mongodb3.2 replica sets

一、配置文件 /etc/mongod.conf

[root@mongo01 ~]# egrep -v "^(#|$)" /etc/mongod.confsystemLog:  destination: file  logAppend: true  path: /data/mongodb/log/rs1.logstorage:  dbPath: /data/mongodb/data  directoryPerDB: true  journal:    enabled: trueprocessManagement:  fork: true  # fork and run in background  pidFilePath: /data/mongodb/conf/mongod.pid  # location of pidfilenet:  port: 27027replication:   oplogSizeMB: 50000   replSetName: rs1[root@mongo01 ~]#[root@mongo01 ~]# ls /data/mongodb/arbiter  conf  data  log  startaribiter.sh[root@mongo01 ~]# ls /data/mongodb/arbiter/arbiter.conf  conf  data  log[root@mongo01 ~]# egrep -v "^(#|$)" /data/mongodb/arbiter/arbiter.confsystemLog:  destination: file  logAppend: true  path: /data/mongodb/arbiter/log/rs1.logstorage:  dbPath: /data/mongodb/arbiter/data  directoryPerDB: true  journal:    enabled: trueprocessManagement:  fork: true  # fork and run in background  pidFilePath: /data/mongodb/arbiter/conf/mongod.pid  # location of pidfilenet:  port: 27029replication:   oplogSizeMB: 50000   replSetName: rs1[root@mongo01 ~]# cat /data/mongodb/startarbiter.sh#!/bin/sh. /etc/rc.d/init.d/functionscd ${0%/*}/arbiterdaemon --user mongod "mongod --config arbiter.conf"[root@mongo01 ~]#

注意：arbiter.conf文件的属主、属组为mongod

二、启动服务，配置副本集

service mongod  start /data/mongodb/startaribiter.sh

启动第二个节点，然后在primary上操作如下：

rs.initiate()rs.add("mongodb2.example.net")rs.add("mongodb3.example.net")rs.addArb("mongodb1.example.net:27029")

如果希望降低primary的优先级：

cfg = rs.conf()cfg.members[2].priority = 0.5rs.reconfig(cfg)rs.status()

实现复制后，在从节点上查看数据如下：

SECONDARY> rs.slaveOk()SECONDARY> show collections

三、 使用keyFile实现复制验证

在主节点上创建群集用户及密码如下：

admin = db.getSiblingDB("admin")admin.createUser(  {    user: "clusteradmin",    pwd: "clusterpwd",    roles: [     { role: "userAdminAnyDatabase", db: "admin" },    { role: "clusterAdmin", db: "admin" },    { role: "root", db: "admin" }    ]  })

测试用户：

db.getSiblingDB("admin").auth("clusteradmin", "clusterpwd" )

在各从节点上关闭服务：

use admin

db.shutdownServer()

包括arbiter节点也要关闭服务，最后再关闭primary节点的服务。

在各配置文件mongod.conf文件中添加auth相关的文件，配置如下所示：

security:  keyFile: /data/mongodb/conf/keyfile.key[root@mongo01 ~]# cat /data/mongodb/conf/keyfile.keyabcdefgh该文件的权限必须是600或400，并把该文件复制到各节点上（保持内容相同），该文件也可以使用以下命令生成：openssl rand -base64 755 >  path-to-keyfile

最后再新启动各节点的mongodb服务，并重新login ，测试。

参考：

https://docs.mongodb.com/manual/tutorial/deploy-replica-set/

https://docs.mongodb.com/manual/tutorial/enforce-keyfile-access-control-in-existing-replica-set/

