查看Docker容器的信息的方法实现

目录创建tomcat容器第一种：进入容器内部获取信息第二种：执行docker exec命令第三种：使用docker inspect命令

对于运行在Docker环境的容器，有时我们想查询它们的一些基本信息，例如环境变量、hostname、ip地址等，接下来我们以一个tomcat容器为例，看看有哪些方式来取得这些信息；

创建tomcat容器

在docker环境下执行如下命令，即可创建一个名为tomcat001的tomcat容器：

docker run –name tomcat001 -idt tomcat

执行docker ps检查一下，容器创建成功：

root@maven:~# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 98d119ed4c73 tomcat “catalina.sh run” 10 minutes ago Up 10 minutes 8080/tcp tomcat001

获取信息常用的方式有如下三种：

进入容器内部获取信息；执行docker exec命令；执行docker inspect -f命令（推荐方式）；

第一种：进入容器内部获取信息

执行以下命令可进入容器内部：

docker exec -it tomcat001 /bin/bash

此时已进入容器内部，所以分别执行hostname、ip addr、env这三个命令可以获取相关信息，如下：

root@98d119ed4c73:/usr/local/tomcat# hostname 98d119ed4c73 root@98d119ed4c73:/usr/local/tomcat# ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 17: eth0@if18: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default link/ether 02:42:ac:11:00:05 brd ff:ff:ff:ff:ff:ff link-netnsid 0 inet 172.17.0.5/16 scope global eth0 valid_lft forever preferred_lft forever inet6 fe80::42:acff:fe11:5/64 scope link valid_lft forever preferred_lft forever root@98d119ed4c73:/usr/local/tomcat# env LD_LIBRARY_PATH=/usr/local/tomcat/native-jni-lib CATALINA_HOME=/usr/local/tomcat LANG=C.UTF-8 HOSTNAME=98d119ed4c73 OPENSSL_VERSION=1.1.0f-3+deb9u1 TOMCAT_VERSION=8.5.24 GPG_KEYS=05AB33110949707C93A279E3D3EFE6B686867BA6 07E48665A34DCAFAE522E5E6266191C37C037D42 47309207D818FFD8DCD3F83F1931D684307A10A5 541FBE7D8F78B25E055DDEE13C370389288584E7 61B832AC2F1C5A90F0F9B00A1C506407564C17A3 713DA88BE50911535FE716F5208B0AB1D63011C7 79F7026C690BAA50B92CD8B66A3AD3F4F22C4FED 9BA44C2621385CB966EBA586F72C284D731FABEE A27677289986DB50844682F8ACB77FC2E86E29AC A9C5DF4D22E99998D9875A5110C01C5A2F6059E7 DCFD35E0BF8CA7344752DE8B6FB21E8933C60243 F3A04C595DB5B6A5F1ECA43E3B7BBB100D811BBE F7DA48BB64BCB84ECBA7EE6935CD23C10D498E23 JAVA_HOME=/docker-java-home/jre TOMCAT_NATIVE_LIBDIR=/usr/local/tomcat/native-jni-lib JAVA_VERSION=8u151 PWD=/usr/local/tomcat HOME=/root CA_CERTIFICATES_JAVA_VERSION=20170531+nmu1 TOMCAT_MAJOR=8 JAVA_DEBIAN_VERSION=8u151-b12-1~deb9u1 TOMCAT_SHA1=9e26ba61c5665aafc849073edeb769be555283cd TERM=xterm SHLVL=1 TOMCAT_ASC_URLS=https://www.apache.org/dyn/closer.cgi?action=download&filename=tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc https://www-us.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc https://www.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc https://archive.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc PATH=/usr/local/tomcat/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin TOMCAT_TGZ_URLS=https://www.apache.org/dyn/closer.cgi?action=download&filename=tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz https://www-us.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz https://www.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz https://archive.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz _=/usr/bin/env

第二种：执行docker exec命令

不用进入容器，直接在docker环境执行docker exec 容器名 容器内命令的方式也可以获取相关信息，举例如下：

获取容器的hostname：docker exec tomcat001 hostname获取容器ip地址：docker exec tomcat001 ip addr获取容器环境变量：docker exec tomcat001 env

