(Docker notes): View logs, metadata, and processes

table of Contents

Commonly used other commands

Start the container in the background docker run -d

View logs docker logs

View process information in the container docker top

View the image metadata docker inspect

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Commonly used other commands

Start the container in the background docker run -d

docker run -d  centos   # 后台启动

• Description :
  • After starting docker, ps will find that centos has stopped
  • Common pit: docker container runs in the background, it must have a foreground process (that is, interactive). If docker finds that there is no application and does not provide services, it will stop immediately

View logs docker logs

docker logs --help

Usage:	docker logs [OPTIONS] CONTAINER

Fetch the logs of a container

Options:
      --details        Show extra details provided to logs
  -f, --follow         Follow log output
      --since string   Show logs since timestamp (e.g. 2013-01-02T13:23:37) or relative (e.g. 42m for 42 minutes)
      --tail string    Number of lines to show from the end of the logs (default "all")
  -t, --timestamps     Show timestamps
      --until string   Show logs before a timestamp (e.g. 2013-01-02T13:23:37) or relative (e.g. 42m for 42 minutes)

docker logs -f -t --tail 容器id  行数  # 查看容器运行日志

• Case:

#编写脚本
docker run -d centos /bin/sh -c "while true;do echo hello;sleep 1;done"

显示日志
docker logs -tf --tail 10 064deaaddcdd

View process information in the container docker top

# 查看容器内的进程信息
docker top 容器id 

View the image metadata docker inspect

# 查看容器内所有信息
docker inspect 容器id

root@:/# docker inspect 9e81a383cd92
[
    {
        # 容器id 能发现命令中的id只是这里面的一小部分
        "Id": "9e81a383cd92e049add2e7376b2591d3ebef871bf1be7ed651cfe435a0b96ad1",
        # 创建时间
        "Created": "2020-09-11T07:57:14.851996196Z",
        # 交互前台路径
        "Path": "/bin/bash",
        # 携带参数
        "Args": [],
        # 容器状态
        "State": {
            "Status": "exited",
            "Running": false,
            "Paused": false,
            "Restarting": false,
            "OOMKilled": false,
            "Dead": false,
            "Pid": 0,
            "ExitCode": 0,
            "Error": "",
            "StartedAt": "2020-09-11T08:12:17.617331424Z",
            "FinishedAt": "2020-09-11T08:13:42.863278698Z"
        },
        # 镜像来源
        "Image": "sha256:0d120b6ccaa8c5e149176798b3501d4dd1885f961922497cd0abef155c869566",
        "ResolvConfPath": "/var/lib/docker/containers/9e81a383cd92e049add2e7376b2591d3ebef871bf1be7ed651cfe435a0b96ad1/resolv.conf",
        "HostnamePath": "/var/lib/docker/containers/9e81a383cd92e049add2e7376b2591d3ebef871bf1be7ed651cfe435a0b96ad1/hostname",
        "HostsPath": "/var/lib/docker/containers/9e81a383cd92e049add2e7376b2591d3ebef871bf1be7ed651cfe435a0b96ad1/hosts",
        "LogPath": "/var/lib/docker/containers/9e81a383cd92e049add2e7376b2591d3ebef871bf1be7ed651cfe435a0b96ad1/9e81a383cd92e049add2e7376b2591d3ebef871bf1be7ed651cfe435a0b96ad1-json.log",
        "Name": "/musing_shannon",
        "RestartCount": 0,
        "Driver": "overlay2",
        "Platform": "linux",
        "MountLabel": "",
        "ProcessLabel": "",
        "AppArmorProfile": "",
        "ExecIDs": null,
        # 主机配置
        "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,
            "Capabilities": null,
            "Dns": [],
            "DnsOptions": [],
            "DnsSearch": [],
            "ExtraHosts": null,
            "GroupAdd": null,
            "IpcMode": "private",
            "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": [],
            "BlkioDeviceReadBps": null,
            "BlkioDeviceWriteBps": null,
            "BlkioDeviceReadIOps": null,
            "BlkioDeviceWriteIOps": null,
            "CpuPeriod": 0,
            "CpuQuota": 0,
            "CpuRealtimePeriod": 0,
            "CpuRealtimeRuntime": 0,
            "CpusetCpus": "",
            "CpusetMems": "",
            "Devices": [],
            "DeviceCgroupRules": null,
            "DeviceRequests": null,
