Install Zookeeper under Docker (standalone and cluster)

Install Zookeeper under Docker (standalone and cluster)

After starting Docker, let's take a look at the options we have.

If there is an official one, of course choose the official one.

download:

[root@localhost admin]# docker pull zookeeper
Using default tag: latest
Trying to pull repository docker.io/library/zookeeper ...
latest: Pulling from docker.io/library/zookeeper
1ab2bdfe9778: Already exists
7aaf9a088d61: Pull complete
80a55c9c9fe8: Pull complete
a0086b0e6eec: Pull complete
4165e7457cad: Pull complete
bcba13bcf3a1: Pull complete
41c03a109e47: Pull complete
4d5281c6b0d4: Pull complete
Digest: sha256:175d6bb1471e1e37a48bfa41a9da047c80fade60fd585eae3a0e08a4ce1d39ed
Status: Downloaded newer image for docker.io/zookeeper:latest

View image details

[root@localhost admin]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
192.168.192.128:443/hello-2 latest 0c24558dd388 42 hours ago 660 MB
192.168.192.128:443/hello latest a3ba3d430bed 42 hours ago 660 MB
docker.io/nginx latest 5a3221f0137b 13 days ago 126 MB
docker.io/zookeeper latest 3487af26dee9 13 days ago 225 MB
docker.io/registry latest f32a97de94e1 5 months ago 25.8 MB
docker.io/mongo latest 8bf72137439e 12 months ago 380 MB
docker.io/influxdb latest 34de2bdc2d7f 12 months ago 213 MB
docker.io/centos latest 5182e96772bf 12 months ago 200 MB
docker.io/grafana/grafana latest 3e16e05be9a3 13 months ago 245 MB
docker.io/hello-world latest 2cb0d9787c4d 13 months ago 1.85 kB
docker.io/java latest d23bdf5b1b1b 2 years ago 643 MB
[root@localhost admin]# docker inspect 3487af26dee9
[
  {
    "Id": "sha256:3487af26dee9ef9eacee9a97521bc4f0243bef0b285247258c32f4a03cab92c5",
    "RepoTags": [
      "docker.io/zookeeper:latest"
    ],
    "RepoDigests": [
      "docker.io/zookeeper@sha256:175d6bb1471e1e37a48bfa41a9da047c80fade60fd585eae3a0e08a4ce1d39ed"
    ],
    "Parent": "",
    "Comment": "",
    "Created": "2019-08-15T06:10:50.178554969Z",
    "Container": "9a38467115f1952161d6075135d5c5287967282b834cfe68183339c810f9652b",
    "ContainerConfig": {
      "Hostname": "9a38467115f1",
      "Domainname": "",
      "User": "",
      "AttachStdin": false,
      "AttachStdout": false,
      "AttachStderr": false,
      "ExposedPorts": {
        "2181/tcp": {},
        "2888/tcp": {},
        "3888/tcp": {},
        "8080/tcp": {}
      },
      "Tty": false,
      "OpenStdin": false,
      "StdinOnce": false,
      "Env": [
        "PATH=/usr/local/openjdk-8/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/apache-zookeeper-3.5.5-bin/bin",
        "LANG=C.UTF-8",
        "JAVA_HOME=/usr/local/openjdk-8",
        "JAVA_VERSION=8u222",
        "JAVA_BASE_URL=https://github.com/AdoptOpenJDK/openjdk8-upstream-binaries/releases/download/jdk8u222-b10/OpenJDK8U-jre_",
        "JAVA_URL_VERSION=8u222b10",
        "ZOO_CONF_DIR=/conf",
        "ZOO_DATA_DIR=/data",
        "ZOO_DATA_LOG_DIR=/datalog",
        "ZOO_LOG_DIR=/logs",
        "ZOO_TICK_TIME=2000",
        "ZOO_INIT_LIMIT=5",
        "ZOO_SYNC_LIMIT=2",
        "ZOO_AUTOPURGE_PURGEINTERVAL=0",
        "ZOO_AUTOPURGE_SNAPRETAINCOUNT=3",
        "ZOO_MAX_CLIENT_CNXNS=60",
        "ZOO_STANDALONE_ENABLED=true",
        "ZOO_ADMINSERVER_ENABLED=true",
        "ZOOCFGDIR=/conf"
      ],
      "Cmd": [
        "/bin/sh",
        "-c",
        "#(nop) ",
        "CMD [\"zkServer.sh\" \"start-foreground\"]"
      ],
      "ArgsEscaped": true,
      "Image": "sha256:20bf3cc1bd5b5766b79da5265e94007d0802ce241df1636d0f63e211a79a0e3e",
      "Volumes": {
        "/data": {},
        "/datalog": {},
        "/logs": {}
      },
      "WorkingDir": "/apache-zookeeper-3.5.5-bin",
      "Entrypoint": [
        "/docker-entrypoint.sh"
