to the database until you create
the first user.
.sp
See Security
for more information.
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.B \-\-noauth
Disables authentication. Currently the default. Exists for future
compatibility and clarity.
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.B \-\-transitionToAuth
New in version 3.4: Allows the \fBmongod\fP to accept and create authenticated and
non\-authenticated connections to and from other \fI\%mongod\fP
and \fBmongos\fP instances in the deployment. Used for
performing rolling transition of replica sets or sharded clusters
from a no\-auth configuration to internal authentication\&. Requires specifying a internal
authentication mechanism such as
\fI\%\-\-keyFile\fP\&.

.sp
For example, if using keyfiles for
internal authentication, the \fBmongod\fP creates
an authenticated connection with any \fI\%mongod\fP or \fBmongos\fP
in the deployment using a matching keyfile. If the security mechanisms do
not match, the \fBmongod\fP utilizes a non\-authenticated connection instead.
.sp
A \fBmongod\fP running with \fI\%\-\-transitionToAuth\fP does not enforce user access
controls\&. Users may connect to your deployment without any
access control checks and perform read, write, and administrative operations.
.sp
\fBNOTE:\fP
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A \fBmongod\fP running with internal authentication and \fIwithout\fP \fI\%\-\-transitionToAuth\fP requires clients to connect
using user access controls\&. Update clients to
connect to the \fBmongod\fP using the appropriate user
prior to restarting \fBmongod\fP without \fI\%\-\-transitionToAuth\fP\&.
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.B \-\-cpu
Forces the \fBmongod\fP process to report the percentage of CPU time in
write lock, every four seconds.
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.B \-\-sysinfo
Returns diagnostic system information and then exits. The
information provides the page size, the number of physical pages,
and the number of available physical pages.
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.B \-\-noscripting
Disables the scripting engine.
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.B \-\-notablescan
Forbids operations that require a collection scan. See \fBnotablescan\fP for additional information.
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.B \-\-shutdown
The \fI\%\-\-shutdown\fP option cleanly and safely terminates the \fBmongod\fP
process. When invoking \fBmongod\fP with this option you must set the
\fI\%\-\-dbpath\fP option either directly or by way of the
configuration file and the
\fI\%\-\-config\fP option.
.sp
The \fI\%\-\-shutdown\fP option is available only on Linux systems.
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.B \-\-redactClientLogData
New in version 3.4: Available in MongoDB Enterprise only.

.sp
A \fBmongod\fP running with \fI\%\-\-redactClientLogData\fP redacts any message accompanying a given
log event before logging. This prevents the \fBmongod\fP from writing
potentially sensitive data stored on the database to the diagnostic log.
Metadata such as error or operation codes, line numbers, and source file
names are still visible in the logs.
.sp
Use \fI\%\-\-redactClientLogData\fP in conjunction with encryption to assist compliance with regulatory
requirements.
.sp
For example, a MongoDB deployment might store Personally Identifiable
Information (PII) in one or more collections. The \fBmongod\fP logs events
such as those related to CRUD operations, sharding metadata, etc. It is
possible that the \fBmongod\fP may expose PII as a part of these logging
operations. A \fBmongod\fP running with \fI\%\-\-redactClientLogData\fP removes any message
accompanying these events before being output to the log, effectively
removing the PII.
.sp
Diagnostics on a \fBmongod\fP running with \fI\%\-\-redactClientLogData\fP may be more difficult
due to the lack of data related to a log event. See the
process logging manual page for an
example of the effect of \fI\%\-\-redactClientLogData\fP on log output.
.sp
You can enable or disable log redaction on a running \fBmongod\fP
using the \fBsetParameter\fP database command.
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.sp
.nf
.ft C
db.adminCommand(
  { setParameter: 1, redactClientLogData : true | false }
)
.ft P
.fi
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.B \-\-networkMessageCompressors <string>
New in version 3.4.

.sp
.INDENT 7.0
Changed in version 3.6: .IP \(bu 2
Add support for zlib compressor.
.IP \(bu 2
Enabled by default. To disable, set to \fBdisabled\fP\&.
.UNINDENT

.sp
Enables network compression for communication between this
\fBmongod\fP instance and:
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.IP \(bu 2
other members of the replica set, if the instance is part of a
replica set
.IP \(bu 2
other members of the sharded cluster, if the instance is part of a
sharded cluster
.IP \(bu 2
a \fBmongo\fP shell,
.IP \(bu 2
drivers that support the \fBOP_COMPRESSED\fP message format.
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\fBIMPORTANT:\fP
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Messages are compressed when both parties enable network
compression. Otherwise, messages between the parties are
uncompressed.
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You can specify the following compressors:
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snappy (Default)
.IP \(bu 2
zlib
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.sp
If you specify multiple compressors, then the order in which you list
the compressors matter as well as the communication initiator. For
example, if a \fBmongo\fP shell specifies the following network
compressors \fBzlib,snappy\fP and the \fI\%mongod\fP specifies
\fBsnappy,zlib\fP, messages between \fBmongo\fP shell and
\fI\%mongod\fP uses \fBzlib\fP\&.
.sp
If the parties do not share at least one common compressor, messages
between the parties are uncompressed. For example, if a
\fBmongo\fP shell specifies the network compressor
\fBzlib\fP and \fI\%mongod\fP specifies \fBsnappy\fP, messages
between \fBmongo\fP shell and \fI\%mongod\fP are not compressed.
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.B \-\-timeZoneInfo <path>
The full path from which to load the time zone database. If this option
is not provided, then MongoDB will use its built\-in time zone database.
.sp
The configuration file included with Linux and macOS packages sets the time
zone database path to \fB/usr/share/zoneinfo\fP by default.
.sp
The built\-in time zone database is a copy of the \fI\%Olson/IANA time zone
database\fP\&. It is updated along with MongoDB
releases, but the release cycle of the time zone database differs from the
release cycle of MongoDB. A copy of the most recent release of the time zone
database can be downloaded from
\fI\%https://downloads.mongodb.org/olson_tz_db/timezonedb\-latest.zip\fP\&.
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.sp
.nf
.ft C
wget https://downloads.mongodb.org/olson_tz_db/timezonedb\-latest.zip
unzip timezonedb\-latest.zip
mongod \-\-timeZoneInfo timezonedb\-2017b/
.ft P
.fi
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\fBSEE ALSO:\fP
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\fBprocessManagement.timeZoneInfo\fP\&.
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.B \-\-serviceExecutor <string>
\fIDefault\fP: synchronous
.sp
New in version 3.6.

.sp
Determines the threading and execution model \fBmongod\fP uses to
execute client requests. The \fB\-\-serviceExecutor\fP option accepts one
of the following values:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBsynchronous\fP
T}	T{
The \fBmongod\fP uses synchronous networking and manages its
networking thread pool on a per connection basis. Previous
versions of MongoDB managed threads in this way.
T}
_
T{
\fBadaptive\fP
T}	T{
The \fBmongod\fP uses the new experimental asynchronous
networking mode with an adaptive thread pool which manages
threads on a per request basis. This mode should have more
consistent performance and use less resources when there are
more inactive connections than database requests.
T}
_
.TE
.UNINDENT
.SS Free Monitoring
.sp
New in version 4.0.

.INDENT 0.0
.TP
.B \-\-enableFreeMonitoring <runtime|on|off>
New in version 4.0: Available for MongoDB Community Edition.

.sp
Enables or disables free MongoDB Cloud monitoring\&. \fI\%\-\-enableFreeMonitoring\fP accepts the following
values:
.TS
center;
|l|l|.
_
T{
\fBruntime\fP
T}	T{
Default. You can enable or disable free monitoring during
runtime.
.sp
To enable or disable free monitoring during runtime, see
\fBdb.enableFreeMonitoring()\fP and
\fBdb.disableFreeMonitoring()\fP\&.
.sp
To enable or disable free monitoring during runtime when
running with access control, users must have required
privileges. See \fBdb.enableFreeMonitoring()\fP and
\fBdb.disableFreeMonitoring()\fP for details.
T}
_
T{
\fBon\fP
T}	T{
Enables free monitoring at startup; i.e. registers for free
monitoring. When enabled at startup, you cannot disable free
monitoring during runtime.
T}
_
T{
\fBoff\fP
T}	T{
Disables free monitoring at startup, regardless of whether
you have previously registered for free monitoring.  When disabled at startup,
you cannot enable free monitoring during runtime.
T}
_
.TE
.sp
Once enabled, the free monitoring state remains enabled until
explicitly disabled. That is, you do not need to re\-enable each time
you start the server.
.sp
For the corresponding configuration file setting, see
\fBcloud.monitoring.free.state\fP\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-enableFreeMonitoringTag <string>
New in version 4.0: Available for MongoDB Community Edition.

