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Failed to initialize pool: Communications link failure

See original GitHub issue

Question

I deployed sharding-proxy in kubernetes, and the database was also deployed in kubernetes. Now I use coreDNS with kubernetes to do DNS resolution, but the service reported an error. The error log is as follows

Exception in thread "main" org.apache.shardingsphere.core.exception.ShardingException: Can not build data source, name is ds_master.

at org.apache.shardingsphere.shardingproxy.backend.communication.jdbc.datasource.JDBCBackendDataSource.createDataSources(JDBCBackendDataSource.java:79)`
at org.apache.shardingsphere.shardingproxy.backend.communication.jdbc.datasource.JDBCBackendDataSource.(JDBCBackendDataSource.java:67)

at org.apache.shardingsphere.shardingproxy.backend.schema.LogicSchema.(LogicSchema.java:63)

at org.apache.shardingsphere.shardingproxy.backend.schema.impl.MasterSlaveSchema.(MasterSlaveSchema.java:58)

at org.apache.shardingsphere.shardingproxy.backend.schema.LogicSchemaFactory.newInstance(LogicSchemaFactory.java:59)

at org.apache.shardingsphere.shardingproxy.backend.schema.LogicSchemas.initSchemas(LogicSchemas.java:104)

at org.apache.shardingsphere.shardingproxy.backend.schema.LogicSchemas.init(LogicSchemas.java:94)

at org.apache.shardingsphere.shardingproxy.backend.schema.LogicSchemas.init(LogicSchemas.java:78)

at org.apache.shardingsphere.shardingproxy.Bootstrap.startWithoutRegistryCenter(Bootstrap.java:101)

at org.apache.shardingsphere.shardingproxy.Bootstrap.main(Bootstrap.java:81)

Caused by: com.zaxxer.hikari.pool.HikariPool$PoolInitializationException: Failed to initialize pool: Communications link failure

at com.zaxxer.hikari.pool.HikariPool.throwPoolInitializationException(HikariPool.java:528)

at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:520)

at com.zaxxer.hikari.pool.HikariPool.(HikariPool.java:112)

at com.zaxxer.hikari.HikariDataSource.(HikariDataSource.java:72)

at org.apache.shardingsphere.shardingproxy.backend.communication.jdbc.datasource.JDBCRawBackendDataSourceFactory.build(JDBCRawBackendDataSourceFactory.java:77)

at org.apache.shardingsphere.shardingproxy.backend.communication.jdbc.datasource.JDBCBackendDataSource.createDataSources(JDBCBackendDataSource.java:75)

... 9 more

Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:526)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)

at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:990)

at com.mysql.jdbc.MysqlIO.(MysqlIO.java:342)

at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2197)

at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230)

at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025)

at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:778)

at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:47)

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:526)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)

at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386)

at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)

at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:95)

at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:101)

at com.zaxxer.hikari.pool.PoolBase.newConnection(PoolBase.java:341)

at com.zaxxer.hikari.pool.PoolBase.newPoolEntry(PoolBase.java:193)

at com.zaxxer.hikari.pool.HikariPool.createPoolEntry(HikariPool.java:428)

at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:499)

My configuration file is as follows config-master_slave.yaml

schemaName: master_slave_db

dataSources:
  ds_master:
    url: jdbc:mysql://master-aaa.test:3306/lly
    username: root
    password: root
    connectionTimeoutMilliseconds: 30000
    idleTimeoutMilliseconds: 60000
    maxLifetimeMilliseconds: 1800000
    maxPoolSize: 65
  ds_slave0:
    url: jdbc:mysql://slave-aaa.test:3306/lly
    username: root
    password: root
    connectionTimeoutMilliseconds: 30000
    idleTimeoutMilliseconds: 60000
    maxLifetimeMilliseconds: 1800000
    maxPoolSize: 65

masterSlaveRule:
  name: ds_ms
  masterDataSourceName: ds_master
  slaveDataSourceNames:
    - ds_slave0

server.yaml

authentication:
  users:
    root:
      password: root

props:
  sql.show: true

Dockerfile

FROM apache/sharding-proxy:latest
COPY mysql-connector-java-5.1.47.jar /opt/sharding-proxy/lib/

