When using docker images from registries, I often need to see the volumes created by the image's containers.
Note: I'm using docker version 1.3.2 on Red Hat 7.
The postgres official image from the Docker Registry has a volume configured for containers at /var/lib/postgresql/data.
What's the most succinct command to show the volume at /var/lib/postgresql/data in a postgres container?
Use docker ps to get the container id.
Then use that container id in the docker inspect command to find the mounts for that container:
docker inspect -f '{{ .Mounts }}' containerid
Example:
terminal 1
docker run -it -v /tmp:/tmp ubuntu:14.04 /bin/bash
terminal 2
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
ddb7b55902cc ubuntu:14.04 "/bin/bash" About a minute ago Up About a minute distracted_banach
$ docker inspect -f "{{ .Mounts }}" ddb7
map[/tmp:/tmp]
The output
map[/tmp:/tmp]
is, apparently, due to the use of the Go language to implement the docker command tools.
The docker inspect command without the -f format is quite verbose. Since it is JSON you could pipe it to python or nodejs and extract whatever you needed.
paul@home:~$ docker inspect ddb7
[{
"AppArmorProfile": "",
"Args": [],
"Config": {
"AttachStderr": true,
"AttachStdin": true,
"AttachStdout": true,
"Cmd": [
"/bin/bash"
],
"CpuShares": 0,
"Cpuset": "",
"Domainname": "",
"Entrypoint": null,
"Env": [
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
],
"ExposedPorts": null,
"Hostname": "ddb7b55902cc",
"Image": "ubuntu:14.04",
"MacAddress": "",
"Memory": 0,
"MemorySwap": 0,
"NetworkDisabled": false,
"OnBuild": null,
"OpenStdin": true,
"PortSpecs": null,
"StdinOnce": true,
"Tty": true,
"User": "",
"Volumes": null,
"WorkingDir": ""
},
"Created": "2015-05-08T22:41:44.74862921Z",
"Driver": "devicemapper",
"ExecDriver": "native-0.2",
"ExecIDs": null,
"HostConfig": {
"Binds": [
"/tmp:/tmp"
],
"CapAdd": null,
"CapDrop": null,
"ContainerIDFile": "",
"Devices": [],
"Dns": null,
"DnsSearch": null,
"ExtraHosts": null,
"IpcMode": "",
"Links": null,
"LxcConf": [],
"NetworkMode": "bridge",
"PidMode": "",
"PortBindings": {},
"Privileged": false,
"PublishAllPorts": false,
"ReadonlyRootfs": false,
"RestartPolicy": {
"MaximumRetryCount": 0,
"Name": ""
},
"SecurityOpt": null,
"VolumesFrom": null
},
"HostnamePath": "/var/lib/docker/containers/ddb7b55902cc328612d794570fe9a936d96a9644411e89c4ea116a5fef4c311a/hostname",
"HostsPath": "/var/lib/docker/containers/ddb7b55902cc328612d794570fe9a936d96a9644411e89c4ea116a5fef4c311a/hosts",
"Id": "ddb7b55902cc328612d794570fe9a936d96a9644411e89c4ea116a5fef4c311a",
"Image": "ed5a78b7b42bde1e3e4c2996e02da778882dca78f8919cbd0deb6694803edec3",
"MountLabel": "",
"Name": "/distracted_banach",
"NetworkSettings": {
"Bridge": "docker0",
"Gateway": "172.17.42.1",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "172.17.0.4",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"LinkLocalIPv6Address": "fe80::42:acff:fe11:4",
"LinkLocalIPv6PrefixLen": 64,
"MacAddress": "02:42:ac:11:00:04",
"PortMapping": null,
"Ports": {}
},
"Path": "/bin/bash",
"ProcessLabel": "",
"ResolvConfPath": "/var/lib/docker/containers/ddb7b55902cc328612d794570fe9a936d96a9644411e89c4ea116a5fef4c311a/resolv.conf",
"RestartCount": 0,
"State": {
"Error": "",
"ExitCode": 0,
"FinishedAt": "0001-01-01T00:00:00Z",
"OOMKilled": false,
"Paused": false,
"Pid": 6115,
"Restarting": false,
"Running": true,
"StartedAt": "2015-05-08T22:41:45.367432585Z"
},
"Volumes": {
"/tmp": "/tmp"
},
"VolumesRW": {
"/tmp": true
}
}
]
docker history <image name> will show the layers baked into an image. Unfortunately, docker history seems hobbled by its formatting and lack of options to choose what is displayed.
