準備
EC2で3台構成で試す。
mongoのバージョンは3.2.9
Primary(db1), Secondary(db2), Arbiter(db3)の構成
wget http://downloads.mongodb.org/linux/mongodb-linux-x86_64-rhel62-3.2.9.tgz
confの設定とmongodの起動
内容は下記の通り
[root@db1 mongodb]# cat conf/rs01.conf
port = 27011
dbpath = /root/mongodb/data/rs01
fork = true
replSet = rs01
logpath = /root/mongodb/logs/mongors01.log
logappend = yes
smallfiles = true
storageEngine = wiredTiger
mongodプロセスを各サーバで起動する
./bin/mongod -f conf/rs01.conf
レプリカセットの設定
[root@db1 mongodb]# ./bin/mongo --port 27011 --eval "rs.initiate()"
MongoDB shell version: 3.2.9
connecting to: 127.0.0.1:27011/test
{
"info2" : "no configuration specified. Using a default configuration for the set",
"me" : "db1:27011",
"ok" : 1
}
[root@db1 mongodb]# ./bin/mongo --port 27011 --eval "rs.add('db2:27011')"
MongoDB shell version: 3.2.9
connecting to: 127.0.0.1:27011/test
{ "ok" : 1 }
[root@db1 mongodb]# ./bin/mongo --port 27011 --eval "rs.addArb('db3:27011')"
MongoDB shell version: 3.2.9
connecting to: 127.0.0.1:27011/test
{ "ok" : 1 }
[root@db1 mongodb]# ./bin/mongo --port 27011 --eval "var config = rs.config(); config.members[0].priority=2; rs.reconfig(config);"
MongoDB shell version: 3.2.9
connecting to: 127.0.0.1:27011/test
{ "ok" : 1 }
[root@db1 mongodb]# ./bin/mongo --port 27011 --eval "rs.status()"
MongoDB shell version: 3.2.9
connecting to: 127.0.0.1:27011/test
{
"set" : "rs01",
"date" : ISODate("2017-01-29T05:19:51.778Z"),
"myState" : 1,
"term" : NumberLong(1),
"heartbeatIntervalMillis" : NumberLong(2000),
"members" : [
{
"_id" : 0,
"name" : "db1:27011",
"health" : 1,
"state" : 1,
"stateStr" : "PRIMARY",
"uptime" : 784,
"optime" : {
"ts" : Timestamp(1485667161, 1),
"t" : NumberLong(1)
},
"optimeDate" : ISODate("2017-01-29T05:19:21Z"),
"electionTime" : Timestamp(1485666794, 2),
"electionDate" : ISODate("2017-01-29T05:13:14Z"),
"configVersion" : 4,
"self" : true
},
{
"_id" : 1,
"name" : "db2:27011",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 328,
"optime" : {
"ts" : Timestamp(1485667161, 1),
"t" : NumberLong(1)
},
"optimeDate" : ISODate("2017-01-29T05:19:21Z"),
"lastHeartbeat" : ISODate("2017-01-29T05:19:49.930Z"),
"lastHeartbeatRecv" : ISODate("2017-01-29T05:19:49.929Z"),
"pingMs" : NumberLong(10),
"syncingTo" : "db1:27011",
"configVersion" : 4
},
{
"_id" : 2,
"name" : "db3:27011",
"health" : 1,
"state" : 7,
"stateStr" : "ARBITER",
"uptime" : 317,
"lastHeartbeat" : ISODate("2017-01-29T05:19:51.680Z"),
"lastHeartbeatRecv" : ISODate("2017-01-29T05:19:51.672Z"),
"pingMs" : NumberLong(0),
"configVersion" : 4
}
],
"ok" : 1
}
サンプルデータの投入と確認
Primary(db1)にデータ投入
[root@db1 mongodb]# ./bin/mongo --port 27011
MongoDB shell version: 3.2.9
connecting to: 127.0.0.1:27011/test
rs01:PRIMARY> use mydb
