根工作区的含义 - 执行 docker 运行命令

Question

我执行了一个docker 运行命令，如下所示

docker run -it --rm --net=host tensorrtserver_client

当我执行这个命令时，我看到命令提示符改变了

来自

Rajini@server_name

到

root@server_name :/#

上面命令中的'it'不是interactive吗？

你能告诉我这里发生了什么吗？

如果它是用图像启动容器 'tensorrtserver_client'，那么它不应该进入容器提示符吗？并显示类似 container_id :#?

请找到我遵循的 link 到 docker 文件和过程

https://github.com/NVIDIA/tensorrt-inference-server/blob/master/Dockerfile.client

https://docs.nvidia.com/deeplearning/sdk/tensorrt-inference-server-guide/docs/quickstart.html

Answer 1

a) 如果您使用默认 docker0 网络并且没有指定 --hostname 容器，那么它的行为如下：

shubuntu1@shubuntu1:~$ docker run -it ubuntu /bin/bash
root@0ad9bd6bfc90:/#

b) 如果您使用默认 docker0 并指定 --hostname 容器，它将像：

shubuntu1@shubuntu1:~$ docker run -it --hostname=abc ubuntu /bin/bash
root@abc:/#

c) 如果你不使用docker0，根据你的情况使用--net=host，那么它会共享主机的网络。然后，如果您没有指定 --hostname，它将为您的容器提供一个隐式主机名，与您的 docker 主机名相同：

shubuntu1@shubuntu1:~$ docker run -it --net=host ubuntu /bin/bash
root@shubuntu1:/#

所以上面 c) 意味着你已经在容器提示中。

Answer 2

来自文档 (docker run --help)：

-i, --interactive                    Keep STDIN open even if not attached
-t, --tty                            Allocate a pseudo-TTY

所以“-it”本身并不存在，而是“-i -t”的缩写。

docker run 启动一个容器并在该容器内执行给定的命令。如果提供的命令实际打开它，“-it”选项仅指示 docker 保持标准打开（显示提示）。

运行 docker run 就像用 ssh 连接到远程主机。进行身份验证后，您会看到在远程主机上定义的提示。在 docker run 之后，您会看到提示，因为它是由容器内的操作系统定义的，或者是在镜像构建期间如何配置的（在 Dockerfile 中定义）。

简而言之，如果提示发生变化，那么您的命令就成功了。如果没有，则说明您不在容器内。

希望对您有所帮助

Answer 3

你有 root@server_name :/# 因为 /bin/bash 是 tensorrtserver_client 图像的默认入口点。

我尝试了这些步骤：

运行 tensorrtserver_client 容器

[node1] (local) root@192.168.0.38 ~/tensorrt-inference-server
$ docker run -it --rm --net=host tensorrtserver_client
root@node1:/workspace#
root@node1:/workspace# ps -ef
UID         PID   PPID  C STIME TTY          TIME CMD
root          1      0  0 05:55 pts/0    00:00:00 /bin/bash
root         12      1  0 05:55 pts/0    00:00:00 ps -ef
root@node1:/workspace# exit
[node1] (local) root@192.168.0.38 ~/tensorrt-inference-server
$

得到 root@node1:/workspace# 因为 /workspace 是在 dockerfile 中设置的默认工作目录，而 root 是该图像的默认用户。
在运行执行 docker run 命令后，您还进入了 /bin/bash shell，因为 /bin/bash 是该图像的默认入口点。您可以通过运行执行以下命令来验证这一点：

