通过.Net驱动程序配置Mongo副本集

Question

Is it possible using the .Net driver to:

• Check whether a certain Mongo instance is already a part of a replica
• Create a replica if not
• Add \\ Remove a node from an existing replica

Thanks!

Answer 1

Yes. But it's much easier to do these things in the mongo shell because it has helper functions defined already. Check out the replica set tutorials . For each step using some function in the mongo shell, for example rs.initiate() or rs.add() , you can see the code for the function by entering the function name with parentheses at the shell prompt:

> rs.initiate
function (c) { return db._adminCommand({ replSetInitiate: c }); }
> rs.add
function (hostport, arb) {
    var cfg = hostport;

    var local = db.getSisterDB("local");
    assert(local.system.replset.count() <= 1, "error: local.system.replset has unexpected contents");
    var c = local.system.replset.findOne();
    assert(c, "no config object retrievable from local.system.replset");

    c.version++;

    var max = 0;
    for (var i in c.members)
        if (c.members[i]._id > max) max = c.members[i]._id;
    if (isString(hostport)) {
        cfg = { _id: max + 1, host: hostport };
        if (arb)
            cfg.arbiterOnly = true;
    }
    if (cfg._id == null){
        cfg._id = max+1;
    }
    c.members.push(cfg);
    return this._runCmd({ replSetReconfig: c });
}

The code may be slightly different in your shell because of shell version; my shell is 3.0.1. You can use this code as a guide for writing your own versions of these functions in C#. You will use the RunCommand method to run the commands like replSetReconfig and replSetInitiate on the server(s).