四、补充 CentOS7上部署mongodb 3.6的 RS

(1) 在vm2主机上配置mongod如下所示：

[root@vm2 ~]# mkdir -p /data/mongodb/{conf,run,logs,data}[root@vm2 ~]# chown -R mongod.mongod /data/mongodb[root@vm2 ~]# vim /etc/mongod.conf[root@vm2 ~]# grep -Pv "^(#|$)" /etc/mongod.conf systemLog:  destination: file  logAppend: true  path: /data/mongodb/logs/mongod.logstorage:  dbPath: /data/mongodb/data/  directoryPerDB: true  journal:    enabled: trueprocessManagement:  fork: true  # fork and run in background  pidFilePath: /data/mongodb/run/mongod.pid  # location of pidfile  timeZoneInfo: /usr/share/zoneinfonet:  port: 27027  bindIp: 0.0.0.0  # Listen to local interface only, comment to listen on all interfaces.security:  authorization: enabled  keyFile: /data/mongodb/conf/keyFilereplication:  replSetName: rs0[root@vm2 ~]# 注：必须保证 mongod.conf文件与mongod.service文件中的各路径设置一致，否则会导致启动失败[root@vm2 ~]# cd /usr/lib/systemd/system/[root@vm2 system]# head -15 mongod.service [Unit]Description=High-performance, schema-free document-oriented databaseAfter=network.targetDocumentation=https://docs.mongodb.org/manual[Service]User=mongodGroup=mongodEnvironment="OPTIONS=-f /etc/mongod.conf"ExecStart=/usr/bin/mongod $OPTIONSExecStartPre=/usr/bin/mkdir -p /data/mongodb/runExecStartPre=/usr/bin/chown mongod:mongod /data/mongodb/runExecStartPre=/usr/bin/chmod 0755 /data/mongodb/runPermissionsStartOnly=truePIDFile=/data/mongodb/run/mongod.pid[root@vm2 system]#[root@vm2 ~]# openssl rand -base64 755 >  /data/mongodb/conf/keyFile[root@vm2 ~]# chown mongod.mongod /data/mongodb/conf/keyFile[root@vm2 ~]# chmod 400 /data/mongodb/conf/keyFile

（2）在vm2主机上配置arbiter 如下所示：

[root@vm2 data]# mkdir arbiter/{conf,data,logs,run} -p[root@vm2 data]# cp mongodb/conf/keyFile  arbiter/conf/[root@vm2 data]# chmod 400 /data/arbiter/conf/[root@vm2 data]# cp /etc/mongod.conf arbiter/conf/[root@vm2 data]# mv conf/mongod.conf conf/arbiter.conf[root@vm2 data]# vim arbiter/conf/arbiter.conf[root@vm2 data]# chown -R mongod.mongod  arbiter[root@vm2 data]# grep -Pv "^(#|$)" arbiter/conf/arbiter.conf systemLog:  destination: file  logAppend: true  path: /data/arbiter/logs/arbiter.logstorage:  dbPath: /data/arbiter/data/  directoryPerDB: true  journal:    enabled: trueprocessManagement:  fork: true  # fork and run in background  pidFilePath: /data/arbiter/run/arbiter.pid  # location of pidfile  timeZoneInfo: /usr/share/zoneinfonet:  port: 37027  bindIp: 0.0.0.0  # Listen to local interface only, comment to listen on all interfaces.security:  authorization: enabled  keyFile: /data/arbiter/conf/keyFilereplication:  replSetName: rs0[root@vm2 data]#[root@vm2 data]# cd /usr/lib/systemd/system[root@vm2 system]# cp mongod.service arbiter.service[root@vm2 system]# vim arbiter.service [root@vm2 system]# head -15 arbiter.service[Unit]Description=High-performance, schema-free document-oriented databaseAfter=network.targetDocumentation=https://docs.mongodb.org/manual[Service]User=mongodGroup=mongodEnvironment="OPTIONS=-f /data/arbiter/conf/arbiter.conf"ExecStart=/usr/bin/mongod $OPTIONSExecStartPre=/usr/bin/mkdir -p /data/arbiter/runExecStartPre=/usr/bin/chown mongod:mongod /data/arbiter/runExecStartPre=/usr/bin/chmod 0755 /data/arbiter/runPermissionsStartOnly=truePIDFile=/data/arbiter/run/arbiter.pid[root@vm2 system]# [root@vm2 system]# systemctl daemon-reload[root@vm2 arbiter]# tree .├── conf│   ├── arbiter.conf│   └── keyFile├── data├── logs└── run4 directories, 2 files[root@vm2 arbiter]#[root@vm2 data]# echo never > /sys/kernel/mm/transparent_hugepage/enabled[root@vm2 data]# systemctl restart mongod[root@vm2 data]# systemctl restart arbiter[root@vm2 data]# ps -ef | grep mongodmongod   130256      1  8 12:46 ?        00:00:01 /usr/bin/mongod -f /etc/mongod.confmongod   130354      1 14 12:46 ?        00:00:01 /usr/bin/mongod -f /data/arbiter/conf/arbiter.confroot     130387 125564  0 12:46 pts/0    00:00:00 grep --color=auto mongod[root@vm2 data]#