执行结果如下所示:

root@maven:~# docker exec tomcat001 hostname 98d119ed4c73 root@maven:~# docker exec tomcat001 ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 17: eth0@if18: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default link/ether 02:42:ac:11:00:05 brd ff:ff:ff:ff:ff:ff link-netnsid 0 inet 172.17.0.5/16 scope global eth0 valid_lft forever preferred_lft forever inet6 fe80::42:acff:fe11:5/64 scope link valid_lft forever preferred_lft forever root@maven:~# docker exec tomcat001 env PATH=/usr/local/tomcat/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin HOSTNAME=98d119ed4c73 LANG=C.UTF-8 JAVA_HOME=/docker-java-home/jre JAVA_VERSION=8u151 JAVA_DEBIAN_VERSION=8u151-b12-1~deb9u1 CA_CERTIFICATES_JAVA_VERSION=20170531+nmu1 CATALINA_HOME=/usr/local/tomcat TOMCAT_NATIVE_LIBDIR=/usr/local/tomcat/native-jni-lib LD_LIBRARY_PATH=/usr/local/tomcat/native-jni-lib OPENSSL_VERSION=1.1.0f-3+deb9u1 GPG_KEYS=05AB33110949707C93A279E3D3EFE6B686867BA6 07E48665A34DCAFAE522E5E6266191C37C037D42 47309207D818FFD8DCD3F83F1931D684307A10A5 541FBE7D8F78B25E055DDEE13C370389288584E7 61B832AC2F1C5A90F0F9B00A1C506407564C17A3 713DA88BE50911535FE716F5208B0AB1D63011C7 79F7026C690BAA50B92CD8B66A3AD3F4F22C4FED 9BA44C2621385CB966EBA586F72C284D731FABEE A27677289986DB50844682F8ACB77FC2E86E29AC A9C5DF4D22E99998D9875A5110C01C5A2F6059E7 DCFD35E0BF8CA7344752DE8B6FB21E8933C60243 F3A04C595DB5B6A5F1ECA43E3B7BBB100D811BBE F7DA48BB64BCB84ECBA7EE6935CD23C10D498E23 TOMCAT_MAJOR=8 TOMCAT_VERSION=8.5.24 TOMCAT_SHA1=9e26ba61c5665aafc849073edeb769be555283cd TOMCAT_TGZ_URLS=https://www.apache.org/dyn/closer.cgi?action=download&filename=tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz https://www-us.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz https://www.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz https://archive.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz TOMCAT_ASC_URLS=https://www.apache.org/dyn/closer.cgi?action=download&filename=tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc https://www-us.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc https://www.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc https://archive.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc HOME=/root

第三种：使用docker inspect命令

推荐使用docker inspect来获取信息，这个命令会返回一个json字符串，里面以key-value的格式准备了该容器相关的信息，内容十分丰富，可以一次性取得全部内容，也可以返回指定key对应的信息；