You can choose terse and verbose formats, via the --no-trunc flag.
$ docker history drpaulbrewer/spark-worker
IMAGE CREATED CREATED BY SIZE
438ff4e1753a 2 weeks ago /bin/sh -c #(nop) CMD [/bin/sh -c /spark/my-s 0 B
6b664e299724 2 weeks ago /bin/sh -c #(nop) ADD file:09da603c5f0dca7cc6 296 B
f6ae126ae124 2 weeks ago /bin/sh -c #(nop) MAINTAINER drpaulbrewer@eaf 0 B
70bcb3ffaec9 2 weeks ago /bin/sh -c #(nop) EXPOSE 2222/tcp 4040/tcp 60 0 B
1332ac203849 2 weeks ago /bin/sh -c apt-get update && apt-get --yes up 1.481 GB
8e6f1e0bb1b0 2 weeks ago /bin/sh -c sed -e 's/archive.ubuntu.com/www.g 1.975 kB
b3d242776b1f 2 weeks ago /bin/sh -c #(nop) WORKDIR /spark/spark-1.3.1 0 B
ac0d6cc5aa3f 2 weeks ago /bin/sh -c #(nop) ADD file:b6549e3d28e2d149c0 25.89 MB
6ee404a44b3f 5 weeks ago /bin/sh -c #(nop) WORKDIR /spark 0 B
c167faff18cf 5 weeks ago /bin/sh -c adduser --disabled-password --home 335.1 kB
f55d468318a4 5 weeks ago /bin/sh -c #(nop) MAINTAINER drpaulbrewer@eaf 0 B
19c8c047d0fe 8 weeks ago /bin/sh -c #(nop) CMD [/bin/bash] 0 B
c44d976a473f 8 weeks ago /bin/sh -c sed -i 's/^#\s*\(deb.*universe\)$/ 1.879 kB
14dbf1d35e28 8 weeks ago /bin/sh -c echo '#!/bin/sh' > /usr/sbin/polic 701 B
afa7a164a0d2 8 weeks ago /bin/sh -c #(nop) ADD file:57f97478006b988c0c 131.5 MB
511136ea3c5a 23 months ago 0 B
Here's a verbose example.
$ docker history --no-trunc=true drpaulbrewer/spark-worker
IMAGE CREATED CREATED BY SIZE
438ff4e1753a60779f389a3de593d41f7d24a61da6e1df76dded74a688febd64 2 weeks ago /bin/sh -c #(nop) CMD [/bin/sh -c /spark/my-spark-worker.sh] 0 B
6b664e29972481b8d6d47f98167f110609d9599f48001c3ca11c22364196c98a 2 weeks ago /bin/sh -c #(nop) ADD file:09da603c5f0dca7cc60f1911caf30c3c70df5e4783f7eb10468e70df66e2109f in /spark/ 296 B
f6ae126ae124ca211c04a1257510930b37ea78425e31a273ea0b1495fa176c57 2 weeks ago /bin/sh -c #(nop) MAINTAINER drpaulbrewer@eaftc.com 0 B
70bcb3ffaec97a0d14e93b170ed70cc7d68c3c9dfb0222c1d360a300d6e05255 2 weeks ago /bin/sh -c #(nop) EXPOSE 2222/tcp 4040/tcp 6066/tcp 7077/tcp 7777/tcp 8080/tcp 8081/tcp 0 B
1332ac20384947fe1f15107213b675e5be36a68d72f0e81153d6d5a21acf35af 2 weeks ago /bin/sh -c apt-get update && apt-get --yes upgrade && apt-get --yes install sed nano curl wget openjdk-8-jdk scala && echo "JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64" >>/etc/environment && export MAVEN_OPTS="-Xmx2g -XX:MaxPermSize=512M -XX:ReservedCodeCacheSize=512m" && ./build/mvn -Phive -Phive-thriftserver -DskipTests clean package && chown -R spark:spark /spark && mkdir /var/run/sshd 1.481 GB