（3）在另一台mongodb server上安装并配置mongodb，配置内容与vm2上完全相同。然后添加rs，操作如下：

[root@meteor ~]# cat /sys/kernel/mm/transparent_hugepage/enabled[always] madvise never[root@meteor ~]# echo never > /sys/kernel/mm/transparent_hugepage/enabled[root@meteor ~]# systemctl restart mongod[root@meteor ~]# mongo localhost:27027/admin -uroot -pMongoDB shell version v3.6.5Enter password: connecting to: mongodb://localhost:27027/adminMongoDB server version: 3.6.5> show dbs2018-05-26T20:41:42.392+0800 E QUERY    [thread1] Error: listDatabases failed:{    "ok" : 0,    "errmsg" : "not master and slaveOk=false",    "code" : 13435,    "codeName" : "NotMasterNoSlaveOk"} :_getErrorWithCode@src/mongo/shell/utils.js:25:13Mongo.prototype.getDBs@src/mongo/shell/mongo.js:65:1shellHelper.show@src/mongo/shell/utils.js:849:19shellHelper@src/mongo/shell/utils.js:739:15@(shellhelp2):1:1> rs.slaveOk()> rs.status(){    "info" : "run rs.initiate(...) if not yet done for the set",    "ok" : 0,    "errmsg" : "no replset config has been received",    "code" : 94,    "codeName" : "NotYetInitialized"}> config={"_id":"rs0","members":[... {"_id":0,"host":"192.168.20.221:27027","priority":100},... {"_id":1,"host":"192.168.40.206:27027","priority":1},... {"_id":2,"host":"192.168.40.206:37027","priority":0,"arbiterOnly":true}... ] }{    "_id" : "rs0",    "members" : [        {            "_id" : 0,            "host" : "192.168.20.221:27027",            "priority" : 100        },        {            "_id" : 1,            "host" : "192.168.40.206:27027",            "priority" : 1        },        {            "_id" : 2,            "host" : "192.168.40.206:37027",            "priority" : 0,            "arbiterOnly" : true        }    ]}> rs.initiate(config){ "ok" : 1 }rs0:SECONDARY> rs0:SECONDARY> rs0:PRIMARY> rs0:PRIMARY> rs.status(){    "set" : "rs0",    "date" : ISODate("2018-05-26T12:49:29.987Z"),    "myState" : 1,    "term" : NumberLong(1),    "heartbeatIntervalMillis" : NumberLong(2000),    "optimes" : {        "lastCommittedOpTime" : {            "ts" : Timestamp(1527338963, 1),            "t" : NumberLong(1)        },        "readConcernMajorityOpTime" : {            "ts" : Timestamp(1527338963, 1),            "t" : NumberLong(1)        },        "appliedOpTime" : {            "ts" : Timestamp(1527338963, 1),            "t" : NumberLong(1)        },        "durableOpTime" : {            "ts" : Timestamp(1527338963, 1),            "t" : NumberLong(1)        }    },    "members" : [        {            "_id" : 0,            "name" : "192.168.20.221:27027",            "health" : 1,            "state" : 1,            "stateStr" : "PRIMARY",            "uptime" : 503,            "optime" : {                "ts" : Timestamp(1527338963, 1),                "t" : NumberLong(1)            },            "optimeDate" : ISODate("2018-05-26T12:49:23Z"),            "infoMessage" : "could not find member to sync from",            "electionTime" : Timestamp(1527338942, 1),            "electionDate" : ISODate("2018-05-26T12:49:02Z"),            "configVersion" : 1,            "self" : true        },        {            "_id" : 1,            "name" : "192.168.40.206:27027",            "health" : 1,            "state" : 2,            "stateStr" : "SECONDARY",            "uptime" : 38,            "optime" : {                "ts" : Timestamp(1527338963, 1),                "t" : NumberLong(1)            },            "optimeDurable" : {                "ts" : Timestamp(1527338963, 1),                "t" : NumberLong(1)            },            "optimeDate" : ISODate("2018-05-26T12:49:23Z"),            "optimeDurableDate" : ISODate("2018-05-26T12:49:23Z"),            "lastHeartbeat" : ISODate("2018-05-26T12:49:28.268Z"),            "lastHeartbeatRecv" : ISODate("2018-05-26T12:49:28.274Z"),            "pingMs" : NumberLong(1),            "syncingTo" : "192.168.20.221:27027",            "configVersion" : 1        },        {            "_id" : 2,            "name" : "192.168.40.206:37027",            "health" : 1,            "state" : 7,            "stateStr" : "ARBITER",            "uptime" : 38,            "lastHeartbeat" : ISODate("2018-05-26T12:49:28.266Z"),            "lastHeartbeatRecv" : ISODate("2018-05-26T12:49:29.107Z"),            "pingMs" : NumberLong(1),            "configVersion" : 1        }    ],    "ok" : 1,    "operationTime" : Timestamp(1527338963, 1),    "$clusterTime" : {        "clusterTime" : Timestamp(1527338963, 1),        "signature" : {            "hash" : BinData(0,"xxW1WBNE99FOs8BNdAanWKOhFUk="),            "keyId" : NumberLong("6559870810092208129")        }    }}rs0:PRIMARY>