            "KernelMemory": 0,
            "KernelMemoryTCP": 0,
            "MemoryReservation": 0,
            "MemorySwap": 0,
            "MemorySwappiness": null,
            "OomKillDisable": false,
            "PidsLimit": null,
            "Ulimits": null,
            "CpuCount": 0,
            "CpuPercent": 0,
            "IOMaximumIOps": 0,
            "IOMaximumBandwidth": 0,
            "MaskedPaths": [
                "/proc/asound",
                "/proc/acpi",
                "/proc/kcore",
                "/proc/keys",
                "/proc/latency_stats",
                "/proc/timer_list",
                "/proc/timer_stats",
                "/proc/sched_debug",
                "/proc/scsi",
                "/sys/firmware"
            ],
            "ReadonlyPaths": [
                "/proc/bus",
                "/proc/fs",
                "/proc/irq",
                "/proc/sys",
                "/proc/sysrq-trigger"
            ]
        },
        "GraphDriver": {
            "Data": {
                "LowerDir": "/var/lib/docker/overlay2/2787c367dc59c967fbda7ada8dfbc92e0978e0798aeb08f2c1b1b92d3310fb2a-init/diff:/var/lib/docker/overlay2/b97e21785f70e73bb18eb7664ff0525b81481b801da94cae1760bf59e59aab93/diff",
                "MergedDir": "/var/lib/docker/overlay2/2787c367dc59c967fbda7ada8dfbc92e0978e0798aeb08f2c1b1b92d3310fb2a/merged",
                "UpperDir": "/var/lib/docker/overlay2/2787c367dc59c967fbda7ada8dfbc92e0978e0798aeb08f2c1b1b92d3310fb2a/diff",
                "WorkDir": "/var/lib/docker/overlay2/2787c367dc59c967fbda7ada8dfbc92e0978e0798aeb08f2c1b1b92d3310fb2a/work"
            },
            "Name": "overlay2"
        },
        # 挂载信息
        "Mounts": [],
        # 基本配置
        "Config": {
            "Hostname": "9e81a383cd92",
            "Domainname": "",
            "User": "",
            "AttachStdin": true,
            "AttachStdout": true,
            "AttachStderr": true,
            "Tty": true,
            "OpenStdin": true,
            "StdinOnce": true,
            # 环境变量
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
            ],
            # 命令行
            "Cmd": [
                "/bin/bash"
            ],
            "Image": "centos",
            "Volumes": null,
            "WorkingDir": "",
            "Entrypoint": null,
            "OnBuild": null,
            "Labels": {
                "org.label-schema.build-date": "20200809",
                "org.label-schema.license": "GPLv2",
                "org.label-schema.name": "CentOS Base Image",
                "org.label-schema.schema-version": "1.0",
                "org.label-schema.vendor": "CentOS"
            }
        },
        # 网络设置
        "NetworkSettings": {
            "Bridge": "",
            "SandboxID": "3bfa7ee85741f9e8d1b7fe09a5fdafbf2786fad86dd9c3f1633b9ad299e05f77",
            "HairpinMode": false,
            "LinkLocalIPv6Address": "",
            "LinkLocalIPv6PrefixLen": 0,
            "Ports": {},
            "SandboxKey": "/var/run/docker/netns/3bfa7ee85741",
            "SecondaryIPAddresses": null,
            "SecondaryIPv6Addresses": null,
            "EndpointID": "",
            "Gateway": "",
            "GlobalIPv6Address": "",
            "GlobalIPv6PrefixLen": 0,
            "IPAddress": "",
            "IPPrefixLen": 0,
            "IPv6Gateway": "",
            "MacAddress": "",
            "Networks": {
            	# 当前使用的网络工作模式
                "bridge": {
                    "IPAMConfig": null,
                    "Links": null,
                    "Aliases": null,
                    "NetworkID": "0ace116fbc7bb24ece8d7e00cb9523b2d72342af0dca94b4f3ae1bd56913d98d",
                    "EndpointID": "",
                    "Gateway": "",
                    "IPAddress": "",
                    "IPPrefixLen": 0,
                    "IPv6Gateway": "",
                    "GlobalIPv6Address": "",
                    "GlobalIPv6PrefixLen": 0,
                    "MacAddress": "",
                    "DriverOpts": null
                }
            }
        }
    }
]