.sp
Optional tag to describe environment context. The tag can be sent as
part of the free MongoDB Cloud monitoring registration at start up.
.sp
For the corresponding configuration file setting, see
\fBcloud.monitoring.free.tag\fP\&.
.UNINDENT
.SS LDAP Authentication or Authorization Options
.INDENT 0.0
.TP
.B \-\-ldapServers <host1>:<port>,<host2>:<port>,...,<hostN>:<port>
New in version 3.4: Available in MongoDB Enterprise only.

.sp
The LDAP server against which the \fBmongod\fP executes LDAP operations
against to authenticate users or determine what actions a user is authorized
to perform on a given database. If the LDAP server specified has any
replicated instances, you may specify the host and port of each replicated
server in a comma\-delimited list.
.sp
If your LDAP infrastrucure partitions the LDAP directory over multiple LDAP
servers, specify \fIone\fP LDAP server any of its replicated instances to
\fI\%\-\-ldapServers\fP\&. MongoDB supports following LDAP referrals as defined in \fI\%RFC 4511
4.1.10\fP\&. Do not use \fI\%\-\-ldapServers\fP
for listing every LDAP server in your infrastucture.
.sp
This setting can be configured on a running \fBmongod\fP using
\fBsetParameter\fP\&.
.sp
If unset, \fBmongod\fP cannot use LDAP authentication or authorization\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-ldapQueryUser <string>
New in version 3.4: Available in MongoDB Enterprise only.

.sp
The identity with which \fBmongod\fP binds as, when connecting to or
performing queries on an LDAP server.
.sp
Only required if any of the following are true:
.INDENT 7.0
.IP \(bu 2
Using LDAP authorization\&.
.IP \(bu 2
Using an LDAP query for \fI\%username transformation\fP\&.
.IP \(bu 2
The LDAP server disallows anonymous binds
.UNINDENT
.sp
You must use \fI\%\-\-ldapQueryUser\fP with \fI\%\-\-ldapQueryPassword\fP\&.
.sp
If unset, \fBmongod\fP will not attempt to bind to the LDAP server.
.sp
This setting can be configured on a running \fBmongod\fP using
\fBsetParameter\fP\&.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
Windows MongoDB deployments can use \fI\%\-\-ldapBindWithOSDefaults\fP
instead of \fI\%\-\-ldapQueryUser\fP and \fI\%\-\-ldapQueryPassword\fP\&. You cannot specify
both \fI\%\-\-ldapQueryUser\fP and \fI\%\-\-ldapBindWithOSDefaults\fP at the same time.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-ldapQueryPassword <string>
New in version 3.4: Available in MongoDB Enterprise only.
.sp
The password used to bind to an LDAP server when using
\fI\%\-\-ldapQueryUser\fP\&. You must use \fI\%\-\-ldapQueryPassword\fP with
\fI\%\-\-ldapQueryUser\fP\&.

.sp
If unset, \fBmongod\fP will not attempt to bind to the LDAP server.
.sp
This setting can be configured on a running \fBmongod\fP using
\fBsetParameter\fP\&.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
Windows MongoDB deployments can use \fI\%\-\-ldapBindWithOSDefaults\fP
instead of \fI\%\-\-ldapQueryPassword\fP and \fI\%\-\-ldapQueryPassword\fP\&. You cannot specify
both \fI\%\-\-ldapQueryPassword\fP and \fI\%\-\-ldapBindWithOSDefaults\fP at the same time.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-ldapBindWithOSDefaults <bool>
\fIDefault\fP: False
.sp
New in version 3.4: Available in MongoDB Enterprise for the Windows platform only.

.sp
Allows \fBmongod\fP to authenticate, or bind, using your Windows login
credentials when connecting to the LDAP server.
.sp
Only required if:
.INDENT 7.0
.IP \(bu 2
Using LDAP authorization\&.
.IP \(bu 2
Using an LDAP query for \fI\%username transformation\fP\&.
.IP \(bu 2
The LDAP server disallows anonymous binds
.UNINDENT
.sp
Use \fI\%\-\-ldapBindWithOSDefaults\fP to replace \fI\%\-\-ldapQueryUser\fP and
\fI\%\-\-ldapQueryPassword\fP\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-ldapBindMethod <string>
\fIDefault\fP: simple
.sp
New in version 3.4: Available in MongoDB Enterprise only.

.sp
The method \fBmongod\fP uses to authenticate to an LDAP server.
Use with \fI\%\-\-ldapQueryUser\fP and \fI\%\-\-ldapQueryPassword\fP to
connect to the LDAP server.
.sp
\fI\%\-\-ldapBindMethod\fP supports the following values:
.INDENT 7.0
.IP \(bu 2
\fBsimple\fP \- \fBmongod\fP uses simple authentication.
.IP \(bu 2
\fBsasl\fP \- \fBmongod\fP uses SASL protocol for authentication
.UNINDENT
.sp
If you specify \fBsasl\fP, you can configure the available SASL mechanisms
using \fI\%\-\-ldapBindSASLMechanisms\fP\&. \fBmongod\fP defaults to
using \fBDIGEST\-MD5\fP mechanism.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-ldapBindSASLMechanisms <string>
\fIDefault\fP: DIGEST\-MD5
.sp
New in version 3.4: Available in MongoDB Enterprise only.

.sp
A comma\-separated list of SASL mechanisms \fBmongod\fP can
use when authenticating to the LDAP server. The \fBmongod\fP and the
LDAP server must agree on at least one mechanism. The \fBmongod\fP
dynamically loads any SASL mechanism libraries installed on the host
machine at runtime.
.sp
Install and configure the appropriate libraries for the selected
SASL mechanism(s) on both the \fBmongod\fP host and the remote
LDAP server host. Your operating system may include certain SASL
libraries by default. Defer to the documentation associated with each
SASL mechanism for guidance on installation and configuration.
.sp
If using the \fBGSSAPI\fP SASL mechanism for use with
security\-kerberos, verify the following for the
\fBmongod\fP host machine:
.INDENT 7.0
.TP
.B \fBLinux\fP
.INDENT 7.0
.IP \(bu 2
The \fBKRB5_CLIENT_KTNAME\fP environment
variable resolves to the name of the client keytab\-files
for the host machine. For more on Kerberos environment
variables, please defer to the
\fI\%Kerberos documentation\fP\&.
.IP \(bu 2
The client keytab includes a
kerberos\-user\-principal for the \fBmongod\fP to use when
connecting to the LDAP server and execute LDAP queries.
.UNINDENT
.TP
.B \fBWindows\fP
If connecting to an Active Directory server, the Windows
Kerberos configuration automatically generates a
\fI\%Ticket\-Granting\-Ticket\fP
when the user logs onto the system. Set \fI\%\-\-ldapBindWithOSDefaults\fP to
\fBtrue\fP to allow \fBmongod\fP to use the generated credentials when
connecting to the Active Directory server and execute queries.
.UNINDENT
.sp
Set \fI\%\-\-ldapBindMethod\fP to \fBsasl\fP to use this option.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
For a complete list of SASL mechanisms see the
\fI\%IANA listing\fP\&.
Defer to the documentation for your LDAP or Active Directory
service for identifying the SASL mechanisms compatible with the
service.
.sp
MongoDB is not a source of SASL mechanism libraries, nor
is the MongoDB documentation a definitive source for
installing or configuring any given SASL mechanism. For
documentation and support, defer to the SASL mechanism
library vendor or owner.
.sp
For more information on SASL, defer to the following resources:
.INDENT 0.0
.IP \(bu 2
For Linux, please see the \fI\%Cyrus SASL documentation\fP\&.
.IP \(bu 2
For Windows, please see the \fI\%Windows SASL documentation\fP\&.
.UNINDENT
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-ldapTransportSecurity <string>
\fIDefault\fP: tls
.sp
New in version 3.4: Available in MongoDB Enterprise only.

