介绍安装 MongoDB副本集搭建及基础使用命令
安装 MongoDB 4.2
参考: https://docs.mongodb.com/manual/tutorial/install-mongodb-on-ubuntu/#
- 官方安装
wget -qO - https://www.mongodb.org/static/pgp/server-4.2.asc | sudo apt-key add -
sudo apt-get install gnupg
echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.2 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.2.list # 1804
# echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu xenial/mongodb-org/4.2 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.2.list # 1604
sudo apt-get update
sudo apt-get install -y mongodb-org
- 国内源
https://mirrors.tuna.tsinghua.edu.cn/help/mongodb/
重启命令
sudo systemctl start mongod
sudo systemctl status mongod
sudo systemctl enable mongod #开机启动
usage
mongo
卸载
sudo apt-get purge mongodb-org*
sudo rm -r /var/log/mongodb
sudo rm -r /var/lib/mongodb
集群简介
mongodb集群搭建有三种方式。
- Master-Slave模式
- Replica-Set方式
- Sharding方式
官方推荐副本集和分片的方式, 下面使用副本集方式搭建 mongodb 集群.
部署集群
-
在单台 PC 上 操作
-
3 个 mongo服务 开启端口分别:27010, 27011, 27012:
-
hostname 为 n1, 可以改成对应的 ip
部署复制集
path=/home/chenwei
mkdir master slaver arbiter
cat <<EOF >>master.conf
dbpath=/home/chenwei/master
logpath=/home/chenwei/master.log
pidfilepath=/home/chenwei/master.pid
directoryperdb=true
logappend=true
replSet=HPC
bind_ip=0.0.0.0
port=27010
oplogSize=10000
fork=true
EOF
cat <<EOF >>slaver.conf
dbpath=/home/chenwei/slaver
logpath=/home/chenwei/slaver.log
pidfilepath=/home/chenwei/slaver.pid
directoryperdb=true
logappend=true
replSet=HPC
bind_ip=0.0.0.0
port=27011
oplogSize=10000
fork=true
EOF
cat <<EOF >>arbiter.conf
dbpath=/home/chenwei/arbiter
logpath=/home/chenwei/arbiter.log
pidfilepath=/home/chenwei/arbiter.pid
directoryperdb=true
logappend=true
replSet=HPC
bind_ip=0.0.0.0
port=27012
oplogSize=10000
fork=true
EOF
mongod -f master.conf
mongod -f slaver.conf
mongod -f arbiter.conf
初始化复制集：
mongo -p 27010
use admin
rs.initiate( {
_id : "HPC",
members: [
{ _id: 0, host: "n1:27010" },
{ _id: 1, host: "n1:27011"},
{ _id: 2, host: "n1:27012" }
]
})
查看配置情况
rs.conf()
rs.status()
显示如下
{
"set" : "HPC",
"date" : ISODate("2020-03-03T08:04:54.714Z"),
"myState" : 1,
"term" : NumberLong(1),
"syncingTo" : "",
"syncSourceHost" : "",
"syncSourceId" : -1,
"heartbeatIntervalMillis" : NumberLong(2000),
"majorityVoteCount" : 2,
"writeMajorityCount" : 2,
"optimes" : {
"lastCommittedOpTime" : {
"ts" : Timestamp(0, 0),
"t" : NumberLong(-1)
},
"lastCommittedWallTime" : ISODate("1970-01-01T00:00:00Z"),
"appliedOpTime" : {
"ts" : Timestamp(1583222693, 5),
"t" : NumberLong(1)
},
"durableOpTime" : {
"ts" : Timestamp(1583222693, 5),
"t" : NumberLong(1)
},
"lastAppliedWallTime" : ISODate("2020-03-03T08:04:53.892Z"),
"lastDurableWallTime" : ISODate("2020-03-03T08:04:53.892Z")
},
"lastStableRecoveryTimestamp" : Timestamp(0, 0),
"lastStableCheckpointTimestamp" : Timestamp(0, 0),
"electionCandidateMetrics" : {
"lastElectionReason" : "electionTimeout",
"lastElectionDate" : ISODate("2020-03-03T08:04:53.108Z"),
"electionTerm" : NumberLong(1),
"lastCommittedOpTimeAtElection" : {
"ts" : Timestamp(0, 0),
"t" : NumberLong(-1)
},
