环境:
OS:Centos7
mongodb:4.4.22
我们在副本集扩容的情况下,新加入节点一般设置priority和votes都为0,待新节点数据同步完成后再进行修改:
主库上执行新增新的节点:
myrepl:PRIMARY>rs.add({ host: "192.168.1.107:29001", priority: 0, votes: 0 })
待同步完成后查看副本集配置
myrepl:PRIMARY> rs.config()
{
"_id" : "myrepl",
"version" : 23819,
"protocolVersion" : NumberLong(1),
"writeConcernMajorityJournalDefault" : true,
"members" : [
{
"_id" : 0,
"host" : "192.168.1.102:29001",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : 1,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
},
{
"_id" : 3,
"host" : "192.168.1.105:29001",
"arbiterOnly" : true,
"buildIndexes" : true,
"hidden" : false,
"priority" : 0,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
},
{
"_id" : 4,
"host" : "192.168.1.107:29001",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : 0,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 0
}
],
"settings" : {
"chainingAllowed" : true,
"heartbeatIntervalMillis" : 2000,
"heartbeatTimeoutSecs" : 10,
"electionTimeoutMillis" : 10000,
"catchUpTimeoutMillis" : -1,
"catchUpTakeoverDelayMillis" : 30000,
"getLastErrorModes" : {
},
"getLastErrorDefaults" : {
"w" : 1,
"wtimeout" : 0
},
"replicaSetId" : ObjectId("64b0a3f881b811c4931d4d4c")
}
}
可以看到id=4的节点,priority和votes都为0,下面进行修改
members的下标数字对对应数组的序号(这里是0,1,2),我们这里是要修改数组序号为2的member
myrepl:PRIMARY>var cfg = rs.conf()
myrepl:PRIMARY>cfg.members[2].priority = 1
myrepl:PRIMARY>cfg.members[2].votes = 1
myrepl:PRIMARY> rs.reconfig(cfg)
{
"ok" : 0,
"errmsg" : "Rejecting reconfig where the new config has a PSA topology and the secondary is electable, but the old config contains only one writable node. Refer to https://docs.mongodb.com/manual/reference/method/rs.reconfigForPSASet/ for next steps on reconfiguring a PSA set.",
"code" : 103,
"codeName" : "NewReplicaSetConfigurationIncompatible"
}
这里报错误了,提示说明psa拓扑不能使用这种方式修改,尝试使用如下方式修改
myrepl:PRIMARY>cfg = rs.conf();
myrepl:PRIMARY>cfg["members"] =
[
{
"_id" : 0,
"host" : "192.168.1.102:29001",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : 1,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
},
{
"_id" : 3,
"host" : "192.168.1.105:29001",
"arbiterOnly" : true,
"buildIndexes" : true,
"hidden" : false,
"priority" : 0,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
},
{
"_id" : 4,
"host" : "192.168.1.107:29001",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : 1,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
}
]
myrepl:PRIMARY> rs.reconfigForPSASet(2, cfg);
Running first reconfig to give member at index 2 { votes: 1, priority: 0 }
Running second reconfig to give member at index 2 { priority: 1 }
{ "ok" : 1 }
rs.reconfigForPSASet( memberIndex, config, { options } )的使用方法
memberIndex为member数组的序号
查看新配置
myrepl:PRIMARY> rs.conf()
{
"_id" : "myrepl",
"version" : 23821,
"protocolVersion" : NumberLong(1),
"writeConcernMajorityJournalDefault" : true,
"members" : [
{
"_id" : 0,
"host" : "192.168.1.102:29001",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : 1,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
},
{
"_id" : 3,
"host" : "192.168.1.105:29001",
"arbiterOnly" : true,
"buildIndexes" : true,
"hidden" : false,
"priority" : 0,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
},
{
"_id" : 4,
"host" : "192.168.1.107:29001",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : 1,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
}
],
"settings" : {
"chainingAllowed" : true,
"heartbeatIntervalMillis" : 2000,
"heartbeatTimeoutSecs" : 10,
"electionTimeoutMillis" : 10000,
"catchUpTimeoutMillis" : -1,
"catchUpTakeoverDelayMillis" : 30000,
"getLastErrorModes" : {
},
"getLastErrorDefaults" : {
"w" : 1,
"wtimeout" : 0
},
"replicaSetId" : ObjectId("64b0a3f881b811c4931d4d4c")
}
}