.sp
By default, \fBmongod\fP creates a TLS/SSL secured connection to the LDAP
server.
.sp
For Linux deployments, you must configure the appropriate TLS Options in
\fB/etc/openldap/ldap.conf\fP file. Your operating system’s package manager
creates this file as part of the MongoDB Enterprise installation, via the
\fBlibldap\fP dependency. See the documentation for \fBTLS Options\fP in the
\fI\%ldap.conf OpenLDAP documentation\fP
for more complete instructions.
.sp
For Windows deployment, you must add the LDAP server CA certificates to the
Windows certificate management tool. The exact name and functionality of the
tool may vary depending on operating system version. Please see the
documentation for your version of Windows for more information on
certificate management.
.sp
Set \fI\%\-\-ldapTransportSecurity\fP to \fBnone\fP to disable TLS/SSL between \fBmongod\fP and the LDAP
server.
.sp
\fBWARNING:\fP
.INDENT 7.0
.INDENT 3.5
Setting \fI\%\-\-ldapTransportSecurity\fP to \fBnone\fP transmits plaintext information and possibly
credentials between \fBmongod\fP and the LDAP server.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-ldapTimeoutMS <long>
\fIDefault\fP: 10000
.sp
New in version 3.4: Available in MongoDB Enterprise only.

.sp
The amount of time in milliseconds \fBmongod\fP should wait for an LDAP server
to respond to a request.
.sp
Increasing the value of \fI\%\-\-ldapTimeoutMS\fP may prevent connection failure between the
MongoDB server and the LDAP server, if the source of the failure is a
connection timeout. Decreasing the value of \fI\%\-\-ldapTimeoutMS\fP reduces the time
MongoDB waits for a response from the LDAP server.
.sp
This setting can be configured on a running \fBmongod\fP using
\fBsetParameter\fP\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-ldapUserToDNMapping <string>
New in version 3.4: Available in MongoDB Enterprise only.

.sp
Maps the username provided to \fBmongod\fP for authentication to a LDAP
Distinguished Name (DN). You may need to use \fI\%\-\-ldapUserToDNMapping\fP to transform a
username into an LDAP DN in the following scenarios:
.INDENT 7.0
.IP \(bu 2
Performing LDAP authentication with simple LDAP binding, where users
authenticate to MongoDB with usernames that are not full LDAP DNs.
.IP \(bu 2
Using an \fI\%LDAP authorization query template\fP that requires a DN.
.IP \(bu 2
Transforming the usernames of clients authenticating to Mongo DB using
different authentication mechanisms (e.g. x.509, kerberos) to a full LDAP
DN for authorization.
.UNINDENT
.sp
\fI\%\-\-ldapUserToDNMapping\fP expects a quote\-enclosed JSON\-string representing an ordered array
of documents. Each document contains a regular expression \fBmatch\fP and
either a \fBsubstitution\fP or \fBldapQuery\fP template used for transforming the
incoming username.
.sp
Each document in the array has the following form:
.INDENT 7.0
.INDENT 3.5
.sp
.nf
.ft C
{
  match: "<regex>"
  substitution: "<LDAP DN>" | ldapQuery: "<LDAP Query>"
}
.ft P
.fi
.UNINDENT
.UNINDENT
.TS
center;
|l|l|l|.
_
T{
Field
T}	T{
Description
T}	T{
Example
T}
_
T{
\fBmatch\fP
T}	T{
An ECMAScript\-formatted regular expression (regex) to match against a
provided username. Each parenthesis\-enclosed section represents a
regex capture group used by \fBsubstitution\fP or \fBldapQuery\fP\&.
T}	T{
\fB"(.+)ENGINEERING"\fP
\fB"(.+)DBA"\fP
T}
_
T{
\fBsubstitution\fP
T}	T{
An LDAP distinguished name (DN) formatting template that converts the
authentication name matched by the \fBmatch\fP regex into a LDAP DN.
Each curly bracket\-enclosed numeric value is replaced by the
corresponding \fI\%regex capture group\fP extracted
from the authentication username via the \fBmatch\fP regex.
T}	T{
\fB"cn={0},ou=engineering,
dc=example,dc=com"\fP
T}
_
T{
\fBldapQuery\fP
T}	T{
A LDAP query formatting template that inserts the authentication
name matched by the \fBmatch\fP regex into an LDAP query URI encoded
respecting RFC4515 and RFC4516. Each curly bracket\-enclosed numeric
value is replaced by the corresponding \fI\%regex capture group\fP extracted
from the authentication username via the \fBmatch\fP expression.
\fBmongod\fP executes the query against the LDAP server to retrieve
the LDAP DN for the authenticated user. \fBmongod\fP requires
exactly one returned result for the transformation to be
successful, or \fBmongod\fP skips this transformation.
T}	T{
\fB"ou=engineering,dc=example,
dc=com??one?(user={0})"\fP
T}
_
.TE
.sp
For each document in the array, you must use either \fBsubstitution\fP or
\fBldapQuery\fP\&. You \fIcannot\fP specify both in the same document.
.sp
When performing authentication or authorization, \fBmongod\fP steps through
each document in the array in the given order, checking the authentication
username against the \fBmatch\fP filter.  If a match is found,
\fBmongod\fP applies the transformation and uses the output for
authenticating the user. \fBmongod\fP does not check the remaining documents
in the array.
.sp
If the given document does not match the provided authentication name, or
the transformation described by the document fails, \fBmongod\fP continues
through the list of documents to find additional matches. If no matches are
found in any document, \fBmongod\fP returns an error.
.INDENT 7.0
.INDENT 3.5
.SS Example
.sp
The following shows two transformation documents. The first
document matches against any string ending in \fB@ENGINEERING\fP, placing
anything preceeding the suffix into a regex capture group. The
second document matches against any string ending in \fB@DBA\fP, placing
anything preceeding the suffix into a regex capture group.
.sp
\fBIMPORTANT:\fP
.INDENT 0.0
.INDENT 3.5
You must pass the array to \fI\%\-\-ldapUserToDNMapping\fP as a string.
.UNINDENT
.UNINDENT
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
"[
   {
      match: "(.+)@ENGINEERING.EXAMPLE.COM",
      substitution: "cn={0},ou=engineering,dc=example,dc=com"
   },
   {
      match: "(.+)@DBA.EXAMPLE.COM",
      ldapQuery: "ou=dba,dc=example,dc=com??one?(user={0})"

   }

]"
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
A user with username \fBalice@ENGINEERING.EXAMPLE.COM\fP matches the first
document. The regex capture group \fB{0}\fP corresponds to the string
\fBalice\fP\&. The resulting output is the DN
\fB"cn=alice,ou=engineering,dc=example,dc=com"\fP\&.
.sp
A user with username \fBbob@DBA.EXAMPLE.COM\fP matches the second document.
The regex capture group \fB{0}\fP corresponds to the string \fBbob\fP\&.  The
resulting output is the LDAP query
\fB"ou=dba,dc=example,dc=com??one?(user=bob)"\fP\&. \fBmongod\fP executes this
query against the LDAP server, returning the result
\fB"cn=bob,ou=dba,dc=example,dc=com"\fP\&.
.UNINDENT
.UNINDENT
.sp
If \fI\%\-\-ldapUserToDNMapping\fP is unset, \fBmongod\fP applies no transformations to the username
when attempting to authenticate or authorize a user against the LDAP server.
.sp
This setting can be configured on a running \fBmongod\fP using the
\fBsetParameter\fP database command.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
An explanation of \fI\%RFC4515\fP,
\fI\%RFC4516\fP or LDAP queries is out
of scope for the MongoDB Documentation. Please review the RFC directly or
use your preferred LDAP resource.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-ldapAuthzQueryTemplate <string>
New in version 3.4: Available in MongoDB Enterprise only.

