Mongodb second call -- implementation of mongodb high availability cluster

Main records of this paper MongoDB Cluster building

Bad environment preparation ：liunx centos7,docker-compose, Mirror image mongo:4.2.21.
One master and one slave Arbitration , In one machine

project	Value
0.221:27017	node 1
0.221:27018	node 2
0.221:27019	Arbitration node

1. docker-compose.yaml

version: '3.7'
services:
  mongo01:
    image: mongo:4.2.21
    container_name: mongo01
    ports:
    - "27017:27017"
    environment:
    - TZ=Asia/Shanghai
    volumes:
    - ./rs1:/data/db
    #--replSet newset  Define replica set name   Can be used after the path ?replicaSet=newset
    command: mongod --dbpath /data/db --replSet newset --oplogSize 128
    networks:
    - my-net
  mongo02:
    image: mongo:4.2.21
    container_name: mongo02
    ports:
    - "27018:27017"
    environment:
    - TZ=Asia/Shanghai
    volumes:
    - ./rs2:/data/db
    command: mongod --dbpath /data/db --replSet newset  --oplogSize 128
    networks:
    - my-net
  myarbiter:
    image: mongo:4.2.21
    container_name: myarbiter
    ports:
    - "27019:27017"
    environment:
    - TZ=Asia/Shanghai
    volumes:
    - ./rs3:/data/db
    command: mongod --dbpath /data/db --replSet newset  --oplogSize 128
    networks:
    - my-net
  mongo-console:
    image: mongo-express
    container_name: mongo-console
    ports:
    - "8081:8081"
    environment:
    # Console   Only after the cluster takes effect can the connection succeed   You can only connect to master  Can be pulled out alone 
    - ME_CONFIG_MONGODB_SERVER=mongo01
# - ME_CONFIG_BASICAUTH_USERNAME=admin
# - ME_CONFIG_BASICAUTH_PASSWORD=admin
    - TZ=Asia/Shanghai
    networks:
    - my-net
networks:
  # New network   Internal service name call 
  my-net:
    external: true

2. Start the container

[[email protected] mongo-cluster]# docker ps -a
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                      NAMES
7588aac35621        mongo:4.2.21        "docker-entrypoint.s…"   15 minutes ago      Up 8 minutes        0.0.0.0:27017->27017/tcp   mongo01
5adca1bbfa3d        mongo:4.2.21        "docker-entrypoint.s…"   15 minutes ago      Up 15 minutes       0.0.0.0:27019->27017/tcp   myarbiter
5384dac6d37a        mongo:4.2.21        "docker-entrypoint.s…"   15 minutes ago      Up 15 minutes       0.0.0.0:27018->27017/tcp   mongo02
5df1b5d9af4f        mongo-express       "tini -- /docker-ent…"   15 minutes ago      Up 8 minutes        0.0.0.0:8081->8081/tcp     mongo-console

3. Initialize cluster

# Enter any container   perform mongo command 
[[email protected] mongo-cluster]# docker exec -it mongo02 mongo
MongoDB shell version v4.2.21
# Perform the initial configuration of the cluster , If you need program connection , You need to fill in the host IP
>rs.initiate({
    _id:"newset",members:[{
    _id:0,host:"192.168.0.221:27017"},{
    _id:1,host:"192.168.0.221:27018"},{
    _id:2,host:"192.168.0.221:27019",arbiterOnly:true}]})
{
    
	"operationTime" : Timestamp(1656417751, 1),
	"ok" : 0,
	"errmsg" : "already initialized",
	"code" : 23,
	"codeName" : "AlreadyInitialized",
	"$clusterTime" : {
    
		"clusterTime" : Timestamp(1656417751, 1),
		"signature" : {
    
			"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
			"keyId" : NumberLong(0)
		}
	}
}
newset:SECONDARY> 

_id： Corresponding replSet name
host： If you need program connection , You need to fill in the host IP
arbiterOnly:true Indicates that this node is an arbitration node

4. View the cluster status

newset:SECONDARY> rs.status()
# find members Node information 
"members" : [
		{
    
			"_id" : 0,
			"name" : "192.168.0.221:27017",
			"health" : 1,
			"state" : 1,
			# colony master
			"stateStr" : "PRIMARY",
			"uptime" : 202,
			"optime" : {
    
				"ts" : Timestamp(1656417761, 6),
				"t" : NumberLong(1)
			},
			"optimeDate" : ISODate("2022-06-28T12:02:41Z"),
			"syncingTo" : "",
			"syncSourceHost" : "",
			"syncSourceId" : -1,
			"infoMessage" : "could not find member to sync from",
			"electionTime" : Timestamp(1656417761, 1),
			"electionDate" : ISODate("2022-06-28T12:02:41Z"),
			"configVersion" : 1,
			"self" : true,
			"lastHeartbeatMessage" : ""
		},
		{
    
			"_id" : 1,
			"name" : "192.168.0.221:27018",
			"health" : 1,
			"state" : 2,
			# colony slave
			"stateStr" : "SECONDARY",
			"uptime" : 10,
			"optime" : {
    
				"ts" : Timestamp(1656417751, 1),
				"t" : NumberLong(-1)
			},
			"optimeDurable" : {
    
