说明
采用的mongo版版本： v4.4
mongo install
这里选择在debian10系统上，下载.tgz包安装
主要参考文档：https://www.mongodb.com/docs/v4.4/tutorial/install-mongodb-on-debian-tarball/
- 安装依赖包
sudo apt-get install libcurl4 openssl liblzma5
- 下载tgz包
curl -O https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-debian10-4.4.21.tgz
- 解压
mkdir /home/mongodb/
tar -xzf mongodb-linux-x86_64-debian10-4.4.21.tgz
mv mongodb-linux-x86_64-debian10-4.4.21 /home/mongodb/
- 启动mongodb测试
mkdir /home/mongodb/data
mkdir /home/mongodb/log
cd /home/mongodb/bin
./mongod --dbpath /home/mongodb/data --logpath /home/mongodb/log/mongod.log
开另外一个终端：
cd /home/mongodb/bin
# ./mongo --host 127.0.0.1 --port 27017
MongoDB shell version v4.4.21
connecting to: mongodb://127.0.0.1:27017/?compressors=disabled&gssapiServiceName=mongodb
Implicit session: session { "id" : UUID("80e17a43-dd43-4eb4-b7a0-7bf779a4d521") }
MongoDB server version: 4.4.21
---
..........
---
> show dbs
admin 0.000GB
config 0.000GB
local 0.000GB
>
mongo副本集
一个replica set(副本集)就是一组mongod的进程，提供冗余和高可用
replica set的成员，包括
- Primary
Primary接收所有的写请求 - Secondaries
Secondaries复制Primary的操作，维护一份相同的数据集
replica set推荐的最小配置是3个成员，1个primary，2个secondary，如果不像有2个secondary，可以把其中一个换成arbiter
成员，arbiter参与选举，但不存储数据
replica set最多可以有50个成员，但最多7个投票成员
通过—replSet选项启动replica set
用replica set名称：rs0, 搭建步骤如下
- 启动进程
mkdir /home/node1
mkdir /home/node2
mkdir /home/node3
./mongod --bind_ip 127.0.0.1 --port 27021 --dbpath "/home/node1" --replSet rs0 &
./mongod --bind_ip 127.0.0.1 --port 27022 --dbpath "/home/node2" --replSet rs0 &
./mongod --bind_ip 127.0.0.1 --port 27023 --dbpath "/home/node3" --replSet rs0 &
- 选择其中一个成员连上去，利用rs.initiate()初始化，这里选择node1:
./mongo --host 127.0.0.1 --port 27021
> rs.initiate()
{
"info2" : "no configuration specified. Using a default configuration for the set",
"me" : "127.0.0.1:27021",
"ok" : 1
}
查看配置
rs0:PRIMARY> rs.conf()
{
"_id" : "rs0",
"version" : 1,
"term" : 1,
"protocolVersion" : NumberLong(1),
"writeConcernMajorityJournalDefault" : true,
"members" : [
{
"_id" : 0,
"host" : "127.0.0.1:27021",
"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("6470116586009853042dae4d")
}
}
查看状态
rs0:PRIMARY> rs.status()
{
"set" : "rs0",
"date" : ISODate("2023-05-26T01:57:31.535Z"),
"myState" : 1,
"term" : NumberLong(1),
"syncSourceHost" : "",
"syncSourceId" : -1,
"heartbeatIntervalMillis" : NumberLong(2000),
"majorityVoteCount" : 1,
"writeMajorityCount" : 1,
"votingMembersCount" : 1,
"writableVotingMembersCount" : 1,
"optimes" : {
"lastCommittedOpTime" : {
"ts" : Timestamp(1685066245, 1),
"t" : NumberLong(1)
},
"lastCommittedWallTime" : ISODate("2023-05-26T01:57:25.606Z"),
"readConcernMajorityOpTime" : {
"ts" : Timestamp(1685066245, 1),
"t" : NumberLong(1)
},
"readConcernMajorityWallTime" : ISODate("2023-05-26T01:57:25.606Z"),
"appliedOpTime" : {
"ts" : Timestamp(1685066245, 1),
"t" : NumberLong(1)
},
"durableOpTime" : {
"ts" : Timestamp(1685066245, 1),
"t" : NumberLong(1)
},
"lastAppliedWallTime" : ISODate("2023-05-26T01:57:25.606Z"),
"lastDurableWallTime" : ISODate("2023-05-26T01:57:25.606Z")
},
"lastStableRecoveryTimestamp" : Timestamp(1685066205, 1),
"electionCandidateMetrics" : {
"lastElectionReason" : "electionTimeout",
"lastElectionDate" : ISODate("2023-05-26T01:54:45.421Z"),
"electionTerm" : NumberLong(1),
"lastCommittedOpTimeAtElection" : {
"ts" : Timestamp(0, 0),
"t" : NumberLong(-1)
},
"lastSeenOpTimeAtElection" : {
"ts" : Timestamp(1685066085, 1),
"t" : NumberLong(-1)
},
"numVotesNeeded" : 1,
