mongo/jstests/replsets/remove1.js

/* test removing a node from a replica set
 *
 * Start set with three nodes
 * Initial sync
 * Remove slave1
 * Remove slave2
 * Bring slave1 back up
 * Bring slave2 back up
 * Add them back as slave
 * Make sure everyone's secondary
 */

load("jstests/replsets/rslib.js");
var name = "removeNodes";
var host = getHostName();


print("Start set with three nodes");
var replTest = new ReplSetTest( {name: name, nodes: 2} );
var nodes = replTest.startSet();
replTest.initiate();
var master = replTest.getMaster();


print("Initial sync");
master.getDB("foo").bar.baz.insert({x:1});

replTest.awaitReplication();


print("Remove slaves");
var config = replTest.getReplSetConfig();

config.members.pop();
config.version = 2;
assert.soon(function() {
        try {
            master.getDB("admin").runCommand({replSetReconfig:config});
        }
        catch(e) {
            print(e);
        }

        reconnect(master);
        reconnect(replTest.nodes[1]);
        var c = master.getDB("local").system.replset.findOne();
        return c.version == 2;
    });

print("Add it back as a slave");
config.members.push({_id:1, host : host+":"+replTest.getPort(1)});
config.version = 3;
printjson(config);
wait(function() {
    try {
        master.getDB("admin").runCommand({replSetReconfig:config});
    }
    catch(e) {
        print(e);
    }
    reconnect(master);

    printjson(master.getDB("admin").runCommand({replSetGetStatus:1}));
    master.setSlaveOk();
    var newConfig = master.getDB("local").system.replset.findOne();
    print( "newConfig: " + tojson(newConfig) );
    return newConfig.version == 3;
} , "wait1" );


print("Make sure everyone's secondary");
wait(function() {
    var status = master.getDB("admin").runCommand({replSetGetStatus:1});
    occasionally(function() {
        printjson(status);
      });

    if (!status.members || status.members.length != 2) {
      return false;
    }

    for (var i = 0; i<2; i++) {
      if (status.members[i].state != 1 && status.members[i].state != 2) {
        return false;
      }
    }
    return true;
} , "wait2" );


print("reconfig with minority");
replTest.stop(1);

assert.soon(function() {
    try {
        return master.getDB("admin").runCommand({isMaster : 1}).secondary;
    }
    catch(e) {
        print("trying to get master: "+e);
    }
});

config.version = 4;
config.members.pop();
try {
    master.getDB("admin").runCommand({replSetReconfig : config, force : true});
}
catch(e) {
    print(e);
}

reconnect(master);
assert.soon(function() {
    return master.getDB("admin").runCommand({isMaster : 1}).ismaster;
});

config = master.getDB("local").system.replset.findOne();
printjson(config);
assert(config.version > 4);

replTest.stopSet();