.sp
A relative LDAP query URL formatted conforming to \fI\%RFC4515\fP and \fI\%RFC4516\fP that \fBmongod\fP executes to obtain
the LDAP groups to which the authenticated user belongs to. The query is
relative to the host or hosts specified in \fI\%\-\-ldapServers\fP\&.
.sp
Use the \fB{USER}\fP placeholder in the URL to substitute the authenticated
username, or the transformed username if a \fI\%username mapping\fP is specified.
.sp
When constructing the query URL, ensure that the order of LDAP parameters
respects RFC4516:
.INDENT 7.0
.INDENT 3.5
.sp
.nf
.ft C
[ dn  [ ? [attributes] [ ? [scope] [ ? [filter] [ ? [Extensions] ] ] ] ] ]
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
If your query includes an attribute, \fBmongod\fP assumes that the query
retrieves a the DNs which this entity is member of.
.sp
If your query does not include an attribute, \fBmongod\fP assumes
the query retrieves all entities which the user is member of.
.sp
For each LDAP DN returned by the query, \fBmongod\fP assigns the authorized
user a corresponding role on the \fBadmin\fP database. If a role on the on the
\fBadmin\fP database exactly matches the DN, \fBmongod\fP grants the user the
roles and privileges assigned to that role. See the
\fBdb.createRole()\fP method for more information on creating roles.
.INDENT 7.0
.INDENT 3.5
.SS Example
.sp
This LDAP query returns any groups listed in the LDAP user object’s
\fBmemberOf\fP attribute.
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
"{USER}?memberOf?base"
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
Your LDAP configuration may not include the \fBmemberOf\fP attribute as part
of the user schema, may possess a different attribute for reporting group
membership, or may not track group membership through attributes.
Configure your query with respect to your own unique LDAP configuration.
.UNINDENT
.UNINDENT
.sp
If unset, \fBmongod\fP cannot authorize users using LDAP.
.sp
This setting can be configured on a running \fBmongod\fP using the
\fBsetParameter\fP database command.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
An explanation of \fI\%RFC4515\fP,
\fI\%RFC4516\fP or LDAP queries is out
of scope for the MongoDB Documentation. Please review the RFC directly or
use your preferred LDAP resource.
.UNINDENT
.UNINDENT
.UNINDENT
.SS Storage Options
.INDENT 0.0
.TP
.B \-\-storageEngine string
\fIDefault\fP: \fBwiredTiger\fP
.sp
Changed in version 4.0: MongoDB deprecates the MMAPv1 storage engine.

.sp
Specifies the storage engine for the \fBmongod\fP database. Available
values include:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBwiredTiger\fP
T}	T{
To specify the /core/wiredtiger\&.
T}
_
T{
\fBinMemory\fP
T}	T{
To specify the /core/inmemory\&.
.sp
New in version 3.2: Available in MongoDB Enterprise only.
T}
_
T{
\fBmmapv1\fP (Deprecated in MongoDB 4.0)
T}	T{
To specify the /core/mmapv1\&.
T}
_
.TE
.sp
If you attempt to start a \fBmongod\fP with a
\fI\%\-\-dbpath\fP that contains data files produced by a
storage engine other than the one specified by \fI\%\-\-storageEngine\fP, \fBmongod\fP
will refuse to start.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-dbpath <path>
\fIDefault\fP: \fB/data/db\fP on Linux and macOS, \fB\edata\edb\fP on Windows
.sp
The directory where the \fBmongod\fP instance stores its data.
.sp
If you
installed MongoDB using a package management system, check the
\fB/etc/mongod.conf\fP file provided by your packages to see the
directory is specified.
.sp
Changed in version 3.0: The files in \fI\%\-\-dbpath\fP must correspond to the storage engine
specified in \fI\%\-\-storageEngine\fP\&. If the data files do not
correspond to \fI\%\-\-storageEngine\fP, \fBmongod\fP will refuse to
start.

.UNINDENT
.INDENT 0.0
.TP
.B \-\-directoryperdb
Uses a separate directory to store data for each database. The
directories are under the \fI\%\-\-dbpath\fP directory, and each subdirectory
name corresponds to the database name.
.sp
Changed in version 3.0: To change the \fI\%\-\-directoryperdb\fP option for existing deployments, you must
restart the \fI\%mongod\fP instances with the new \fI\%\-\-directoryperdb\fP
value \fBand\fP a new data directory (\fI\%\-\-dbpath <new path>\fP), and then
repopulate the data.
.INDENT 7.0
.IP \(bu 2
For standalone instances, you can use \fBmongodump\fP on
the existing instance, stop the instance, restart with the new
\fI\%\-\-directoryperdb\fP value \fBand\fP a new data directory, and use
\fBmongorestore\fP to populate the new data directory.
.IP \(bu 2
For replica sets, you can update in a rolling manner by stopping
a secondary member, restart with the new \fI\%\-\-directoryperdb\fP value \fBand\fP
a new data directory, and use initial sync to populate the new data directory.
To update all members, start with the secondary members first.
Then step down the primary, and update the stepped\-down member.
.UNINDENT

.sp
Not available for \fI\%mongod\fP instances that use the
in\-memory storage engine\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-noIndexBuildRetry
Changed in version 4.0: \fI\%\-\-noIndexBuildRetry\fP cannot be used in
conjunction with \fI\%\-\-replSet\fP\&.

.sp
Stops the \fBmongod\fP standalone instance from rebuilding incomplete indexes on the next
start up. This applies in cases where the \fBmongod\fP restarts after it
has shut down or stopped in the middle of an index build. In such cases,
the \fBmongod\fP always removes any incomplete indexes, and then also, by
default, attempts to rebuild them. To stop the \fBmongod\fP from
rebuilding incomplete indexes on start up, include this option on the
command\-line.
.sp
Not available for \fI\%mongod\fP instances that use the
in\-memory storage engine\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-noprealloc
Deprecated since version 2.6: By default, MongoDB does not preallocate data files. The option
exists for compatibility and clarity.

.sp
Disables the preallocation of data files.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-nssize <value>
\fIDefault\fP: 16
.sp
Specifies the default size for namespace files, which are files that end
in \fB\&.ns\fP\&. Each collection and index counts as a namespace.
.sp
Use this setting to control size for newly created namespace files. This
option has no impact on existing files. The maximum size for a namespace
file is 2047 megabytes. The default value of 16 megabytes provides for
approximately 24,000 namespaces.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-quota
Enables a maximum limit for the number data files each database can
have. When running with the \fI\%\-\-quota\fP option, MongoDB has a maximum of 8
data files per database. Adjust the quota with
\fI\%\-\-quotaFiles\fP\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-quotaFiles <number>
\fIDefault\fP: 8
.sp
Modifies the limit on the number of data files per database. \fI\%\-\-quotaFiles\fP
option requires that you set \fI\%\-\-quota\fP\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-smallfiles
Sets MongoDB to use a smaller default file size. The \fI\%\-\-smallfiles\fP option
reduces the initial size for data files and limits the maximum size to
512 megabytes. \fI\%\-\-smallfiles\fP also reduces the size of each journal
file from 1 gigabyte to 128 megabytes. Use \fI\%\-\-smallfiles\fP if you have a large
number of databases that each holds a small quantity of data.
.sp
The \fI\%\-\-smallfiles\fP option can lead the \fBmongod\fP instance to create a large
number of files, which can affect performance for larger databases.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-syncdelay <value>
\fIDefault\fP: 60
.sp
Controls how much time can pass before MongoDB flushes data to the data
files via an fsync operation.
.sp
\fBDo not set this value on
production systems.\fP In almost every situation, you should use the
default setting.
.sp
\fBWARNING:\fP
.INDENT 7.0
.INDENT 3.5
If you set \fI\%\-\-syncdelay\fP to \fB0\fP, MongoDB will not sync the
memory mapped files to disk.
.UNINDENT
.UNINDENT
.sp
The \fBmongod\fP process writes data very quickly to the journal and
lazily to the data files. \fI\%\-\-syncdelay\fP has no effect on the
\fBjournal\fP files or journaling,
but if \fI\%\-\-syncdelay\fP is set to \fB0\fP the journal will eventually consume
all available disk space. If you set \fI\%\-\-syncdelay\fP to \fB0\fP for testing
purposes, you should also set \fI\%\-\-nojournal\fP
to \fBtrue\fP\&.
.sp
The \fBserverStatus\fP command reports the background flush
thread’s status via the \fBbackgroundFlushing\fP field.
.sp
Not available for \fI\%mongod\fP instances that use the
in\-memory storage engine\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-upgrade
Upgrades the on\-disk data format of the files specified by the
\fI\%\-\-dbpath\fP to the latest version, if needed.
.sp
This option only affects the operation of the \fBmongod\fP if the data
files are in an old format.
.sp
In most cases you should not set this value, so you can exercise the
most control over your upgrade process. See the MongoDB \fI\%release notes\fP (on the download page) for more
information about the upgrade process.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-repair
Runs a repair routine on all databases. This is equivalent
to shutting down and running the \fBrepairDatabase\fP database
command on all databases.
.sp
\fBWARNING:\fP
.INDENT 7.0
.INDENT 3.5
.INDENT 0.0
.IP \(bu 2
Before using \fBrepairDatabase\fP, make a backup copy of
the dbpath directory.
.IP \(bu 2
Avoid running \fBrepairDatabase\fP against a replica set.
If you are trying to repair a replica set member, and you
have access to an intact copy of your data (e.g. a recent backup
or an intact member of the replica set), you should
restore from that intact copy (see
/tutorial/resync\-replica\-set\-member), and \fBnot\fP use
\fBrepairDatabase\fP\&.
.IP \(bu 2
Only use the \fBrepairDatabase\fP command and associated
wrappers, including \fBdb.repairDatabase()\fP and
\fI\%mongod \-\-repair\fP, if you have no other options. These
operations remove and do not save any corrupt data during the
repair process.
.UNINDENT
.UNINDENT
.UNINDENT
.sp
If you are running with journaling enabled, there is
almost never any need to run \fBrepairDatabase\fP unless you
need to recover from a disk\-level data corruption. In the event of an
unclean shutdown, the server will be able to restore the data files to
a clean state automatically.
.sp
Changed in version 2.1.2.