"priorityAtElection" : 1,
"electionTimeoutMillis" : NumberLong(10000),
"newTermStartDate" : ISODate("2023-05-26T01:54:45.509Z"),
"wMajorityWriteAvailabilityDate" : ISODate("2023-05-26T01:54:45.562Z")
},
"members" : [
{
"_id" : 0,
"name" : "127.0.0.1:27021",
"health" : 1,
"state" : 1,
"stateStr" : "PRIMARY",
"uptime" : 212,
"optime" : {
"ts" : Timestamp(1685066245, 1),
"t" : NumberLong(1)
},
"optimeDate" : ISODate("2023-05-26T01:57:25Z"),
"lastAppliedWallTime" : ISODate("2023-05-26T01:57:25.606Z"),
"lastDurableWallTime" : ISODate("2023-05-26T01:57:25.606Z"),
"syncSourceHost" : "",
"syncSourceId" : -1,
"infoMessage" : "",
"electionTime" : Timestamp(1685066085, 2),
"electionDate" : ISODate("2023-05-26T01:54:45Z"),
"configVersion" : 1,
"configTerm" : 1,
"self" : true,
"lastHeartbeatMessage" : ""
}
],
"ok" : 1,
"$clusterTime" : {
"clusterTime" : Timestamp(1685066245, 1),
"signature" : {
"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
"keyId" : NumberLong(0)
}
},
"operationTime" : Timestamp(1685066245, 1)
}
- 把其他成员加入到replica set
必须连接到副本集primary主节点, 才能使用rs.add()添加剩余的成员
rs0:PRIMARY> rs.add("127.0.0.1:27022")
{
"ok" : 1,
"$clusterTime" : {
"clusterTime" : Timestamp(1685067569, 1),
"signature" : {
"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
"keyId" : NumberLong(0)
}
},
"operationTime" : Timestamp(1685067569, 1)
}
rs0:PRIMARY> rs.add("127.0.0.1:27023")
{
"ok" : 1,
"$clusterTime" : {
"clusterTime" : Timestamp(1685067609, 1),
"signature" : {
"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
"keyId" : NumberLong(0)
}
},
"operationTime" : Timestamp(1685067609, 1)
}
使用rs.status()查看副本集状态
删除replica set成员
rs0:PRIMARY> rs.remove("127.0.0.1:27022")
{
"ok" : 1,
"$clusterTime" : {
"clusterTime" : Timestamp(1685068022, 1),
"signature" : {
"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
"keyId" : NumberLong(0)
}
},
"operationTime" : Timestamp(1685068022, 1)
}
更多说明： https://www.mongodb.com/docs/v4.4/tutorial/remove-replica-set-member/
replica set成员状态
副本集的每个成员都有一个反映它在集合中的配置的状态。
| Number | Name | State Description |
|---|---|---|
| 0 | STARTUP | 还没有任何一个的活跃成员。所有成员在这个状态下都开始。副本集的符号解析配置文件在启动。 |
| 1 | PRIMARY | 主节点，唯一可以接受写操作的成员 |
| 2 | SECONDARY | 备份节点，复制数据存储的成员 |
| 3 | RECOVERING | 成员要么执行启动自我检查，或过渡完成回滚或重新同步。 |
| 5 | STARTUP2 | 该成员已加入该组，并运行一个初始同步。 |
| 6 | UNKNOWN | 成员的状态，是从其他集合的成员看，目前还不知道。 |
| 7 | ARBITER | 仲裁者不复制数据，只是为了参加选举。 |
| 8 | DOWN | 节点不可到达 |
| 9 | ROLLBACK | 该成员正在积极执行回滚。数据不可用于读取。 |
| 10 | REMOVED | 该成员曾经在一个副本集，但随后被删除。 |
在secondary中查看数据
rs0:SECONDARY> show dbs
uncaught exception: Error: listDatabases failed:{
"topologyVersion" : {
"processId" : ObjectId("6470172bd14082df2397456a"),
"counter" : NumberLong(7)
},
"operationTime" : Timestamp(1685068786, 1),
"ok" : 0,
"errmsg" : "not master and slaveOk=false",
"code" : 13435,
"codeName" : "NotPrimaryNoSecondaryOk",
"$clusterTime" : {
"clusterTime" : Timestamp(1685068786, 1),
"signature" : {
"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
"keyId" : NumberLong(0)
}
}
} :
_getErrorWithCode@src/mongo/shell/utils.js:25:13
Mongo.prototype.getDBs/<@src/mongo/shell/mongo.js:147:19
Mongo.prototype.getDBs@src/mongo/shell/mongo.js:99:12
shellHelper.show@src/mongo/shell/utils.js:937:13
shellHelper@src/mongo/shell/utils.js:819:15
@(shellhelp2):1:1
rs0:SECONDARY> rs.secondaryOk()
rs0:SECONDARY> show dbs
admin 0.000GB
config 0.000GB
local 0.000GB
rs.secondaryOk的作用： Allows read operations on secondary members for the MongoDB connection.