"lastSeenOpTimeAtElection" : {
"ts" : Timestamp(1583222682, 1),
"t" : NumberLong(-1)
},
"numVotesNeeded" : 2,
"priorityAtElection" : 1,
"electionTimeoutMillis" : NumberLong(10000),
"numCatchUpOps" : NumberLong(0),
"newTermStartDate" : ISODate("2020-03-03T08:04:53.834Z")
},
"members" : [
{
"_id" : 0,
"name" : "n1:27010",
"health" : 1,
"state" : 1,
"stateStr" : "PRIMARY",
"uptime" : 267,
"optime" : {
"ts" : Timestamp(1583222693, 5),
"t" : NumberLong(1)
},
"optimeDate" : ISODate("2020-03-03T08:04:53Z"),
"syncingTo" : "",
"syncSourceHost" : "",
"syncSourceId" : -1,
"infoMessage" : "could not find member to sync from",
"electionTime" : Timestamp(1583222693, 1),
"electionDate" : ISODate("2020-03-03T08:04:53Z"),
"configVersion" : 1,
"self" : true,
"lastHeartbeatMessage" : ""
},
{
"_id" : 1,
"name" : "n1:27011",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 12,
"optime" : {
"ts" : Timestamp(1583222682, 1),
"t" : NumberLong(-1)
},
"optimeDurable" : {
"ts" : Timestamp(1583222682, 1),
"t" : NumberLong(-1)
},
"optimeDate" : ISODate("2020-03-03T08:04:42Z"),
"optimeDurableDate" : ISODate("2020-03-03T08:04:42Z"),
"lastHeartbeat" : ISODate("2020-03-03T08:04:53.122Z"),
"lastHeartbeatRecv" : ISODate("2020-03-03T08:04:54.237Z"),
"pingMs" : NumberLong(0),
"lastHeartbeatMessage" : "",
"syncingTo" : "",
"syncSourceHost" : "",
"syncSourceId" : -1,
"infoMessage" : "",
"configVersion" : 1
},
{
"_id" : 2,
"name" : "n1:27012",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 12,
"optime" : {
"ts" : Timestamp(1583222682, 1),
"t" : NumberLong(-1)
},
"optimeDurable" : {
"ts" : Timestamp(1583222682, 1),
"t" : NumberLong(-1)
},
"optimeDate" : ISODate("2020-03-03T08:04:42Z"),
"optimeDurableDate" : ISODate("2020-03-03T08:04:42Z"),
"lastHeartbeat" : ISODate("2020-03-03T08:04:53.124Z"),
"lastHeartbeatRecv" : ISODate("2020-03-03T08:04:54.319Z"),
"pingMs" : NumberLong(0),
"lastHeartbeatMessage" : "",
"syncingTo" : "",
"syncSourceHost" : "",
"syncSourceId" : -1,
"infoMessage" : "",
"configVersion" : 1
}
],
"ok" : 1,
"$clusterTime" : {
"clusterTime" : Timestamp(1583222693, 5),
"signature" : {
"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
"keyId" : NumberLong(0)
}
},
"operationTime" : Timestamp(1583222693, 5)
}
1台为PRIMARY，其他2台为SECONDARY。
分片复制集
TODO
基本命令用法
创建数据库
use demo
#如果数据库不存在，则创建数据库，否则切换到指定数据库。
db.dropDatabase()
# 删除
show dbs
# 查看数据库
增删改查
db.demo.insert({"name":"test"})
db.demo.insert({'title':'MongoDB 教程'})
db.demo.find()
db.demo.remove({'title':'MongoDB 教程'})
db.demo.find()
db.demo.update({'name':'test'},{$set:{'title':'MongoDB test'}})
集合
db.createCollection("co_users")
db.co_users.insert({"name" : "cw"})
db.co_users.find()
show collections
db.createCollection("mycol", { capped : true, autoIndexId : true, size : 6142800, max : 10000 } )
# 创建固定集合 mycol，整个集合空间大小 6142800 KB, 文档最大个数为 10000 个。
db.mycol.drop()
报错解决
not master and slaveOk=false
因为SECONDARY是不允许读写的， 在写多读少的应用中，使用Replica Sets来实现读写分离。通过在连接时指定或者在主库指定slaveOk，由Secondary来分担读的压力，Primary只承担写操作。 对于replica set 中的secondary 节点默认是不可读的，
- 解决方法:
在主库上设置 slaveok=ok
db.getMongo().setSlaveOk();