I used docker-compose to launch, no problem

docker-compose.yaml

version: '3.1'
services:
  mysql-master:
    restart: always
    image: sharding-proxy:v5
    container_name: sharding-proxy
    ports:
      - 3312:3307
    volumes:
      - ./conf:/opt/sharding-proxy/conf
    networks:
      - sharding-proxy

networks:
  sharding-proxy:
    external:
      name: mysqltest

config-xxx.yaml

schemaName: master_slave_db2

dataSources:
  ds_master:
    url: jdbc:mysql://mysql-master:3306/cloud-master
    username: root
    password: root
    connectionTimeoutMilliseconds: 30000
    idleTimeoutMilliseconds: 60000
    maxLifetimeMilliseconds: 1800000
    maxPoolSize: 65
  ds_slave0:
    url: jdbc:mysql://mysql-slave:3306/cloud-master
    username: root
    password: root
    connectionTimeoutMilliseconds: 30000
    idleTimeoutMilliseconds: 60000
    maxLifetimeMilliseconds: 1800000
    maxPoolSize: 65

masterSlaveRule:
  name: ds_ms1
  masterDataSourceName: ds_master
  slaveDataSourceNames:
    - ds_slave0

Thank you for your answers

Issue Analytics

State:
Created 3 years ago
Comments:8 (3 by maintainers)

Top GitHub Comments

2reactions

huntunshulecommented, Apr 26, 2020

I have solved this problem, thank you, my k8s system deployment file is as follows for reference

kind: Deployment
apiVersion: extensions/v1beta1
metadata:
  name: shardingproxy-{{.Values.projectname}}
spec:
  replicas: 1
  template:
    metadata:
      labels:
        name: shard-{{.Values.projectname}}
    spec:
      containers:
      - name: sharding-{{.Values.projectname}}
        image: sharding-proxy:v5
        imagePullPolicy: IfNotPresent
        volumeMounts:
        - name: {{.Values.projectname}}-conf
          mountPath: /opt/sharding-proxy/conf
        - name: localtime
          mountPath: /etc/localtime
        ports:
        - name: sharding-proxy
          containerPort: 3307
        livenessProbe:
          tcpSocket:
            port: 3307
          initialDelaySeconds: 15
          periodSeconds: 20
      initContainers:
      - name: init-mysqlmaster
        image: busybox:latest
        command: ['sh', '-c', 'until telnet master-{{.Values.projectname}}.{{.Release.Namespace}}:3306; do echo waiting for mysql; sleep 10; done;']
      - name: init-mysqlslave
        image: busybox:latest
        command: ['sh', '-c', 'until telnet slave-{{.Values.projectname}}.{{.Release.Namespace}}:3306; do echo waiting for mysql; sleep 10; done;']
      volumes:
        - name: {{.Values.projectname}}-conf
          configMap:
           name: "{{.Values.conf}}"
        - name: localtime
          hostPath:
            path: /usr/share/zoneinfo/Asia/Shanghai

0reactions

huntunshulecommented, Apr 26, 2020

Yaml file for sharding - proxy

kind: Deployment
apiVersion: extensions/v1beta1
metadata:
  name: shardingproxy-{{.Values.projectname}}
spec:
  replicas: 2
  template:
    metadata:
      labels:
        name: shard-{{.Values.projectname}}
    spec:
      containers:
      - name: sharding-{{.Values.projectname}}
        image: sharding-proxy:v5
        imagePullPolicy: IfNotPresent
        volumeMounts:
        - name: {{.Values.projectname}}-conf
          mountPath: /opt/sharding-proxy/conf
        ports:
        - name: sharding-proxy
          containerPort: 3307
        livenessProbe:
          tcpSocket:
            port: 3307
          initialDelaySeconds: 15
          periodSeconds: 20
      volumes:
        - name: {{.Values.projectname}}-conf
          configMap:
           name: "{{.Values.conf}}"

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