      ],
      "OnBuild": null,
      "Labels": {}
    },
    "DockerVersion": "18.06.1-ce",
    "Author": "",
    "Config": {
      "Hostname": "",
      "Domainname": "",
      "User": "",
      "AttachStdin": false,
      "AttachStdout": false,
      "AttachStderr": false,
      "ExposedPorts": {
        "2181/tcp": {},
        "2888/tcp": {},
        "3888/tcp": {},
        "8080/tcp": {}
      },
      "Tty": false,
      "OpenStdin": false,
      "StdinOnce": false,
      "Env": [
        "PATH=/usr/local/openjdk-8/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/apache-zookeeper-3.5.5-bin/bin",
        "LANG=C.UTF-8",
        "JAVA_HOME=/usr/local/openjdk-8",
        "JAVA_VERSION=8u222",
        "JAVA_BASE_URL=https://github.com/AdoptOpenJDK/openjdk8-upstream-binaries/releases/download/jdk8u222-b10/OpenJDK8U-jre_",
        "JAVA_URL_VERSION=8u222b10",
        "ZOO_CONF_DIR=/conf",
        "ZOO_DATA_DIR=/data",
        "ZOO_DATA_LOG_DIR=/datalog",
        "ZOO_LOG_DIR=/logs",
        "ZOO_TICK_TIME=2000",
        "ZOO_INIT_LIMIT=5",
        "ZOO_SYNC_LIMIT=2",
        "ZOO_AUTOPURGE_PURGEINTERVAL=0",
        "ZOO_AUTOPURGE_SNAPRETAINCOUNT=3",
        "ZOO_MAX_CLIENT_CNXNS=60",
        "ZOO_STANDALONE_ENABLED=true",
        "ZOO_ADMINSERVER_ENABLED=true",
        "ZOOCFGDIR=/conf"
      ],
      "Cmd": [
        "zkServer.sh",
        "start-foreground"
      ],
      "ArgsEscaped": true,
      "Image": "sha256:20bf3cc1bd5b5766b79da5265e94007d0802ce241df1636d0f63e211a79a0e3e",
      "Volumes": {
        "/data": {},
        "/datalog": {},
        "/logs": {}
      },
      "WorkingDir": "/apache-zookeeper-3.5.5-bin",
      "Entrypoint": [
        "/docker-entrypoint.sh"
      ],
      "OnBuild": null,
      "Labels": null
    },
    "Architecture": "amd64",
    "Os": "linux",
    "Size": 225126346,
    "VirtualSize": 225126346,
    "GraphDriver": {
      "Name": "overlay2",
      "Data": {
        "LowerDir": "/var/lib/docker/overlay2/92185ebf7638a7b34180cfb87795dd758405cbad4fd0139b92a227d1a4b61847/diff:/var/lib/docker/overlay2/8787e91f5c03a7c03cee072019eca49a0402a0a0902be39ed0b5d651a79cce35/diff:/var/lib/docker/overlay2/ce5864ddfa4d1478047aa9fcaa03744e8a4078ebe43b41e7836c96c54c724044/diff:/var/lib/docker/overlay2/fc99437bcfbabb9e8234c06c90d1c60e58c34ac053aff1adc368b7ad3a50c158/diff:/var/lib/docker/overlay2/1779297a8980830229bd4bf58bd741730956d6797332fd07b863a1b48dcb6fa2/diff:/var/lib/docker/overlay2/ee735aa3608d890ac4751dd93581a67cb54a5dd4714081e9d09d0ebd9dbc3501/diff:/var/lib/docker/overlay2/cf6b3cbc42f3c8d1fb09b29db0dafbb4dceb120925970ab8a3871eaa8562414c/diff",
        "MergedDir": "/var/lib/docker/overlay2/a7fcc1b78c472cde943f20d1d4495f145308507b5fe3da8800c33dc4ce426156/merged",
        "UpperDir": "/var/lib/docker/overlay2/a7fcc1b78c472cde943f20d1d4495f145308507b5fe3da8800c33dc4ce426156/diff",
        "WorkDir": "/var/lib/docker/overlay2/a7fcc1b78c472cde943f20d1d4495f145308507b5fe3da8800c33dc4ce426156/work"
      }
    },
    "RootFS": {
      "Type": "layers",
      "Layers": [
        "sha256:1c95c77433e8d7bf0f519c9d8c9ca967e2603f0defbf379130d9a841cca2e28e",
        "sha256:2bf534399acac9c6b09a0b1d931223808000b04400a749f08187ed9ee435738d",
        "sha256:eb25e0278d41b9ac637d8cb2e391457cf44ce8d2bfe0646d0c9faefc96413f91",
        "sha256:e54bd3566d9ef3e1309a5af6caf8682f32c6ac4d6adfcbd3e601cfee4e2e0e85",
        "sha256:c79435051d529a7b86f5f9fc32e7e2ec401929434e5596f02a2af731f55c9f28",
        "sha256:76e0d7b2d700e6d17924b985703c7b5b84fb39ddcc0a1181b41217c2a11dffc4",
        "sha256:eecdc37df6afd77091641588f9639f63b65e8eb141e56529e00da44419c5bd04",
        "sha256:36e788f2d91a89375df5901f31cca33776f887c00ddfd3cf9f2466fa4cb794d6"
      ]
    }
  }
]