.sp
If you run the repair option \fIand\fP have data in a journal file, the
\fBmongod\fP instance refuses to start. In these cases you should start
the \fBmongod\fP without the \fI\%\-\-repair\fP option, which allows the
\fBmongod\fP to recover data from the journal. This completes more
quickly and is more likely to produce valid data files. To continue the
repair operation despite the journal files, shut down the \fBmongod\fP
cleanly and restart with the \fI\%\-\-repair\fP option.
.sp
The \fI\%\-\-repair\fP option copies data from the source data files into new data
files in the \fBrepairPath\fP and then replaces the original data
files with the repaired data files.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-repairpath <path>
\fIDefault\fP: A \fB_tmp_repairDatabase_<num>\fP directory under the
\fBdbPath\fP\&.
.sp
Specifies a working directory that MongoDB will use during the
\fI\%\-\-repair\fP operation. When \fB\-\-repair\fP completes, the
\fI\%\-\-repairpath\fP directory is empty, and
\fBdbPath\fP contains the repaired files.
.sp
The \fI\%\-\-repairpath\fP must be within the \fBdbPath\fP\&. You can
specify a symlink to \fI\%\-\-repairpath\fP to use a path on a different file
system.
.sp
Only available for \fI\%mongod\fP instance using the MMAPv1 storage engine.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-journal
Enables the durability journal to ensure data files remain valid
and recoverable. This option applies only when you specify the
\fI\%\-\-dbpath\fP option. \fBmongod\fP enables journaling by default.
.sp
Not available for \fI\%mongod\fP instances that use the
in\-memory storage engine\&.
.sp
If any voting member of a replica set uses the in\-memory
storage engine, you must set
\fBwriteConcernMajorityJournalDefault\fP to \fBfalse\fP\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-nojournal
Disables journaling\&. \fBmongod\fP
enables journaling by default.
.sp
Not available for \fI\%mongod\fP instances that use the
in\-memory storage engine\&.
.sp
Starting in MongoDB 4.0, you cannot specify \fI\%\-\-nojournal\fP option or \fBstorage.journal.enabled:
false\fP for replica set members that use the
WiredTiger storage engine.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-journalOptions <arguments>
Provides functionality for testing. Not for general use, and will affect data
file integrity in the case of abnormal system shutdown.
.sp
Not available for \fI\%mongod\fP instances that use the
in\-memory storage engine\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-journalCommitInterval <value>
\fIDefault\fP: 100 or 30
.sp
Changed in version 3.2.

.sp
The maximum amount of time in milliseconds that
the \fBmongod\fP process allows between
journal operations. Values can range from 1 to 500 milliseconds. Lower
values increase the durability of the journal, at the expense of disk
performance.  The default journal commit interval is 100 milliseconds.
.sp
On MMAPv1, if the journal is on a different block device (e.g. physical
volume, RAID device, or LVM volume) than the data files, the default journal
commit interval is 30 milliseconds. Additionally, on MMAPv1, when a write
operation with \fBj:true\fP is pending, \fBmongod\fP will reduce
\fBcommitIntervalMs\fP to a third of the set value.
.sp
On WiredTiger, the default journal commit interval is 100 milliseconds. Additionally,
a write with \fBj:true\fP will cause an immediate sync of the journal.
.sp
Not available for \fI\%mongod\fP instances that use the
in\-memory storage engine\&.
.UNINDENT
.SS WiredTiger Options
.INDENT 0.0
.TP
.B \-\-wiredTigerCacheSizeGB float
Defines the maximum size of the internal cache that WiredTiger will
use for all data.
.sp
Changed in version 3.4: Values can range from 256MB to 10TB and can be a float. In
addition, the default value has also changed.

.sp
Starting in 3.4, the WiredTiger internal cache, by default, will use
the larger of either:
.INDENT 7.0
.IP \(bu 2
50% of (RAM \- 1 GB), or
.IP \(bu 2
256 MB.
.UNINDENT
.sp
For example, on a system with a total of 4GB of RAM the WiredTiger
cache will use 1.5GB of RAM (\fB0.5 * (4 GB \- 1 GB) = 1.5 GB\fP).
Conversely, a system with a total of 1.25 GB of RAM will allocate 256
MB to the WiredTiger cache because that is more than half of the
total RAM minus one gigabyte (\fB0.5 * (1.25 GB \- 1 GB) = 128 MB < 256 MB\fP).
.sp
Avoid increasing the WiredTiger internal cache size above its
default value.
.sp
With WiredTiger, MongoDB utilizes both the WiredTiger internal cache
and the filesystem cache.
.sp
Via the filesystem cache, MongoDB automatically uses all free memory
that is not used by the WiredTiger cache or by other processes.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
The \fI\%\-\-wiredTigerCacheSizeGB\fP limits the size of the WiredTiger internal
cache. The operating system will use the available free memory
for filesystem cache, which allows the compressed MongoDB data
files to stay in memory. In addition, the operating system will
use any free RAM to buffer file system blocks and file system
cache.
.sp
To accommodate the additional consumers of RAM, you may have to
decrease WiredTiger internal cache size.
.UNINDENT
.UNINDENT
.sp
The default WiredTiger internal cache size value assumes that there is a
single \fI\%mongod\fP instance per machine. If a single machine
contains multiple MongoDB instances, then you should decrease the setting to
accommodate the other \fI\%mongod\fP
instances.
.sp
If you run \fI\%mongod\fP in a container (e.g. \fBlxc\fP,
\fBcgroups\fP, Docker, etc.) that does \fInot\fP have access to all of the
RAM available in a system, you must set \fI\%\-\-wiredTigerCacheSizeGB\fP to a value less
than the amount of RAM available in the container. The exact amount
depends on the other processes running in the container.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-wiredTigerJournalCompressor <compressor>
\fIDefault\fP: snappy
.sp
New in version 3.0.0.

.sp
Specifies the type of compression to use to compress WiredTiger
journal data.
.sp
Available compressors are:
.INDENT 7.0
.IP \(bu 2
\fBnone\fP
.IP \(bu 2
snappy
.IP \(bu 2
zlib
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-wiredTigerDirectoryForIndexes
New in version 3.0.0.

.sp
When you start \fBmongod\fP with \fI\%\-\-wiredTigerDirectoryForIndexes\fP, \fBmongod\fP stores indexes and collections in separate
subdirectories under the data (i.e. \fI\%\-\-dbpath\fP) directory.
Specifically, \fBmongod\fP stores the indexes in a subdirectory named
\fBindex\fP and the collection data in a subdirectory named
\fBcollection\fP\&.
.sp
By using a symbolic link, you can specify a different location for
the indexes. Specifically, when \fI\%mongod\fP instance is \fBnot\fP
running, move the \fBindex\fP subdirectory to the destination and
create a symbolic link named \fBindex\fP under the data directory to
the new destination.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-wiredTigerCollectionBlockCompressor <compressor>
\fIDefault\fP: snappy
.sp
New in version 3.0.0.

.sp
Specifies the default type of compression to use to compress collection
data. You can override this on a per\-collection basis when creating
collections.
.sp
Available compressors are:
.INDENT 7.0
.IP \(bu 2
\fBnone\fP
.IP \(bu 2
snappy
.IP \(bu 2
zlib
.UNINDENT
.sp
\fI\%\-\-wiredTigerCollectionBlockCompressor\fP affects all collections created. If you change
the value of \fI\%\-\-wiredTigerCollectionBlockCompressor\fP on an existing MongoDB deployment, all new
collections will use the specified compressor. Existing collections
will continue to use the compressor specified when they were
created, or the default compressor at that time.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-wiredTigerIndexPrefixCompression <boolean>
\fIDefault\fP: true
.sp
New in version 3.0.0.