我们先来看看所有内容，执行命令docker inspect tomcat001，可以看到如下信息：

root@maven:~# docker inspect tomcat001 [ { “Id”: “98d119ed4c73c750e53353e77f7c6942803809a9d5dedc28d8b0f41ce58b8b17”, “Created”: “2018-05-06T07:39:45.464492435Z”, “Path”: “catalina.sh”, “Args”: [ “run” ], “State”: { “Status”: “running”, “Running”: true, “Paused”: false, “Restarting”: false, “OOMKilled”: false, “Dead”: false, “Pid”: 22468, “ExitCode”: 0, “Error”: “”, “StartedAt”: “2018-05-06T07:39:46.143092505Z”, “FinishedAt”: “0001-01-01T00:00:00Z” }, “Image”: “sha256:3dcfe809147daf54fbdbe1f6886b4c49df63f28e2b3c8ac119fef6a7f7490d3c”, “ResolvConfPath”: “/var/lib/docker/containers/98d119ed4c73c750e53353e77f7c6942803809a9d5dedc28d8b0f41ce58b8b17/resolv.conf”, “HostnamePath”: “/var/lib/docker/containers/98d119ed4c73c750e53353e77f7c6942803809a9d5dedc28d8b0f41ce58b8b17/hostname”, “HostsPath”: “/var/lib/docker/containers/98d119ed4c73c750e53353e77f7c6942803809a9d5dedc28d8b0f41ce58b8b17/hosts”, “LogPath”: “/var/lib/docker/containers/98d119ed4c73c750e53353e77f7c6942803809a9d5dedc28d8b0f41ce58b8b17/98d119ed4c73c750e53353e77f7c6942803809a9d5dedc28d8b0f41ce58b8b17-json.log”, “Name”: “/tomcat001”, “RestartCount”: 0, “Driver”: “aufs”, “MountLabel”: “”, “ProcessLabel”: “”, “AppArmorProfile”: “”, “ExecIDs”: [ “cffec99f38514024f6a6e31e0e160d37d295041e4813a2245466be2dbc9c4037” ], “HostConfig”: { “Binds”: null, “ContainerIDFile”: “”, “LogConfig”: { “Type”: “json-file”, “Config”: {} }, “NetworkMode”: “default”, “PortBindings”: {}, “RestartPolicy”: { “Name”: “no”, “MaximumRetryCount”: 0 }, “AutoRemove”: false, “VolumeDriver”: “”, “VolumesFrom”: null, “CapAdd”: null, “CapDrop”: null, “Dns”: [], “DnsOptions”: [], “DnsSearch”: [], “ExtraHosts”: null, “GroupAdd”: null, “IpcMode”: “”, “Cgroup”: “”, “Links”: null, “OomScoreAdj”: 0, “PidMode”: “”, “Privileged”: false, “PublishAllPorts”: false, “ReadonlyRootfs”: false, “SecurityOpt”: null, “UTSMode”: “”, “UsernsMode”: “”, “ShmSize”: 67108864, “Runtime”: “runc”, “ConsoleSize”: [ 0, 0 ], “Isolation”: “”, “CpuShares”: 0, “Memory”: 0, “NanoCpus”: 0, “CgroupParent”: “”, “BlkioWeight”: 0, “BlkioWeightDevice”: null, “BlkioDeviceReadBps”: null, “BlkioDeviceWriteBps”: null, “BlkioDeviceReadIOps”: null, “BlkioDeviceWriteIOps”: null, “CpuPeriod”: 0, “CpuQuota”: 0, “CpuRealtimePeriod”: 0, “CpuRealtimeRuntime”: 0, “CpusetCpus”: “”, “CpusetMems”: “”, “Devices”: [], “DiskQuota”: 0, “KernelMemory”: 0, “MemoryReservation”: 0, “MemorySwap”: 0, “MemorySwappiness”: -1, “OomKillDisable”: false, “PidsLimit”: 0, “Ulimits”: null, “CpuCount”: 0, “CpuPercent”: 0, “IOMaximumIOps”: 0, “IOMaximumBandwidth”: 0 }, “GraphDriver”: { “Name”: “aufs”, “Data”: null }, “Mounts”: [], “Config”: { “Hostname”: “98d119ed4c73”, “Domainname”: “”, “User”: “”, “AttachStdin”: false, “AttachStdout”: false, “AttachStderr”: false, “ExposedPorts”: { “8080/tcp”: {} }, “Tty”: true, “OpenStdin”: true, “StdinOnce”: false, “Env”: [ “PATH=/usr/local/tomcat/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin”, “LANG=C.UTF-8”, “JAVA_HOME=/docker-java-home/jre”, “JAVA_VERSION=8u151”, “JAVA_DEBIAN_VERSION=8u151-b12-1~deb9u1”, “CA_CERTIFICATES_JAVA_VERSION=20170531+nmu1”, “CATALINA_HOME=/usr/local/tomcat”, “TOMCAT_NATIVE_LIBDIR=/usr/local/tomcat/native-jni-lib”, “LD_LIBRARY_PATH=/usr/local/tomcat/native-jni-lib”, “OPENSSL_VERSION=1.1.0f-3+deb9u1”, “GPG_KEYS=05AB33110949707C93A279E3D3EFE6B686867BA6 07E48665A34DCAFAE522E5E6266191C37C037D42 47309207D818FFD8DCD3F83F1931D684307A10A5 541FBE7D8F78B25E055DDEE13C370389288584E7 61B832AC2F1C5A90F0F9B00A1C506407564C17A3 713DA88BE50911535FE716F5208B0AB1D63011C7 79F7026C690BAA50B92CD8B66A3AD3F4F22C4FED 9BA44C2621385CB966EBA586F72C284D731FABEE A27677289986DB50844682F8ACB77FC2E86E29AC A9C5DF4D22E99998D9875A5110C01C5A2F6059E7 DCFD35E0BF8CA7344752DE8B6FB21E8933C60243 F3A04C595DB5B6A5F1ECA43E3B7BBB100D811BBE F7DA48BB64BCB84ECBA7EE6935CD23C10D498E23”, “TOMCAT_MAJOR=8”, “TOMCAT_VERSION=8.5.24”, “TOMCAT_SHA1=9e26ba61c5665aafc849073edeb769be555283cd”, “TOMCAT_TGZ_URLS=https://www.apache.org/dyn/closer.cgi?action=download&filename=tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz thttps://www-us.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz thttps://www.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz thttps://archive.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz”, “TOMCAT_ASC_URLS=https://www.apache.org/dyn/closer.cgi?action=download&filename=tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc thttps://www-us.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc thttps://www.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc thttps://archive.apache.org/dist/tomcat/tomcat-8/v8.5.24/bin/apache-tomcat-8.5.24.tar.gz.asc” ], “Cmd”: [ “catalina.sh”, “run” ], “ArgsEscaped”: true, “Image”: “tomcat”, “Volumes”: null, “WorkingDir”: “/usr/local/tomcat”, “Entrypoint”: null, “OnBuild”: null, “Labels”: {} }, “NetworkSettings”: { “Bridge”: “”, “SandboxID”: “50244517221e6faff4217ff5453919f0c297b10434812ecfbf3decb3ce9860f6”, “HairpinMode”: false, “LinkLocalIPv6Address”: “”, “LinkLocalIPv6PrefixLen”: 0, “Ports”: { “8080/tcp”: null }, “SandboxKey”: “/var/run/docker/netns/50244517221e”, “SecondaryIPAddresses”: null, “SecondaryIPv6Addresses”: null, “EndpointID”: “e9336feece03b1c87e6724253575ee50963e9bdc1f9618609fe641a8a939b87a”, “Gateway”: “172.17.0.1”, “GlobalIPv6Address”: “”, “GlobalIPv6PrefixLen”: 0, “IPAddress”: “172.17.0.5”, “IPPrefixLen”: 16, “IPv6Gateway”: “”, “MacAddress”: “02:42:ac:11:00:05”, “Networks”: { “bridge”: { “IPAMConfig”: null, “Links”: null, “Aliases”: null, “NetworkID”: “87eb4d08d408c08489db4460915aabed59210d04f8193364420d3719cd308d83”, “EndpointID”: “e9336feece03b1c87e6724253575ee50963e9bdc1f9618609fe641a8a939b87a”, “Gateway”: “172.17.0.1”, “IPAddress”: “172.17.0.5”, “IPPrefixLen”: 16, “IPv6Gateway”: “”, “GlobalIPv6Address”: “”, “GlobalIPv6PrefixLen”: 0, “MacAddress”: “02:42:ac:11:00:05” } } } } ]