The default pull is the latest version 3.5.X. If you need version 3.4.X, you need to specify the tag

Single Machine

# The last one is the image ID [root@localhost admin]# docker run -d -p 2181:2181 --name some-zookeeper --restart always 3487af26dee9
d5c6f857cd88c342acf63dd58e838a4cdf912daa6c8c0115091147136e819307
[root@localhost admin]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
d5c6f857cd88 3487af26dee9 "/docker-entrypoint..." 4 seconds ago Up 3 seconds 2888/tcp, 3888/tcp, 0.0.0.0:2181->2181/tcp, 8080/tcp some-zookeeper
[root@localhost admin]# docker exec -it d5c6f857cd88 bash
root@d5c6f857cd88:/apache-zookeeper-3.5.5-bin# ./bin/zkCli.sh
Connecting to localhost:2181
2019-08-29 07:15:21,623 [myid:] - INFO [main:Environment@109] - Client environment:zookeeper.version=3.5.5-390fe37ea45dee01bf87dc1c042b5e3dcce88653, built on 05/03/2019 12:07 GMT
2019-08-29 07:15:21,679 [myid:] - INFO [main:Environment@109] - Client environment:host.name=d5c6f857cd88
2019-08-29 07:15:21,680 [myid:] - INFO [main:Environment@109] - Client environment:java.version=1.8.0_222
2019-08-29 07:15:21,717 [myid:] - INFO [main:Environment@109] - Client environment:java.vendor=Oracle Corporation
2019-08-29 07:15:21,718 [myid:] - INFO [main:Environment@109] - Client environment:java.home=/usr/local/openjdk-8
2019-08-29 07:15:21,725 ​​[myid:] - INFO [main:Environment@109] - Client environment:java.class.path=/apache-zookeeper-3.5.5-bin/bin/../zookeeper-server/target/classes:/apache-zookeeper-3.5.5-bin/bin/../build/classes:/apache-zookeeper-3.5.5-bin/bin/../zookeeper-server/target/lib/*.jar:/apache-zookeeper-3.5.5-bin/bin/../build/lib/*.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/zookeeper-jute-3.5.5.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/zookeeper-3.5.5.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/slf4j-log4j12-1.7.25.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/slf4j-api-1.7.25.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/netty-all-4.1.29.Final.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/log4j-1.2.17.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/json-simple-1.1.1.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jline-2.11.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jetty-util-9.4.17.v20190418.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jetty-servlet-9.4.17.v20190418.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jetty-server-9.4.17.v20190418.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jetty-security-9.4.17.v20190418.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jetty-io-9.4.17.v20190418.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jetty-http-9.4.17.v20190418.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/javax.servlet-api-3.1.0.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jackson-databind-2.9.8.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jackson-core-2.9.8.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/jackson-annotations-2.9.0.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/commons-cli-1.2.jar:/apache-zookeeper-3.5.5-bin/bin/../lib/audience-annotations-0.5.0.jar:/apache-zookeeper-3.5.5-bin/bin/../zookeeper-*.jar:/apache-zookeeper-3.5.5-bin/bin/../zookeeper-server/src/main/resources/lib/*.jar:/conf:
2019-08-29 07:15:22,108 [myid:] - INFO [main:Environment@109] - Client environment:java.library.path=/usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib
2019-08-29 07:15:22,109 [myid:] - INFO [main:Environment@109] - Client environment:java.io.tmpdir=/tmp
2019-08-29 07:15:22,109 [myid:] - INFO [main:Environment@109] - Client environment:java.compiler=<NA>
2019-08-29 07:15:22,109 [myid:] - INFO [main:Environment@109] - Client environment:os.name=Linux
2019-08-29 07:15:22,109 [myid:] - INFO [main:Environment@109] - Client environment:os.arch=amd64
2019-08-29 07:15:22,110 [myid:] - INFO [main:Environment@109] - Client environment:os.version=3.10.0-862.9.1.el7.x86_64
2019-08-29 07:15:22,110 [myid:] - INFO [main:Environment@109] - Client environment:user.name=root
2019-08-29 07:15:22,110 [myid:] - INFO [main:Environment@109] - Client environment:user.home=/root
2019-08-29 07:15:22,110 [myid:] - INFO [main:Environment@109] - Client environment:user.dir=/apache-zookeeper-3.5.5-bin
2019-08-29 07:15:22,118 [myid:] - INFO [main:Environment@109] - Client environment:os.memory.free=11MB
2019-08-29 07:15:22,148 [myid:] - INFO [main:Environment@109] - Client environment:os.memory.max=247MB
2019-08-29 07:15:22,148 [myid:] - INFO [main:Environment@109] - Client environment:os.memory.total=15MB
2019-08-29 07:15:22,206 [myid:] - INFO [main:ZooKeeper@868] - Initiating client connection, connectString=localhost:2181 sessionTimeout=30000 watcher=org.apache.zookeeper.ZooKeeperMain$MyWatcher@3b95a09c
2019-08-29 07:15:22,239 [myid:] - INFO [main:X509Util@79] - Setting -D jdk.tls.rejectClientInitiatedRenegotiation=true to disable client-initiated TLS renegotiation
2019-08-29 07:15:22,285 [myid:] - INFO [main:ClientCnxnSocket@237] - jute.maxbuffer value is 4194304 Bytes
2019-08-29 07:15:22,366 [myid:] - INFO [main:ClientCnxn@1653] - zookeeper.request.timeout value is 0. feature enabled=
Welcome to ZooKeeper!
JLine support is enabled
2019-08-29 07:15:22,563 [myid:localhost:2181] - INFO [main-SendThread(localhost:2181):ClientCnxn$SendThread@1112] - Opening socket connection to server localhost/0:0:0:0:0:0:0:1:2181. Will not attempt to authenticate using SASL (unknown error)
2019-08-29 07:15:23,443 [myid:localhost:2181] - INFO [main-SendThread(localhost:2181):ClientCnxn$SendThread@959] - Socket connection established, initiating session, client: /0:0:0:0:0:0:0:1:37198, server: localhost/0:0:0:0:0:0:0:1:2181
2019-08-29 07:15:23,520 [myid:localhost:2181] - INFO [main-SendThread(localhost:2181):ClientCnxn$SendThread@1394] - Session establishment complete on server localhost/0:0:0:0:0:0:0:1:2181, sessionid = 0x10001216d990000, negotiated timeout = 30000
 
WATCHER::
 
WatchedEvent state:SyncConnected type:None path:null
[zk:localhost:2181(CONNECTED) 0] ls /
[zookeeper]
[zk: localhost:2181(CONNECTED) 1] quit
 
WATCHER::
 
WatchedEvent state:Closed type:None path:null
2019-08-29 07:15:37,042 [myid:] - INFO [main:ZooKeeper@1422] - Session: 0x10001216d990000 closed
2019-08-29 07:15:37,043 [myid:] - INFO [main-EventThread:ClientCnxn$EventThread@524] - EventThread shut down for session: 0x10001216d990000
root@d5c6f857cd88:/apache-zookeeper-3.5.5-bin# exit
exit
[root@localhost admin]#

Access externally (192.168.192.128:2181)

Cluster

Environment: Single host machine (192.168.192.128), start three zookeeper containers.