（4）在secondary节点上登录，并查看状态，验证数据一致性。

说明：

priority：表示一个成员被选举为Primary节点的优先级，默认值是1，取值范围是从0到100，将priority设置为0有特殊含义：Priority为0的成员永远不能成为Primary 节点。Replica Set中，Priority最高的成员，会优先被选举为Primary 节点，只要其满足条件。
hidden：将成员配置为隐藏成员，要求Priority 为0。Client不会向隐藏成员发送请求，因此隐藏成员不会收到Client的Request。
slaveDelay：单位是秒，将Secondary 成员配置为延迟备份节点，要求Priority 为0，表示该成员比Primary 成员滞后指定的时间，才能将Primary上进行的写操作同步到本地。为了数据读取的一致性，应将延迟备份节点的hidden设置为true，避免用户读取到明显滞后的数据。Delayed members maintain a copy of the data that reflects the state of the data at some time in the past.
votes：有效值是0或1，默认值是1，如果votes是1，表示该成员（voting member）有权限选举Primary 成员。在一个Replica Set中，最多有7个成员，其votes 属性的值是1。
arbiterOnly：表示该成员是仲裁者，arbiter的唯一作用是就是参与选举，其votes属性是1，arbiter不保存数据，也不会为client提供服务。

总结：本内容前半部分是使用rs.add("....")的方法添加副本集，而后半部分是使用 先定义config ，然后再 rs.initiate(config)的方法 添加副本集。各位朋友可根据需要各自选用不同的方法