switched to db mydb
rs01:PRIMARY> for(var i=0; i<10000; i++) db.logs.insert({"uid":i, "value":Math.floor(Math.random()*10000+1)})
WriteResult({ "nInserted" : 1 })
rs01:PRIMARY> db.logs.count()
10000
Secondary(db2)で確認
[root@db2 mongodb]# ./bin/mongo localhost:27011/mydb
MongoDB shell version: 3.2.9
connecting to: localhost:27011/mydb
rs01:SECONDARY> db.getMongo().setSlaveOk()
rs01:SECONDARY> db.logs.count()
10000
pymongoで確認
localhostからEC2へリクエストする
$ python -V
Python 3.5.1
$ pip list | grep pymongo
pymongo (3.4.0)
下記のようなコードを書いて実行する。
(/etc/hosts以下に名前解決できるように記述をしている。)
from pymongo import MongoClient
from time import sleep
c = MongoClient(host=['db1:27011', 'db2:27011', 'db3:27011'], replicaset='rs01')
print(c.mydb.logs.count())
print(c.nodes)
$ python req.py
10000
frozenset({('db1', 27011), ('db3', 27011), ('db2', 27011)})
ためしにPrimary(db1)を落としてみる
[root@db1 mongodb]# pgrep -lf mongo
2654 ./bin/mongod -f conf/rs01.conf
[root@db1 mongodb]# pkill -f mongo
[root@db1 mongodb]# pgrep -lf mongo
[root@db1 mongodb]#
db2がPrimaryに昇格している
[root@db2 mongodb]# ./bin/mongo localhost:27011/mydb --eval "rs.status()"
MongoDB shell version: 3.2.9
connecting to: localhost:27011/mydb
{
"set" : "rs01",
"date" : ISODate("2017-01-29T05:58:54.369Z"),
"myState" : 1,
"term" : NumberLong(2),
"heartbeatIntervalMillis" : NumberLong(2000),
"members" : [
{
"_id" : 0,
"name" : "db1:27011",
"health" : 0,
"state" : 8,
"stateStr" : "(not reachable/healthy)",
"uptime" : 0,
"optime" : {
"ts" : Timestamp(0, 0),
"t" : NumberLong(-1)
},
"optimeDate" : ISODate("1970-01-01T00:00:00Z"),
"lastHeartbeat" : ISODate("2017-01-29T05:58:53.729Z"),
"lastHeartbeatRecv" : ISODate("2017-01-29T05:58:19.930Z"),
"pingMs" : NumberLong(0),
"lastHeartbeatMessage" : "Connection refused",
"configVersion" : -1
},
{
"_id" : 1,
"name" : "db2:27011",
"health" : 1,
"state" : 1,
"stateStr" : "PRIMARY",
"uptime" : 3108,
"optime" : {
"ts" : Timestamp(1485669512, 1),
"t" : NumberLong(2)
},
"optimeDate" : ISODate("2017-01-29T05:58:32Z"),
"infoMessage" : "could not find member to sync from",
"electionTime" : Timestamp(1485669511, 1),
"electionDate" : ISODate("2017-01-29T05:58:31Z"),
"configVersion" : 4,
"self" : true
},
{
"_id" : 2,
"name" : "db3:27011",
"health" : 1,
"state" : 7,
"stateStr" : "ARBITER",
"uptime" : 2659,
"lastHeartbeat" : ISODate("2017-01-29T05:58:53.712Z"),
"lastHeartbeatRecv" : ISODate("2017-01-29T05:58:52.564Z"),
"pingMs" : NumberLong(0),
"configVersion" : 4
}
],
"ok" : 1
}
リクエストは問題なく処理されている
from pymongo import MongoClient
from time import sleep
c = MongoClient(host=['db1:27011', 'db2:27011', 'db3:27011'], replicaset='rs01')
print(c.mydb.logs.count())
print(c.nodes)
$ python req.py
10000
frozenset({('db3', 27011), ('db2', 27011)})