There is a problem involved here, which is the communication between Docker containers. This is very important!

Docker has three network modes: bridge, host, and none. When you create a container, if you do not specify --network, the default is bridge.

bridge: Assign an IP to each container and connect the container to a docker0 virtual bridge to communicate with the host through the docker0 bridge. That is to say, in this mode, you cannot use the host IP + container mapping port to communicate between Docker containers.

host: The container does not virtualize its own network card and configure its own IP, but uses the IP and port of the host machine. In this way, communication between Docker containers can use the host IP + container mapping port

none: No network.

=====================================================

First create a directory locally:

[root@localhost admin]# mkdir /usr/local/zookeeper-cluster
[root@localhost admin]# mkdir /usr/local/zookeeper-cluster/node1
[root@localhost admin]# mkdir /usr/local/zookeeper-cluster/node2
[root@localhost admin]# mkdir /usr/local/zookeeper-cluster/node3
[root@localhost admin]# ll /usr/local/zookeeper-cluster/
total 0
drwxr-xr-x. 2 root root 6 Aug 28 23:02 node1
drwxr-xr-x. 2 root root 6 Aug 28 23:02 node2
drwxr-xr-x. 2 root root 6 Aug 28 23:02 node3

Then execute the command to start

docker run -d -p 2181:2181 -p 2888:2888 -p 3888:3888 --name zookeeper_node1 --privileged --restart always \
-v /usr/local/zookeeper-cluster/node1/volumes/data:/data \
-v /usr/local/zookeeper-cluster/node1/volumes/datalog:/datalog \
-v /usr/local/zookeeper-cluster/node1/volumes/logs:/logs \
-e ZOO_MY_ID=1 \
-e "ZOO_SERVERS=server.1=192.168.192.128:2888:3888;2181 server.2=192.168.192.128:2889:3889;2182 server.3=192.168.192.128:2890:3890;2183" 3487af26dee9

docker run -d -p 2182:2181 -p 2889:2888 -p 3889:3888 --name zookeeper_node2 --privileged --restart always \
-v /usr/local/zookeeper-cluster/node2/volumes/data:/data \
-v /usr/local/zookeeper-cluster/node2/volumes/datalog:/datalog \
-v /usr/local/zookeeper-cluster/node2/volumes/logs:/logs \
-e ZOO_MY_ID=2 \
-e "ZOO_SERVERS=server.1=192.168.192.128:2888:3888;2181 server.2=192.168.192.128:2889:3889;2182 server.3=192.168.192.128:2890:3890;2183" 3487af26dee9

docker run -d -p 2183:2181 -p 2890:2888 -p 3890:3888 --name zookeeper_node3 --privileged --restart always \
-v /usr/local/zookeeper-cluster/node3/volumes/data:/data \
-v /usr/local/zookeeper-cluster/node3/volumes/datalog:/datalog \
-v /usr/local/zookeeper-cluster/node3/volumes/logs:/logs \
-e ZOO_MY_ID=3 \
-e "ZOO_SERVERS=server.1=192.168.192.128:2888:3888;2181 server.2=192.168.192.128:2889:3889;2182 server.3=192.168.192.128:2890:3890;2183" 3487af26dee9

【pit】

At first glance, there is nothing wrong. First, map the port to the host machine, and then the access address between the three zookeepers is the host machine IP: mapped port. There is nothing wrong.

You can see the problem by looking at the network mode I mentioned earlier. There is a problem with the IP in ZOO_SERVERS. People who make this mistake do not understand the network mode of Docker. What is wrong? See below.

About ZOO_SERVERS

What does this mean? Starting from 3.5.0, the clientPort and clientPortAddress configuration parameters should no longer be used. Instead, this information is now part of the server keyword specification.

The port mappings of the three containers are different, such as 2181/2182/2183. Because it is a host machine, the ports cannot conflict. If you are not on the same machine, you do not need to modify the port.

The last parameter is the image ID, or it can be the image name: TAG.

The --privileged=true parameter is to solve [chown: changing ownership of '/data': Permission denied], you can also omit true

Execution Result:

[root@localhost admin]# docker run -d -p 2181:2181 -p 2888:2888 -p 3888:3888 --name zookeeper_node1 --privileged --restart always \
> -v /usr/local/zookeeper-cluster/node1/volumes/data:/data \
> -v /usr/local/zookeeper-cluster/node1/volumes/datalog:/datalog \
> -v /usr/local/zookeeper-cluster/node1/volumes/logs:/logs \
> -e ZOO_MY_ID=1 \
> -e "ZOO_SERVERS=server.1=192.168.192.128:2888:3888;2181 server.2=192.168.192.128:2889:3889;2182 server.3=192.168.192.128:2890:3890;2183" 3487af26dee9
4bfa6bbeb936037e178a577e5efbd06d4a963e91d67274413b933fd189917776
[root@localhost admin]# docker run -d -p 2182:2181 -p 2889:2888 -p 3889:3888 --name zookeeper_node2 --privileged --restart always \
> -v /usr/local/zookeeper-cluster/node2/volumes/data:/data \
> -v /usr/local/zookeeper-cluster/node2/volumes/datalog:/datalog \
> -v /usr/local/zookeeper-cluster/node2/volumes/logs:/logs \
> -e ZOO_MY_ID=2 \
> -e "ZOO_SERVERS=server.1=192.168.192.128:2888:3888;2181 server.2=192.168.192.128:2889:3889;2182 server.3=192.168.192.128:2890:3890;2183" 3487af26dee9
dbb7f1f323a09869d043152a4995e73bad5f615fd81bf11143fd1c28180f9869
[root@localhost admin]# docker run -d -p 2183:2181 -p 2890:2888 -p 3890:3888 --name zookeeper_node3 --privileged --restart always \
> -v /usr/local/zookeeper-cluster/node3/volumes/data:/data \
> -v /usr/local/zookeeper-cluster/node3/volumes/datalog:/datalog \
> -v /usr/local/zookeeper-cluster/node3/volumes/logs:/logs \
> -e ZOO_MY_ID=3 \
> -e "ZOO_SERVERS=server.1=192.168.192.128:2888:3888;2181 server.2=192.168.192.128:2889:3889;2182 server.3=192.168.192.128:2890:3890;2183" 3487af26dee9
6dabae1d92f0e861cc7515c014c293f80075c2762b254fc56312a6d3b450a919
[root@localhost admin]#

