mongo/jstests/replsets/stepdown.js

/**
 * Check that on a loss of primary, another node doesn't assume primary if it is stale. We force a
 * stepDown to test this.
 *
 * This test requires the fsync command to force a secondary to be stale.
 * @tags: [requires_fsync]
 */

load("jstests/replsets/rslib.js");

// utility to check if an error was due to connection failure.
var errorWasDueToConnectionFailure = function(error) {
    return error.message.indexOf("error doing query: failed") >= 0;
};

var replTest = new ReplSetTest({
    name : 'testSet',
    nodes : {
        "n0" : {
            rsConfig : {
                priority : 2
            }
        },
        "n1" : {},
        "n2" : {
            rsConfig : {
                votes : 1,
                priority : 0
            }
        }
    },
    nodeOptions : {
        verbose : 1
    }
});
var nodes = replTest.startSet();
replTest.initiate();
replTest.waitForState(nodes[0], ReplSetTest.State.PRIMARY, 60 * 1000);
var master = replTest.getPrimary();

// do a write
print("\ndo a write");
assert.writeOK(master.getDB("foo").bar.insert({x:1}));
replTest.awaitReplication();

// lock secondaries
print("\nlock secondaries");
replTest.liveNodes.slaves.forEach(function(slave) {
    printjson(assert.commandWorked(slave.getDB("admin").runCommand({fsync : 1, lock : 1})));
});

print("\nwaiting several seconds before stepdown");

sleep(2000);

for (var i = 0; i < 11; i++) {
    // do another write
    assert.writeOK(master.getDB("foo").bar.insert({x:i}));
    sleep(1000);
}

print("\n do stepdown that should not work");

// this should fail, so we don't need to try/catch
printjson(assert.commandFailed(master.getDB("admin").runCommand({replSetStepDown: 10})));

print("\n do stepdown that should work");
assert.throws(function() {
    assert.commandFailed(master.getDB("admin").runCommand({replSetStepDown:50, force:true}))
});

var r2 = assert.commandWorked(master.getDB("admin").runCommand({ismaster : 1}));
assert.eq(r2.ismaster, false);
assert.eq(r2.secondary, true);

print("\nunlock");
replTest.liveNodes.slaves.forEach(function(slave) {
    printjson(assert.commandWorked(slave.getDB("admin").fsyncUnlock()));
});

print("\nreset stepped down time");
assert.commandWorked(master.getDB("admin").runCommand({replSetFreeze:0}));
master = replTest.getPrimary();

print("\nawait");
replTest.awaitSecondaryNodes(90000);
replTest.awaitReplication();

// 'n0' may have just voted for 'n1', preventing it from becoming primary for the first 30 seconds
// of this assert.soon
assert.soon(function() {
    try {
        var result = master.getDB("admin").runCommand({isMaster: 1});
        return new RegExp(":" + replTest.nodes[0].port + "$").test(result.primary);
    } catch (x) {
        return false;
    }
}, "wait for n0 to be primary", 60000);

master = replTest.getPrimary();
var firstMaster = master;
print("\nmaster is now "+firstMaster);

try {
    assert.commandWorked(master.getDB("admin").runCommand({replSetStepDown : 100, force : true}));
}
catch (e) {
    // ignore errors due to connection failures as we expect the master to close connections
    // on stepdown
    if (!errorWasDueToConnectionFailure(e)) {
        throw e;
    }
}

print("\nget a master");
replTest.getPrimary();

assert.soon(function() {
    var secondMaster = replTest.getPrimary();
    return firstMaster.host !== secondMaster.host;
}, "making sure " + firstMaster.host + " isn't still master", 60000);

// Add arbiter for shutdown tests
replTest.add();
print("\ncheck shutdown command");

master = replTest.liveNodes.master;
var slave = replTest.liveNodes.slaves[0];

try {
    slave.adminCommand({shutdown :1});
}
catch (e) {
    print(e);
}


master = replTest.getPrimary();
assert.soon(function() {
    try {
        var result = master.getDB("admin").runCommand({replSetGetStatus:1});
        for (var i in result.members) {
            if (result.members[i].self) {
                continue;
            }

            return result.members[i].health == 0;
        }
    }
    catch (e) {
        print("error getting status from master: " + e);
        master = replTest.getPrimary();
        return false;
    }
}, 'make sure master knows that slave is down before proceeding');


print("\nrunning shutdown without force on master: "+master);

// this should fail because the master can't reach an up-to-date secondary (because the only 
// secondary is down)
var now = new Date();
assert.commandFailed(master.getDB("admin").runCommand({shutdown : 1, timeoutSecs : 3}));
// on windows, javascript and the server perceive time differently, to compensate here we use 2750ms
assert.gte((new Date()) - now, 2750);

print("\nsend shutdown command");

var currentMaster = replTest.getPrimary();
try {
    printjson(currentMaster.getDB("admin").runCommand({shutdown : 1, force : true}));
}
catch (e) {
    if (!errorWasDueToConnectionFailure(e)) {
        throw e;
    }
}

print("checking "+currentMaster+" is actually shutting down");
assert.soon(function() {
    try {
        currentMaster.findOne();
    }
    catch(e) {
        return true;
    }
    return false;
});

print("\nOK 1");

replTest.stopSet();

print("OK 2");