				"ts" : Timestamp(1656417751, 1),
				"t" : NumberLong(-1)
			},
			"optimeDate" : ISODate("2022-06-28T12:02:31Z"),
			"optimeDurableDate" : ISODate("2022-06-28T12:02:31Z"),
			"lastHeartbeat" : ISODate("2022-06-28T12:02:41.778Z"),
			"lastHeartbeatRecv" : ISODate("2022-06-28T12:02:41.434Z"),
			"pingMs" : NumberLong(0),
			"lastHeartbeatMessage" : "",
			"syncingTo" : "",
			"syncSourceHost" : "",
			"syncSourceId" : -1,
			"infoMessage" : "",
			"configVersion" : 1
		},
		{
    
			"_id" : 2,
			"name" : "192.168.0.221:27019",
			"health" : 1,
			"state" : 7,
			# Cluster arbitration 
			"stateStr" : "ARBITER",
			"uptime" : 10,
			"lastHeartbeat" : ISODate("2022-06-28T12:02:41.778Z"),
			"lastHeartbeatRecv" : ISODate("2022-06-28T12:02:41.704Z"),
			"pingMs" : NumberLong(0),
			"lastHeartbeatMessage" : "",
			"syncingTo" : "",
			"syncSourceHost" : "",
			"syncSourceId" : -1,
			"infoMessage" : "",
			"configVersion" : 1
		}
	],

5. simulation master Node down

Stop master node , Get into slave View the status in the node container

"members" : [
		{
    
			"_id" : 0,
			"name" : "192.168.0.221:27017",
			"health" : 0,
			"state" : 8,
			"stateStr" : "(not reachable/healthy)",
			"uptime" : 0,
			"optime" : {
    
				"ts" : Timestamp(0, 0),
				"t" : NumberLong(-1)
			},
			"optimeDurable" : {
    
				"ts" : Timestamp(0, 0),
				"t" : NumberLong(-1)
			},
			"optimeDate" : ISODate("1970-01-01T00:00:00Z"),
			"optimeDurableDate" : ISODate("1970-01-01T00:00:00Z"),
			"lastHeartbeat" : ISODate("2022-06-28T12:05:49.005Z"),
			"lastHeartbeatRecv" : ISODate("2022-06-28T12:05:30.416Z"),
			"pingMs" : NumberLong(0),
			"lastHeartbeatMessage" : "Error connecting to 192.168.0.221:27017 :: caused by :: Connection refused",
			"syncingTo" : "",
			"syncSourceHost" : "",
			"syncSourceId" : -1,
			"infoMessage" : "",
			"configVersion" : -1
		},
		{
    
			"_id" : 1,
			"name" : "192.168.0.221:27018",
			"health" : 1,
			"state" : 1,
			# The original slave The node has been changed to master 了 
			"stateStr" : "PRIMARY",
			"uptime" : 390,
			"optime" : {
    
				"ts" : Timestamp(1656417940, 2),
				"t" : NumberLong(3)
			},
			"optimeDate" : ISODate("2022-06-28T12:05:40Z"),
			"syncingTo" : "",
			"syncSourceHost" : "",
			"syncSourceId" : -1,
			"infoMessage" : "could not find member to sync from",
			"electionTime" : Timestamp(1656417940, 1),
			"electionDate" : ISODate("2022-06-28T12:05:40Z"),
			"configVersion" : 1,
			"self" : true,
			"lastHeartbeatMessage" : ""
		},
		{
    
			"_id" : 2,
			"name" : "192.168.0.221:27019",
			"health" : 1,
			"state" : 7,
			"stateStr" : "ARBITER",
			"uptime" : 197,
			"lastHeartbeat" : ISODate("2022-06-28T12:05:49.006Z"),
			"lastHeartbeatRecv" : ISODate("2022-06-28T12:05:48.204Z"),
			"pingMs" : NumberLong(0),
			"lastHeartbeatMessage" : "",
			"syncingTo" : "",
			"syncSourceHost" : "",
			"syncSourceId" : -1,
			"infoMessage" : "",
			"configVersion" : 1
		}
	],

You can see the original slave The node has become PRIMARY Master node

6.mongo-express Console

1. Connection points needing attention

    environment:
    # No ports   Go directly to the container name 
    - ME_CONFIG_MONGODB_SERVER=mongo01

2. The cluster is not initialized or the cluster master Has changed , The console will report the following error

(node:6) UnhandledPromiseRejectionWarning: MongoError: not master and slaveOk=false

You need to determine master After the node, restart the console

7.springboot Cluster configuration in

spring:
  data:
    mongodb:
      # There is a password connection   If the account password contains special characters, you need to use URLEncoder code   Database name is required 
      #uri: mongodb://admin:[email protected]:27017/imgdb
      # The cluster approach   Replica set replicaSet Take it or not 
      uri: mongodb://192.168.0.221:27017,192.168.0.221:27018/imgdb?replicaSet=newset
# uri: mongodb://192.168.0.221:27017/imgdb

That's all for this chapter .

Last one ：MongoDB First words – Docker install MongoDB as well as Springboot Integrate MongoDB
Next ：JVM First words – JVM Introduction details and runtime data area analysis

There is a good way to study , There's no end to learning how to make a boat