View the started container

[root@localhost admin]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
0:3890->3888/tcp zookeeper_node3 6dabae1d92f0 3487af26dee9 "/docker-entrypoin..." 31 seconds ago Up 29 seconds 8080/tcp, 0.0.0.0:2183->2181/tcp, 0.0.0.0:2890->2888/tcp, 0.0.0.0:3890->3888/tcp zookeeper_node3
dbb7f1f323a0 3487af26dee9 "/docker-entrypoint..." 36 seconds ago Up 35 seconds 8080/tcp, 0.0.0.0:2182->2181/tcp, 0.0.0.0:2889->2888/tcp, 0.0.0.0:3889->3888/tcp zookeeper_node2
4bfa6bbeb936 3487af26dee9 "/docker-entrypoin..." 46 seconds ago Up 45 seconds 0.0.0.0:2181->2181/tcp, 0.0.0.0:2888->2888/tcp, 0.0.0.0:3888->3888/tcp, 8080/tcp zookeeper_node1
[root@localhost admin]#

Isn't it said there is a mistake? How come it started successfully? ? Let's take a look at the startup log of node 1

[root@localhost admin]# docker logs -f 4bfa6bbeb936
ZooKeeper JMX enabled by default

...

2019-08-29 09:20:22,665 [myid:1] - WARN [WorkerSender[myid=1]:QuorumCnxManager@677] - Cannot open channel to 2 at election address /192.168.192.128:3889
java.net.ConnectException: Connection refused (Connection refused)
  at java.net.PlainSocketImpl.socketConnect(Native Method)
  at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
  at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
  at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
  at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
  at java.net.Socket.connect(Socket.java:589)
  at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:648)
  at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:705)
  at org.apache.zookeeper.server.quorum.QuorumCnxManager.toSend(QuorumCnxManager.java:618)
  at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.process(FastLeaderElection.java:477)
  at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.run(FastLeaderElection.java:456)
  at java.lang.Thread.run(Thread.java:748)
2019-08-29 09:20:22,666 [myid:1] - WARN [WorkerSender[myid=1]:QuorumCnxManager@677] - Cannot open channel to 3 at election address /192.168.192.128:3890
java.net.ConnectException: Connection refused (Connection refused)
  at java.net.PlainSocketImpl.socketConnect(Native Method)
  at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
  at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
  at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
  at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
  at java.net.Socket.connect(Socket.java:589)
  at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:648)
  at org.apache.zookeeper.server.quorum.QuorumCnxManager.connectOne(QuorumCnxManager.java:705)
  at org.apache.zookeeper.server.quorum.QuorumCnxManager.toSend(QuorumCnxManager.java:618)
  at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.process(FastLeaderElection.java:477)
  at org.apache.zookeeper.server.quorum.FastLeaderElection$Messenger$WorkerSender.run(FastLeaderElection.java:456)
  at java.lang.Thread.run(Thread.java:748)

Can't connect to 2 and 3. Why? Because in the default Docker network mode, the host machine's IP+mapped port cannot be found at all! They have their own IP! as follows:

[root@localhost admin]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
6dabae1d92f0 3487af26dee9 "/docker-entrypoin..." 5 minutes ago Up 5 minutes 8080/tcp, 0.0.0.0:2183->2181/tcp, 0.0.0.0:2890->2888/tcp, 0.0.0.0:3890->3888/tcp zookeeper_node3
dbb7f1f323a0 3487af26dee9 "/docker-entrypoin..." 6 minutes ago Up 6 minutes 8080/tcp, 0.0.0.0:2182->2181/tcp, 0.0.0.0:2889->2888/tcp, 0.0.0.0:3889->3888/tcp zookeeper_node2
4bfa6bbeb936 3487af26dee9 "/docker-entrypoin..." 6 minutes ago Up 6 minutes 0.0.0.0:2181->2181/tcp, 0.0.0.0:2888->2888/tcp, 0.0.0.0:3888->3888/tcp, 8080/tcp zookeeper_node1


[root@localhost admin]# docker inspect 4bfa6bbeb936
      "Networks": {
        "bridge": {
          "IPAMConfig": null,
          "Links": null,
          "Aliases": null,
          "NetworkID": "5fc1ce4362afe3d34fdf260ab0174c36fe4b7daf2189702eae48101a755079f3",
          "EndpointID": "368237e4c903cc663111f1fe33ac4626a9100fb5a22aec85f5eccbc6968a1631",
          "Gateway": "172.17.0.1",
          "IPAddress": "172.17.0.2",
          "IPPrefixLen": 16,
          "IPv6Gateway": "",
          "GlobalIPv6Address": "",
          "GlobalIPv6PrefixLen": 0,
          "MacAddress": "02:42:ac:11:00:02"
        }
      }
    }
  }
]