.sp
Enables or disables prefix compression for index data.
.sp
Specify \fBtrue\fP for \fI\%\-\-wiredTigerIndexPrefixCompression\fP to enable prefix compression for
index data, or \fBfalse\fP to disable prefix compression for index data.
.sp
The \fI\%\-\-wiredTigerIndexPrefixCompression\fP setting affects all indexes created. If you change
the value of \fI\%\-\-wiredTigerIndexPrefixCompression\fP on an existing MongoDB deployment, all new
indexes will use prefix compression. Existing indexes
are not affected.
.UNINDENT
.SS Replication Options
.INDENT 0.0
.TP
.B \-\-replSet <setname>
Configures replication. Specify a replica set name as an argument to
this set. All hosts in the replica set must have the same set name.
.sp
Starting in MongoDB 4.0,
.INDENT 7.0
.IP \(bu 2
\fI\%\-\-replSet\fP cannot be used in conjunction with
\fI\%\-\-noIndexBuildRetry\fP\&.
.IP \(bu 2
For the WiredTiger storage engine, \fI\%\-\-replSet\fP cannot be used in
conjunction with \fI\%\-\-nojournal\fP\&.
.UNINDENT
.sp
If your application connects to more than one replica set, each set
should have a distinct name. Some drivers group replica set
connections by replica set name.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-oplogSize <value>
Specifies a maximum size in megabytes for the replication operation log
(i.e., the oplog). The \fBmongod\fP process creates an
oplog based on the maximum amount of space available. For 64\-bit
systems, the oplog is typically 5% of available disk space.
.sp
Once the \fBmongod\fP has created the oplog for the first time,
changing the \fI\%\-\-oplogSize\fP option will not affect the size of the oplog.
Use the \fBreplSetResizeOplog\fP administrative command to
change the oplog size of a running \fBmongod\fP replica set member.
\fBreplSetResizeOplog\fP enables you to resize the oplog
dynamically without restarting the \fI\%mongod\fP process.
.sp
See replica\-set\-oplog\-sizing for more information.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-replIndexPrefetch
\fIDefault\fP: all
.INDENT 7.0
.INDENT 3.5
.IP "Storage Engine Specific Feature"
.sp
\fI\%\-\-replIndexPrefetch\fP is only available with the \fBmmapv1\fP
storage engine.
.UNINDENT
.UNINDENT
.sp
Determines which indexes secondary members of a replica
set load into memory before applying operations from the oplog. By
default secondaries load all indexes related to an operation into memory
before applying operations from the oplog.
.sp
Set this option to one of the following:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBnone\fP
T}	T{
Secondaries do not load indexes into memory.
T}
_
T{
\fBall\fP
T}	T{
Secondaries load all indexes related to an operation.
T}
_
T{
\fB_id_only\fP
T}	T{
Secondaries load no additional indexes into memory beyond the
already existing \fB_id\fP index.
T}
_
.TE
.UNINDENT
.INDENT 0.0
.TP
.B \-\-enableMajorityReadConcern
Deprecated since version 3.6: Starting in MongoDB 3.6, \fB"majority"\fP read concern
is always enabled, and this option has no effect.

.UNINDENT
.SS Sharded Cluster Options
.INDENT 0.0
.TP
.B \-\-configsvr
\fIRequired if starting a config server.\fP
.sp
Declares that this \fBmongod\fP instance serves as the config
server of a sharded cluster. When
running with this option, clients (i.e. other cluster components)
cannot write data to any database other than \fBconfig\fP
and \fBadmin\fP\&. The default port for a \fBmongod\fP with this option is
\fB27019\fP and the default \fI\%\-\-dbpath\fP directory is
\fB/data/configdb\fP, unless specified.
.sp
\fBIMPORTANT:\fP
.INDENT 7.0
.INDENT 3.5
Starting in 3.4, you must deploy config servers as a replica set.
The use of the deprecated mirrored \fI\%mongod\fP instances as
config servers (SCCC) is no longer supported.
.sp
The replica set config servers (CSRS) must run the
WiredTiger storage engine\&.
.UNINDENT
.UNINDENT
.sp
The \fI\%\-\-configsvr\fP option creates a local oplog\&.
.sp
Do not use the \fI\%\-\-configsvr\fP option with \fI\%\-\-shardsvr\fP\&. Config
servers cannot be a shard server.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-configsvrMode <string>
\fBAvailable in MongoDB 3.2 version only\fP
.sp
If set to \fBsccc\fP, indicates that the config servers are deployed
as three mirrored \fI\%mongod\fP instances, even if one or more
config servers is also a member of a replica set. \fBconfigsvrMode\fP
only accepts the value \fBsccc\fP\&.
.sp
If unset, config servers running as replica sets expect to use the
“config server replica set” protocol for writing to config servers,
rather than the “mirrored mongod” write protocol.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-shardsvr
\fIRequired if starting a shard server.\fP
.sp
Configures this \fBmongod\fP instance as a shard in a
sharded cluster. The default port for these instances is
\fB27018\fP\&.
.sp
\fBIMPORTANT:\fP
.INDENT 7.0
.INDENT 3.5
Changed in version 3.6.

.sp
You must deploy shards as replica sets. See the \fI\%\-\-replSet\fP
option to deploy \fBmongod\fP as part of a replica set.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-moveParanoia
If specified, during chunk migration, a shard saves,
to the \fBmoveChunk\fP directory of the \fB\-\-dbpath\fP, all documents
migrated from that shard.
.sp
MongoDB does not automatically delete the data saved in the
\fBmoveChunk\fP directory.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-noMoveParanoia
Changed in version 3.2: Starting in 3.2, MongoDB uses \fB\-\-noMoveParanoia\fP as the default.

.sp
During chunk migration, a shard does not save documents migrated from
the shard.
.UNINDENT
.SS TLS/SSL Options
.INDENT 0.0
.INDENT 3.5
.SS See
.sp
/tutorial/configure\-ssl for full
documentation of MongoDB’s support.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslOnNormalPorts
Deprecated since version 2.6: Use \fI\%\-\-sslMode requireSSL\fP instead.

.sp
Enables TLS/SSL for \fBmongod\fP\&.
.sp
With \fI\%\-\-sslOnNormalPorts\fP, a \fBmongod\fP requires TLS/SSL encryption for all
connections on the default MongoDB port, or the port specified by
\fI\%\-\-port\fP\&. By default, \fI\%\-\-sslOnNormalPorts\fP is
disabled.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslMode <mode>
New in version 2.6.

.sp
Enables TLS/SSL or mixed TLS/SSL used for all network connections. The
argument to the \fI\%\-\-sslMode\fP option can be one of the following:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBdisabled\fP
T}	T{
The server does not use TLS/SSL.
T}
_
T{
\fBallowSSL\fP
T}	T{
Connections between servers do not use TLS/SSL. For incoming
connections, the server accepts both TLS/SSL and non\-TLS/non\-SSL.
T}
_
T{
\fBpreferSSL\fP
T}	T{
Connections between servers use TLS/SSL. For incoming
connections, the server accepts both TLS/SSL and non\-TLS/non\-SSL.
T}
_
T{
\fBrequireSSL\fP
T}	T{
The server uses and accepts only TLS/SSL encrypted connections.
T}
_
.TE
.sp
Starting in version 3.4, if \fB\-\-sslCAFile\fP or \fBssl.CAFile\fP is not
specified and you are not using x.509 authentication, the
system\-wide CA certificate store will be used when connecting to an
TLS/SSL\-enabled server.
.sp
If using x.509 authentication, \fB\-\-sslCAFile\fP or \fBssl.CAFile\fP
must be specified.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslPEMKeyFile <filename>
Specifies the \fB\&.pem\fP file that contains both the TLS/SSL certificate
and key. Specify the file name of the \fB\&.pem\fP file using relative
or absolute paths.
.sp
You must specify \fI\%\-\-sslPEMKeyFile\fP when TLS/SSL is enabled.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslPEMKeyPassword <value>
Specifies the password to de\-crypt the certificate\-key file (i.e.
\fI\%\-\-sslPEMKeyFile\fP). Use the \fI\%\-\-sslPEMKeyPassword\fP option only if the
certificate\-key file is encrypted. In all cases, the \fBmongod\fP will
redact the password from all logging and reporting output.
.sp
Changed in version 2.6: If the private key in the PEM file is encrypted and you do not
specify the \fI\%\-\-sslPEMKeyPassword\fP option, the \fBmongod\fP will prompt for a
passphrase. See ssl\-certificate\-password\&.