可见内容十分丰富；

如果我们只对其中的一些感兴趣，例如hostname、ip地址、环境变量，该如何查看呢？

hostname：在返回值中，hostname的位置如下图红框所示，

由上图可见，hostname位于Config.Hostname这个节点位置，所以执行命令docker inspect -f {{.Config.Hostname}} tomcat001即可获取到hostname，如下所示：

root@maven:~# docker inspect -f {{.Config.Hostname}} tomcat001 98d119ed4c73

ip地址：执行命令docker inspect -f {{.NetworkSettings.IPAddress}} tomcat001即可获取到ip地址：

root@maven:~# docker inspect -f {{.NetworkSettings.IPAddress}} tomcat001 172.17.0.5

环境变量：从完整的inspect信息中可以看到环境变量Config.Env的内容是个json数组，所以除了用docker inspect -f {{.Config.Env}} tomcat001获取所有环境变量信息，还可以用docker inspect -f ‘{{index .Config.Env 1}}’ tomcat001命令获取数组中的某一条记录，如下：

root@maven:~# docker inspect -f {{index .Config.Env 1}} tomcat001 LANG=C.UTF-8 root@maven:~# docker inspect -f {{index .Config.Env 2}} tomcat001 JAVA_HOME=/docker-java-home/jre

至此，三种获取容器信息的方式已经全部列出，之所以在本文中推荐第三种，是因为有时我们会在shell脚本中获取容器信息，这时候用这种方式最为简单；