[root@localhost admin]# docker inspect dbb7f1f323a0
      "Networks": {
        "bridge": {
          "IPAMConfig": null,
          "Links": null,
          "Aliases": null,
          "NetworkID": "5fc1ce4362afe3d34fdf260ab0174c36fe4b7daf2189702eae48101a755079f3",
          "EndpointID": "8a9734044a566d5ddcd7cbbf6661abb2730742f7c73bd8733ede9ed8ef106659",
          "Gateway": "172.17.0.1",
          "IPAddress": "172.17.0.3",
          "IPPrefixLen": 16,
          "IPv6Gateway": "",
          "GlobalIPv6Address": "",
          "GlobalIPv6PrefixLen": 0,
          "MacAddress": "02:42:ac:11:00:03"
        }
      }
    }
  }
]

[root@localhost admin]# docker inspect 6dabae1d92f0
      "Networks": {
        "bridge": {
          "IPAMConfig": null,
          "Links": null,
          "Aliases": null,
          "NetworkID": "5fc1ce4362afe3d34fdf260ab0174c36fe4b7daf2189702eae48101a755079f3",
          "EndpointID": "b10329b9940a07aacb016d8d136511ec388de02bf3bd0e0b50f7f4cbb7f138ec",
          "Gateway": "172.17.0.1",
          "IPAddress": "172.17.0.4",
          "IPPrefixLen": 16,
          "IPv6Gateway": "",
          "GlobalIPv6Address": "",
          "GlobalIPv6PrefixLen": 0,
          "MacAddress": "02:42:ac:11:00:04"
        }
      }
    }
  }
]

node1---172.17.0.2
node2---172.17.0.3
node3---172.17.0.4

Now that we know it has its own IP, another problem arises, that is, its IP is dynamic and we cannot know it before starting. One solution is to create your own bridge network and then specify the IP when creating the container.

[Start the right way]

[root@localhost admin]# docker network create --driver bridge --subnet=172.18.0.0/16 --gateway=172.18.0.1 zoonet
8257c501652a214d27efdf5ef71ff38bfe222c3a2a7898be24b8df9db1fb3b13
[root@localhost admin]# docker network ls
NETWORK ID NAME DRIVER SCOPE
5fc1ce4362af bridge bridge local
6aa33e21444e host host local
20e563b93ce9 none null local
8257c501652a zoonet bridge local
[root@localhost admin]# docker network inspect 8257c501652a
[
  {
    "Name": "zoonet",
    "Id": "8257c501652a214d27efdf5ef71ff38bfe222c3a2a7898be24b8df9db1fb3b13",
    "Created": "2019-08-29T06:08:01.442601483-04:00",
    "Scope": "local",
    "Driver": "bridge",
    "EnableIPv6": false,
    "IPAM": {
      "Driver": "default",
      "Options": {},
      "Config": [
        {
          "Subnet": "172.18.0.0/16",
          "Gateway": "172.18.0.1"
        }
      ]
    },
    "Internal": false,
    "Attachable": false,
    "Containers": {},
    "Options": {},
    "Labels": {}
  }
]

Then we modify the creation command of the zookeeper container.

docker run -d -p 2181:2181 --name zookeeper_node1 --privileged --restart always --network zoonet --ip 172.18.0.2 \
-v /usr/local/zookeeper-cluster/node1/volumes/data:/data \
-v /usr/local/zookeeper-cluster/node1/volumes/datalog:/datalog \
-v /usr/local/zookeeper-cluster/node1/volumes/logs:/logs \
-e ZOO_MY_ID=1 \
-e "ZOO_SERVERS=server.1=172.18.0.2:2888:3888;2181 server.2=172.18.0.3:2888:3888;2181 server.3=172.18.0.4:2888:3888;2181" 3487af26dee9

docker run -d -p 2182:2181 --name zookeeper_node2 --privileged --restart always --network zoonet --ip 172.18.0.3 \
-v /usr/local/zookeeper-cluster/node2/volumes/data:/data \
-v /usr/local/zookeeper-cluster/node2/volumes/datalog:/datalog \
-v /usr/local/zookeeper-cluster/node2/volumes/logs:/logs \
-e ZOO_MY_ID=2 \
-e "ZOO_SERVERS=server.1=172.18.0.2:2888:3888;2181 server.2=172.18.0.3:2888:3888;2181 server.3=172.18.0.4:2888:3888;2181" 3487af26dee9

docker run -d -p 2183:2181 --name zookeeper_node3 --privileged --restart always --network zoonet --ip 172.18.0.4 \
-v /usr/local/zookeeper-cluster/node3/volumes/data:/data \
-v /usr/local/zookeeper-cluster/node3/volumes/datalog:/datalog \
-v /usr/local/zookeeper-cluster/node3/volumes/logs:/logs \
-e ZOO_MY_ID=3 \
-e "ZOO_SERVERS=server.1=172.18.0.2:2888:3888;2181 server.2=172.18.0.3:2888:3888;2181 server.3=172.18.0.4:2888:3888;2181" 3487af26dee9

1. Since 2888 and 3888 do not need to be exposed, they are not mapped;

2. Specify your own network and IP;

3. The environment between each container is isolated, so the ports used in the container are the same: 2181/2888/3888

Running results:

[root@localhost admin]# docker run -d -p 2181:2181 --name zookeeper_node1 --privileged --restart always --network zoonet --ip 172.18.0.2 \
> -v /usr/local/zookeeper-cluster/node1/volumes/data:/data \
> -v /usr/local/zookeeper-cluster/node1/volumes/datalog:/datalog \
> -v /usr/local/zookeeper-cluster/node1/volumes/logs:/logs \
> -e ZOO_MY_ID=1 \
> -e "ZOO_SERVERS=server.1=172.18.0.2:2888:3888;2181 server.2=172.18.0.3:2888:3888;2181 server.3=172.18.0.4:2888:3888;2181" 3487af26dee9
50c07cf11fab2d3b4da6d8ce48d8ed4a7beaab7d51dd542b8309f781e9920c36
[root@localhost admin]# docker run -d -p 2182:2181 --name zookeeper_node2 --privileged --restart always --network zoonet --ip 172.18.0.3 \
> -v /usr/local/zookeeper-cluster/node2/volumes/data:/data \
> -v /usr/local/zookeeper-cluster/node2/volumes/datalog:/datalog \
> -v /usr/local/zookeeper-cluster/node2/volumes/logs:/logs \
> -e ZOO_MY_ID=2 \
> -e "ZOO_SERVERS=server.1=172.18.0.2:2888:3888;2181 server.2=172.18.0.3:2888:3888;2181 server.3=172.18.0.4:2888:3888;2181" 3487af26dee9
649a4dbfb694504acfe4b8e11b990877964477bb41f8a230bd191cba7d20996f
[root@localhost admin]# docker run -d -p 2183:2181 --name zookeeper_node3 --privileged --restart always --network zoonet --ip 172.18.0.4 \
> -v /usr/local/zookeeper-cluster/node3/volumes/data:/data \
> -v /usr/local/zookeeper-cluster/node3/volumes/datalog:/datalog \
> -v /usr/local/zookeeper-cluster/node3/volumes/logs:/logs \
> -e ZOO_MY_ID=3 \
> -e "ZOO_SERVERS=server.1=172.18.0.2:2888:3888;2181 server.2=172.18.0.3:2888:3888;2181 server.3=172.18.0.4:2888:3888;2181" 3487af26dee9
c8bc1b9ae9adf86e9c7f6a3264f883206c6d0e4f6093db3200de80ef39f57160
[root@localhost admin]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
c8bc1b9ae9ad 3487af26dee9 "/docker-entrypoin..." 17 seconds ago Up 16 seconds 2888/tcp, 3888/tcp, 8080/tcp, 0.0.0.0:2183->2181/tcp zookeeper_node3
649a4dbfb694 3487af26dee9 "/docker-entrypoint..." 22 seconds ago Up 21 seconds 2888/tcp, 3888/tcp, 8080/tcp, 0.0.0.0:2182->2181/tcp zookeeper_node2
50c07cf11fab 3487af26dee9 "/docker-entrypoint..." 33 seconds ago Up 32 seconds 2888/tcp, 3888/tcp, 0.0.0.0:2181->2181/tcp, 8080/tcp zookeeper_node1
[root@localhost admin]#

Enter the container to verify:

[root@localhost admin]# docker exec -it 50c07cf11fab bash
root@50c07cf11fab:/apache-zookeeper-3.5.5-bin# ./bin/zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /conf/zoo.cfg
Client port found: 2181. Client address: localhost.
Mode: follower
root@50c07cf11fab:/apache-zookeeper-3.5.5-bin# exit
exit
[root@localhost admin]# docker exec -it 649a4dbfb694 bash
root@649a4dbfb694:/apache-zookeeper-3.5.5-bin# ./bin/zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /conf/zoo.cfg
Client port found: 2181. Client address: localhost.
Mode: leader
root@649a4dbfb694:/apache-zookeeper-3.5.5-bin# exit
exit
[root@localhost admin]# docker exec -it c8bc1b9ae9ad bash
root@c8bc1b9ae9ad:/apache-zookeeper-3.5.5-bin# ./bin/zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /conf/zoo.cfg
Client port found: 2181. Client address: localhost.
Mode: follower
root@c8bc1b9ae9ad:/apache-zookeeper-3.5.5-bin# exit
exit
[root@localhost admin]#

Verify the creation of the node

Open the firewall for external access

firewall-cmd --zone=public --add-port=2181/tcp --permanent
firewall-cmd --zone=public --add-port=2182/tcp --permanent
firewall-cmd --zone=public --add-port=2183/tcp --permanent
systemctl restart firewalld
firewall-cmd --list-all

Locally, I use the zookeeper client to connect to the cluster on the virtual machine:

You can see that the connection is successful!

Cluster installation method 2: installation via docker stack deploy or docker-compose

Use docker-compose here. Install docker-compose first

[root@localhost admin]# curl -L "https://github.com/docker/compose/releases/download/1.24.1/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
 % Total % Received % Xferd Average Speed ​​Time Time Time Current
                 Dload Upload Total Spent Left Speed
100 617 0 617 0 0 145 0 --:--:-- 0:00:04 --:--:-- 145
100 15.4M 100 15.4M 0 0 131k 0 0:02:00 0:02:00 --:--:-- 136k
[root@localhost admin]# chmod +x /usr/local/bin/docker-compose

Check the version (to verify whether the installation is successful)

[root@localhost admin]# docker-compose --version
docker-compose version 1.24.1, build 4667896b

If you uninstall

rm /usr/local/bin/docker-compose

Start configuration and create three new mount directories

[root@localhost admin]# mkdir /usr/local/zookeeper-cluster/node4
[root@localhost admin]# mkdir /usr/local/zookeeper-cluster/node5
[root@localhost admin]# mkdir /usr/local/zookeeper-cluster/node6

Create a new directory and create a new file in it

[root@localhost admin]# mkdir DockerComposeFolder
[root@localhost admin]# cd DockerComposeFolder/
[root@localhost DockerComposeFolder]# vim docker-compose.yml