.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-clusterAuthMode <option>
\fIDefault\fP: keyFile
.sp
New in version 2.6.

.sp
The authentication mode used for cluster authentication. If you use
internal x.509 authentication,
specify so here. This option can have one of the following values:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBkeyFile\fP
T}	T{
Use a keyfile for authentication.
Accept only keyfiles.
T}
_
T{
\fBsendKeyFile\fP
T}	T{
For rolling upgrade purposes. Send a keyfile for
authentication but can accept both keyfiles and x.509
certificates.
T}
_
T{
\fBsendX509\fP
T}	T{
For rolling upgrade purposes. Send the x.509 certificate for
authentication but can accept both keyfiles and x.509
certificates.
T}
_
T{
\fBx509\fP
T}	T{
Recommended. Send the x.509 certificate for authentication and
accept only x.509 certificates.
T}
_
.TE
.sp
Starting in version 3.4, if \fB\-\-sslCAFile\fP or \fBssl.CAFile\fP is not
specified and you are not using x.509 authentication, the
system\-wide CA certificate store will be used when connecting to an
TLS/SSL\-enabled server.
.sp
If using x.509 authentication, \fB\-\-sslCAFile\fP or \fBssl.CAFile\fP
must be specified.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslClusterFile <filename>
New in version 2.6.

.sp
Specifies the \fB\&.pem\fP file that contains the x.509 certificate\-key
file for membership authentication
for the cluster or replica set.
.sp
If \fI\%\-\-sslClusterFile\fP does not specify the \fB\&.pem\fP file for internal cluster
authentication, the cluster uses the \fB\&.pem\fP file specified in the
\fI\%\-\-sslPEMKeyFile\fP option.
.sp
If using x.509 authentication, \fB\-\-sslCAFile\fP or \fBssl.CAFile\fP
must be specified.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslClusterPassword <value>
New in version 2.6.

.sp
Specifies the password to de\-crypt the x.509 certificate\-key file
specified with \fB\-\-sslClusterFile\fP\&. Use the \fI\%\-\-sslClusterPassword\fP option only
if the certificate\-key file is encrypted. In all cases, the \fBmongod\fP
will redact the password from all logging and reporting output.
.sp
If the x.509 key file is encrypted and you do not specify the
\fI\%\-\-sslClusterPassword\fP option, the \fBmongod\fP will prompt for a passphrase. See
ssl\-certificate\-password\&.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslCAFile <filename>
Specifies the \fB\&.pem\fP file that contains the root certificate chain
from the Certificate Authority. Specify the file name of the
\fB\&.pem\fP file using relative or absolute paths.
.sp
Starting in version 3.4, if \fB\-\-sslCAFile\fP or \fBssl.CAFile\fP is not
specified and you are not using x.509 authentication, the
system\-wide CA certificate store will be used when connecting to an
TLS/SSL\-enabled server.
.sp
If using x.509 authentication, \fB\-\-sslCAFile\fP or \fBssl.CAFile\fP
must be specified.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslCRLFile <filename>
Specifies the the \fB\&.pem\fP file that contains the Certificate Revocation
List. Specify the file name of the \fB\&.pem\fP file using relative or
absolute paths.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslAllowInvalidCertificates
Bypasses the validation checks for TLS/SSL certificates on other
servers in the cluster and allows the use of invalid certificates to
connect.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
Starting in MongoDB 4.0, if you specify
\fB\-\-sslAllowInvalidCertificates\fP or \fBssl.allowInvalidCertificates:
true\fP when using x.509 authentication, an invalid certificate is
only sufficient to establish a TLS/SSL connection but is
\fIinsufficient\fP for authentication.
.UNINDENT
.UNINDENT
.sp
When using
the \fI\%\-\-sslAllowInvalidCertificates\fP setting, MongoDB
logs a warning regarding the use of the invalid certificate.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslAllowInvalidHostnames
New in version 3.0.

.sp
Disables the validation of the hostnames in TLS/SSL certificates,
when connecting to other members of the replica set or sharded cluster
for inter\-process authentication. This allows \fBmongod\fP to connect
to other members if the hostnames in their certificates do not match
their configured hostname.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslAllowConnectionsWithoutCertificates
Disables the requirement for TLS/SSL certificate validation that
\fB\-\-sslCAFile\fP enables. With the \fI\%\-\-sslAllowConnectionsWithoutCertificates\fP option, the \fBmongod\fP
will accept connections when the client does not present a certificate
when establishing the connection.
.sp
If the client presents a certificate and the \fBmongod\fP has \fI\%\-\-sslAllowConnectionsWithoutCertificates\fP
enabled, the \fBmongod\fP will validate the certificate using the root
certificate chain specified by \fB\-\-sslCAFile\fP and reject clients
with invalid certificates.
.sp
Use the \fI\%\-\-sslAllowConnectionsWithoutCertificates\fP option if you have a mixed deployment that includes
clients that do not or cannot present certificates to the \fBmongod\fP\&.
.sp
For more information about TLS/SSL and MongoDB, see
/tutorial/configure\-ssl and
/tutorial/configure\-ssl\-clients .
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslDisabledProtocols <protocol(s)>
New in version 3.0.7.

.sp
Prevents a MongoDB server running with TLS/SSL from accepting
incoming connections that use a specific protocol or protocols. To
specify multiple protocols, use a comma separated list of protocols.
.sp
\fI\%\-\-sslDisabledProtocols\fP recognizes the following protocols: \fBTLS1_0\fP, \fBTLS1_1\fP,
and \fBTLS1_2\fP\&.
.INDENT 7.0
.IP \(bu 2
On macOS, you cannot disable \fBTLS1_1\fP and leave both \fBTLS1_0\fP and
\fBTLS1_2\fP enabled. You must disable at least one of the other
two, for example, \fBTLS1_0,TLS1_1\fP\&.
.IP \(bu 2
To list multiple protocols, specify as a comma separated list of
protocols. For example \fBTLS1_0,TLS1_1\fP\&.
.IP \(bu 2
Specifying an unrecognized protocol will prevent the server from
starting.
.IP \(bu 2
The specified disabled protocols overrides any default disabled
protocols.
.UNINDENT
.sp
Starting in version 4.0, MongoDB disables the use of TLS 1.0 if TLS
1.1+ is available on the system. To enable the disabled TLS 1.0,
specify \fBnone\fP to \fI\%\-\-sslDisabledProtocols\fP\&. 4.0\-disable\-tls
.sp
Members of replica sets and sharded clusters must speak at least one
protocol in common.
.sp
\fBSEE ALSO:\fP
.INDENT 7.0
.INDENT 3.5
ssl\-disallow\-protocols
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-sslFIPSMode
Directs the \fBmongod\fP to use the FIPS mode of the installed OpenSSL
library. Your system must have a FIPS
compliant OpenSSL library to use the \fI\%\-\-sslFIPSMode\fP option.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
FIPS\-compatible TLS/SSL is
available only in \fI\%MongoDB Enterprise\fP\&. See
/tutorial/configure\-fips for more information.
.UNINDENT
.UNINDENT
.UNINDENT
.SS Profiler Options
.INDENT 0.0
.TP
.B \-\-profile <level>
\fIDefault\fP: 0
.sp
Configures the database profiler level.
The following profiler levels are available:
.TS
center;
|l|l|.
_
T{
Level
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
The profiler is off and does not collect any data.
This is the default profiler level.
T}
_
T{
\fB1\fP
T}	T{
The profiler collects data for operations that take longer
than the value of \fBslowms\fP\&.
T}
_
T{
\fB2\fP
T}	T{
The profiler collects data for all operations.
T}
_
.TE
.sp
\fBIMPORTANT:\fP
.INDENT 7.0
.INDENT 3.5
Profiling can impact performance and shares settings with the system
log. Carefully consider any performance and security implications
before configuring and enabling the profiler on a production
deployment.
.sp
See database\-profiling\-overhead for more information on
potential performance degradation.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-slowms <integer>
\fIDefault\fP: 100
.sp
The \fIslow\fP operation time threshold, in milliseconds. Operations
that run for longer than this threshold are considered \fIslow\fP\&.
.sp
When \fBlogLevel\fP is set to \fB0\fP, MongoDB
records \fIslow\fP operations to the diagnostic log at a rate determined by
\fBslowOpSampleRate\fP\&. At higher
\fBlogLevel\fP settings, all operations appear in the diagnostic
log regardless of their latency.
.sp
For \fI\%mongod\fP instances, \fI\%\-\-slowms\fP affects the diagnostic log
and, if enabled, the profiler.
.sp
\fBSEE ALSO:\fP
.INDENT 7.0
.INDENT 3.5
/tutorial/manage\-the\-database\-profiler
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-slowOpSampleRate <double>
\fIDefault\fP: 1.0
.sp
The fraction of \fIslow\fP operations that should be profiled or logged.
\fI\%\-\-slowOpSampleRate\fP accepts values between 0 and 1, inclusive.
.sp
For \fI\%mongod\fP instances, \fI\%\-\-slowOpSampleRate\fP affects the
diagnostic log and, if enabled, the profiler.
.UNINDENT
.SS Audit Options
.INDENT 0.0
.TP
.B \-\-auditDestination
Enables auditing and specifies where
\fBmongod\fP sends all audit events.
.sp
\fI\%\-\-auditDestination\fP can have one of the following values:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBsyslog\fP
T}	T{
Output the audit events to syslog in JSON format. Not available on
Windows. Audit messages have a syslog severity level of \fBinfo\fP
and a facility level of \fBuser\fP\&.
.sp
The syslog message limit can result in the truncation of
audit messages. The auditing system will neither detect the
truncation nor error upon its occurrence.
T}
_
T{
\fBconsole\fP
T}	T{
Output the audit events to \fBstdout\fP in JSON format.
T}
_
T{
\fBfile\fP
T}	T{
Output the audit events to the file specified in
\fI\%\-\-auditPath\fP in the format specified in
\fI\%\-\-auditFormat\fP\&.
T}
_
.TE
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
Available only in \fI\%MongoDB Enterprise\fP\&.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-auditFormat
New in version 2.6.