8e6f1e0bb1b0b9286947d3a4b443cc8099b00f9670aab1d58654051e06f62e51 2 weeks ago /bin/sh -c sed -e 's/archive.ubuntu.com/www.gtlib.gatech.edu\/pub/' /etc/apt/sources.list > /tmp/sources.list && mv /tmp/sources.list /etc/apt/sources.list 1.975 kB
b3d242776b1f1f1ae5685471d06a91a68f92845ef6fc6445d831835cd55e5d0b 2 weeks ago /bin/sh -c #(nop) WORKDIR /spark/spark-1.3.1 0 B
ac0d6cc5aa3fdc3b65fc0173f6775af283c3c395c8dae945cf23940435f2785d 2 weeks ago /bin/sh -c #(nop) ADD file:b6549e3d28e2d149c0bc84f69eb0beab16f62780fc4889bcc64cfc9ce9f762d6 in /spark/ 25.89 MB
6ee404a44b3fdd3ef3318dc10f3d002f1995eea238c78f4eeb9733d00bb29404 5 weeks ago /bin/sh -c #(nop) WORKDIR /spark 0 B
c167faff18cfecedef30343ef1cb54aca45f4ef0478a3f6296746683f69d601b 5 weeks ago /bin/sh -c adduser --disabled-password --home /spark spark 335.1 kB
f55d468318a4778733160d377c5d350dc8f593683009699c2af85244471b15a3 5 weeks ago /bin/sh -c #(nop) MAINTAINER drpaulbrewer@eaftc.com 0 B
19c8c047d0fe2de7239120f2b5c1a20bbbcb4d3eb9cbf0efa59ab27ab047377a 8 weeks ago /bin/sh -c #(nop) CMD [/bin/bash] 0 B
c44d976a473f143937ef91449c73f2cabd109b540f6edf54facb9bc2b4fff136 8 weeks ago /bin/sh -c sed -i 's/^#\s*\(deb.*universe\)$/\1/g' /etc/apt/sources.list 1.879 kB
14dbf1d35e2849a00c6c2628055030fa84b4fb55eaadbe0ecad8b82df65cc0db 8 weeks ago /bin/sh -c echo '#!/bin/sh' > /usr/sbin/policy-rc.d && echo 'exit 101' >> /usr/sbin/policy-rc.d && chmod +x /usr/sbin/policy-rc.d && dpkg-divert --local --rename --add /sbin/initctl && cp -a /usr/sbin/policy-rc.d /sbin/initctl && sed -i 's/^exit.*/exit 0/' /sbin/initctl && echo 'force-unsafe-io' > /etc/dpkg/dpkg.cfg.d/docker-apt-speedup && echo 'DPkg::Post-Invoke { "rm -f /var/cache/apt/archives/*.deb /var/cache/apt/archives/partial/*.deb /var/cache/apt/*.bin || true"; };' > /etc/apt/apt.conf.d/docker-clean && echo 'APT::Update::Post-Invoke { "rm -f /var/cache/apt/archives/*.deb /var/cache/apt/archives/partial/*.deb /var/cache/apt/*.bin || true"; };' >> /etc/apt/apt.conf.d/docker-clean && echo 'Dir::Cache::pkgcache ""; Dir::Cache::srcpkgcache "";' >> /etc/apt/apt.conf.d/docker-clean && echo 'Acquire::Languages "none";' > /etc/apt/apt.conf.d/docker-no-languages && echo 'Acquire::GzipIndexes "true"; Acquire::CompressionTypes::Order:: "gz";' > /etc/apt/apt.conf.d/docker-gzip-indexes 701 B
afa7a164a0d215dbf45cd1aadad2a4d12b8e33fc890064568cc2ea6d42ef9b3c 8 weeks ago /bin/sh -c #(nop) ADD file:57f97478006b988c0c68e5bf82684372e427fd45f21cd7baf5d974d2cfb29e65 in / 131.5 MB
511136ea3c5a64f264b78b5433614aec563103b4d4702f3ba7d4d2698e22c158 23 months ago 0 B