The file contents are as follows: (see above for custom network)

version: '3.1'

services:
 zoo1:
  image: zookeeper
  restart: always
  privileged: true
  hostname: zoo1
  ports:
   - 2181:2181
  volumes: #Mount data - /usr/local/zookeeper-cluster/node4/data:/data
   - /usr/local/zookeeper-cluster/node4/datalog:/datalog
  environment:
   ZOO_MY_ID: 4
   ZOO_SERVERS: server.4=0.0.0.0:2888:3888;2181 server.5=zoo2:2888:3888;2181 server.6=zoo3:2888:3888;2181
  networks:
   default:
    ipv4_address: 172.18.0.14

 zoo2:
  image: zookeeper
  restart: always
  privileged: true
  hostname: zoo2
  ports:
   - 2182:2181
  volumes: #Mount data - /usr/local/zookeeper-cluster/node5/data:/data
   - /usr/local/zookeeper-cluster/node5/datalog:/datalog
  environment:
   ZOO_MY_ID: 5
   ZOO_SERVERS: server.4=zoo1:2888:3888;2181 server.5=0.0.0.0:2888:3888;2181 server.6=zoo3:2888:3888;2181
  networks:
   default:
    ipv4_address: 172.18.0.15

 zoo3:
  image: zookeeper
  restart: always
  privileged: true
  hostname: zoo3
  ports:
   - 2183:2181
  volumes: #Mount data - /usr/local/zookeeper-cluster/node6/data:/data
   - /usr/local/zookeeper-cluster/node6/datalog:/datalog
  environment:
   ZOO_MY_ID: 6
   ZOO_SERVERS: server.4=zoo1:2888:3888;2181 server.5=zoo2:2888:3888;2181 server.6=0.0.0.0:2888:3888;2181
  networks:
   default:
    ipv4_address: 172.18.0.16

networks: # Custom network default:
  external:
   name: zoonet

Note that there can be no tabs in the YAML file, only spaces.

The relationship between version and Docker version is as follows:

Then execute (-d background start)

docker-compose -f docker-compose.yml up -d

View started containers

[root@localhost DockerComposeFolder]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
a2c14814037d zookeeper "/docker-entrypoin..." 6 minutes ago Up About a minute 2888/tcp, 3888/tcp, 8080/tcp, 0.0.0.0:2183->2181/tcp dockercomposefolder_zoo3_1
50310229b216 zookeeper "/docker-entrypoin..." 6 minutes ago Up About a minute 2888/tcp, 3888/tcp, 0.0.0.0:2181->2181/tcp, 8080/tcp dockercomposefolder_zoo1_1
475d8a9e2d08 zookeeper "/docker-entrypoin..." 6 minutes ago Up About a minute 2888/tcp, 3888/tcp, 8080/tcp, 0.0.0.0:2182->2181/tcp dockercomposefolder_zoo2_1

Entering a container

[root@localhost DockerComposeFolder]# docker exec -it a2c14814037d bash
root@zoo3:/apache-zookeeper-3.5.5-bin# ./bin/zkCli.sh
Connecting to localhost:2181

....

WatchedEvent state:SyncConnected type:None path:null
[zk:localhost:2181(CONNECTED) 0] 
[zk:localhost:2181(CONNECTED) 1] ls /
[zookeeper]
[zk: localhost:2181(CONNECTED) 2] create /hi
Created /hi
[zk: localhost:2181(CONNECTED) 3] ls /
[hi, zookeeper]

Enter another container

[root@localhost DockerComposeFolder]# docker exec -it 50310229b216 bash
root@zoo1:/apache-zookeeper-3.5.5-bin# ./bin/zkCli.sh
Connecting to localhost:2181

...

WatchedEvent state:SyncConnected type:None path:null

[zk:localhost:2181(CONNECTED) 0] ls /
[hi, zookeeper]

Local client connects to the cluster:

zkCli.cmd -server 192.168.192.128:2181,192.168.192.128:2182,192.168.192.128:2183

Check

Stop all active containers

Remove all stopped containers

More docker-compose commands:

[root@localhost DockerComposeFolder]# docker-compose --help
Define and run multi-container applications with Docker.

Usage:
 docker-compose [-f <arg>...] [options] [COMMAND] [ARGS...]
 docker-compose -h|--help

Options:
 -f, --file FILE Specify an alternate compose file
               (default: docker-compose.yml)
 -p, --project-name NAME Specify an alternate project name
               (default: directory name)
 --verbose Show more output
 --log-level LEVEL Set log level (DEBUG, INFO, WARNING, ERROR, CRITICAL)
 --no-ansi Do not print ANSI control characters
 -v, --version Print version and exit
 -H, --host HOST Daemon socket to connect to

 --tls Use TLS; implied by --tlsverify
 --tlscacert CA_PATH Trust certs signed only by this CA
 --tlscert CLIENT_CERT_PATH Path to TLS certificate file
 --tlskey TLS_KEY_PATH Path to TLS key file
 --tlsverify Use TLS and verify the remote
 --skip-hostname-check Don't check the daemon's hostname against the
               name specified in the client certificate
 --project-directory PATH Specify an alternate working directory
               (default: the path of the Compose file)
 --compatibility If set, Compose will attempt to convert keys
               in v3 files to their non-Swarm equivalent

Commands:
 build Build or rebuild services
 bundle Generate a Docker bundle from the Compose file
 config Validate and view the Compose file
 create Create services
 down Stop and remove containers, networks, images, and volumes
 events Receive real time events from containers
 exec Execute a command in a running container
 help Get help on a command
 images List images
 kill Kill containers
 logs View output from containers
 pause Pause services
 port Print the public port for a port binding
 ps List containers
 pull Pull service images
 push service images
 restart Restart services
 rm Remove stopped containers
 run Run a one-off command
 scale Set number of containers for a service
 start Start services
 stop Stop services
 top Display the running processes
 unpause Unpause services
 up Create and start containers
 version Show the Docker-Compose version information

This is the end of this article about installing ZooKeeper (stand-alone and cluster) under Docker. For more information about installing ZooKeeper on Docker, please search for previous articles on 123WORDPRESS.COM or continue to browse the following related articles. I hope you will support 123WORDPRESS.COM in the future!

You may also be interested in:
  • Implementation of Docker to build Zookeeper&Kafka cluster
  • How to build a Zookeeper cluster with docker

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