.sp
Specifies the format of the output file for auditing if \fI\%\-\-auditDestination\fP is \fBfile\fP\&. The
\fI\%\-\-auditFormat\fP option can have one of the following values:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBJSON\fP
T}	T{
Output the audit events in JSON format to the file specified
in \fI\%\-\-auditPath\fP\&.
T}
_
T{
\fBBSON\fP
T}	T{
Output the audit events in BSON binary format to the file
specified in \fI\%\-\-auditPath\fP\&.
T}
_
.TE
.sp
Printing audit events to a file in JSON format degrades server
performance more than printing to a file in BSON format.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
Available only in \fI\%MongoDB Enterprise\fP\&.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-auditPath
New in version 2.6.

.sp
Specifies the output file for auditing if
\fI\%\-\-auditDestination\fP has value of \fBfile\fP\&. The \fI\%\-\-auditPath\fP
option can take either a full path name or a relative path name.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
Available only in \fI\%MongoDB Enterprise\fP\&.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-auditFilter
New in version 2.6.

.sp
Specifies the filter to limit the types of operations the audit system records. The option takes a string representation
of a query document of the form:
.INDENT 7.0
.INDENT 3.5
.sp
.nf
.ft C
{ <field1>: <expression1>, ... }
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
The \fB<field>\fP can be any field in the audit message, including fields returned in the
param document. The
\fB<expression>\fP is a query condition expression\&.
.sp
To specify an audit filter, enclose the filter document in single
quotes to pass the document as a string.
.sp
To specify the audit filter in a configuration file, you must use the YAML format of
the configuration file.
.sp
\fBNOTE:\fP
.INDENT 7.0
.INDENT 3.5
Available only in \fI\%MongoDB Enterprise\fP\&.
.UNINDENT
.UNINDENT
.UNINDENT
.SS SNMP Options
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
MongoDB Enterprise on macOS does \fInot\fP include support for SNMP due
to \fI\%SERVER\-29352\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-snmp\-subagent
Runs SNMP as a subagent. For more information, see
/tutorial/monitor\-with\-snmp\&.
.UNINDENT
.INDENT 0.0
.TP
.B \-\-snmp\-master
Runs SNMP as a master. For more information, see
/tutorial/monitor\-with\-snmp\&.
.UNINDENT
.SS inMemory Options
.INDENT 0.0
.TP
.B \-\-inMemorySizeGB <float>
\fIDefault\fP: 50% of physical RAM less 1 GB
.sp
Changed in version 3.4: Values can range from 256MB to 10TB and can be a float.

.sp
Maximum amount of memory to allocate for in\-memory storage
engine data, including indexes, oplog if the
\fI\%mongod\fP is part of replica set, replica set or sharded
cluster metadata, etc.
.sp
By default, the in\-memory storage engine uses 50% of physical RAM minus
1 GB.
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.SS Encryption Key Management Options
.INDENT 0.0
.TP
.B \-\-enableEncryption <boolean>
\fIDefault\fP: False
.sp
New in version 3.2.

.sp
Enables encryption for the WiredTiger storage engine. You must set
to \fBtrue\fP to pass in encryption keys and configurations.
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-encryptionCipherMode <string>
\fIDefault\fP: AES256\-CBC
.sp
New in version 3.2.

.sp
The cipher mode to use for encryption at rest:
.TS
center;
|l|l|.
_
T{
Mode
T}	T{
Description
T}
_
T{
\fBAES256\-CBC\fP
T}	T{
256\-bit Advanced Encryption Standard in Cipher Block Chaining
Mode
T}
_
T{
\fBAES256\-GCM\fP
T}	T{
256\-bit Advanced Encryption Standard in Galois/Counter Mode
.sp
Available only on Linux.
.sp
Changed in version 4.0: MongoDB Enterprise on Windows no longer supports \fBAES256\-GCM\fP\&.
T}
_
.TE
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-encryptionKeyFile <string>
New in version 3.2.

.sp
The path to the local keyfile when managing keys via process \fIother
than\fP KMIP. Only set when managing keys via process other than KMIP.
If data is already encrypted using KMIP, MongoDB will throw an error.
.sp
Requires \fBenableEncryption\fP to be \fBtrue\fP\&.
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-kmipKeyIdentifier <string>
New in version 3.2.

.sp
Unique KMIP identifier for an existing key within the KMIP server.
Include to use the key associated with the identifier as the system
key. You can only use the setting the first time you enable
encryption for the \fI\%mongod\fP instance. Requires
\fBenableEncryption\fP to be true.
.sp
If unspecified, MongoDB will request that the KMIP server create a
new key to utilize as the system key.
.sp
If the KMIP server cannot locate a key with the specified identifier
or the data is already encrypted with a key, MongoDB will throw an
error
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-kmipRotateMasterKey <boolean>
\fIDefault\fP: False
.sp
New in version 3.2.

.sp
If true, rotate the master key and re\-encrypt the internal
keystore.
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.sp
\fBSEE ALSO:\fP
.INDENT 7.0
.INDENT 3.5
kmip\-master\-key\-rotation
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-kmipServerName <string>
New in version 3.2.

.sp
Hostname or IP address of key management solution running a KMIP
server. Requires \fBenableEncryption\fP to be true.
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-kmipPort <number>
\fIDefault\fP: 5696
.sp
New in version 3.2.

.sp
Port number the KMIP server is listening on. Requires that a
\fBkmipServerName\fP be provided. Requires
\fBenableEncryption\fP to be true.
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-kmipClientCertificateFile <string>
New in version 3.2.

.sp
String containing the path to the client certificate used for
authenticating MongoDB to the KMIP server. Requires that a
\fBkmipServerName\fP be provided.
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-kmipClientCertificatePassword <string>
New in version 3.2.

.sp
The password (if one exists) for the client certificate passed into
\fBkmipClientCertificateFile\fP\&. Is used for
authenticating MongoDB to the KMIP server. Requires that a
\fBkmipClientCertificateFile\fP be provided.
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B \-\-kmipServerCAFile <string>
New in version 3.2.

.sp
Path to CA File. Used for validating secure client connection to
KMIP server.
.UNINDENT
.SS Text Search Options
.INDENT 0.0
.TP
.B \-\-basisTechRootDirectory <path>
New in version 3.2.

.sp
Specify the root directory of the Basis Technology Rosette
Linguistics Platform installation to support additional languages for
text search operations.
.INDENT 7.0
.INDENT 3.5
.IP "Enterprise Feature"
.sp
Available in MongoDB Enterprise only.
.UNINDENT
.UNINDENT
.UNINDENT
.SH AUTHOR
MongoDB Documentation Project
.SH COPYRIGHT
2008-2018
.\" Generated by docutils manpage writer.
.