$ docker inspect tensorrtserver_client
[
    {
        "Id": "sha256:90fd86dbcced04a0c585f96debc5a43b5e96bf5adfde5c7f71469d50e51ee3cd",
        "RepoTags": [
            "client:latest"
        ],
        "RepoDigests": [],
        "Parent": "sha256:8594a21faf37dbad5a9a8a2bd0129b26ebb68a6ba07a145824b29a6df90d108b",
        "Comment": "",
        "Created": "2019-06-20T05:06:55.754977279Z",
        "Container": "5b6ba9901c854df63128ead1ec7d33ceab5de0d94713a59d18eda726b03b8c76",
        "ContainerConfig": {
            "Hostname": "5b6ba9901c85",
            "Domainname": "",
            "User": "",
            "AttachStdin": false,
            "AttachStdout": false,
            "AttachStderr": false,
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=//workspace/install/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                "DEBIAN_FRONTEND=noninteractive",
                "LD_LIBRARY_PATH=/workspace/install/lib:"
            ],
            "Cmd": [
                "/bin/sh",
                "-c",
                "#(nop) ",
                "ENV LD_LIBRARY_PATH=/workspace/install/lib:"
            ],
            "ArgsEscaped": true,
            "Image": "sha256:8594a21faf37dbad5a9a8a2bd0129b26ebb68a6ba07a145824b29a6df90d108b",
            "Volumes": null,
            "WorkingDir": "/workspace",
            "Entrypoint": null,
            "OnBuild": null,
            "Labels": {}
        },
        "DockerVersion": "19.03.0-beta2",
        "Author": "",
        "Config": {
            "Hostname": "",
            "Domainname": "",
            "User": "",
            "AttachStdin": false,
            "AttachStdout": false,
            "AttachStderr": false,
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=//workspace/install/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                "DEBIAN_FRONTEND=noninteractive",
                "LD_LIBRARY_PATH=/workspace/install/lib:"
            ],
            "Cmd": [
                "/bin/bash"
            ],
            "ArgsEscaped": true,
            "Image": "sha256:8594a21faf37dbad5a9a8a2bd0129b26ebb68a6ba07a145824b29a6df90d108b",
            "Volumes": null,
            "WorkingDir": "/workspace",
            "Entrypoint": null,
            "OnBuild": null,
            "Labels": null
        },
        "Architecture": "amd64",
        "Os": "linux",
        "Size": 2315059023,
        "VirtualSize": 2315059023,
        "GraphDriver": {
            "Data": {
                "LowerDir": "/var/lib/docker/overlay2/403233de5c00747b4a081a690b387da1738e7a00254fc1df54dbd36709971637/diff:/var/lib/docker/overlay2/88e55cce134753ec862d10327241d8b3fcf17c37b367eb6c0cc4a174ad680dff/diff:/var/lib/docker/overlay2/cc4b321d2464be848bf8c2eb641761fecaf0f018b425c4bac56f83b102b4284d/diff:/var/lib/docker/overlay2/6b6a22a0a32f538f30fc10f9aa7ef7ee7473bb60866d8a68e09bce8a6ac0f507/diff:/var/lib/docker/overlay2/85eda7a5ccaab757f25815af57550c0a7b2a542c50cdfa790b42441b261864fc/diff:/var/lib/docker/overlay2/ab4724f8aa278bcb3bdf94d2cfe6c4c4a4005603e46ff61ff81c17d9c92be96c/diff:/var/lib/docker/overlay2/8532010cf9fc575e15f10f62583532a39d080244014b373cee6cc7dab0106678/diff:/var/lib/docker/overlay2/bf05834ad49520b48da6087491d024d60fb4534c5570a9260ef13828c051b179/diff:/var/lib/docker/overlay2/29c653558989a2d853d501034dcf1b58e12d5bcf5b105f84271727b33e157d65/diff:/var/lib/docker/overlay2/578aa342e497269c0f025638ee66ae8a817fc33205ac2765abbc086e74fdde94/diff:/var/lib/docker/overlay2/cbe81f7aac93e8c005537aca3c5212f916717a782ff07e4987440d4733a8c4ec/diff:/var/lib/docker/overlay2/e903955578b6b93db3149c6e4c62af229689100d21f8b8726b8615cee78c214d/diff:/var/lib/docker/overlay2/46e607b2b3826f4021af2c80e41f16868d2c97ed83ea623c103af8a96302d28b/diff:/var/lib/docker/overlay2/580aa8b144b93301e2bbe0f8bb8949e77910eeaf4bb484744a073610ab398faa/diff:/var/lib/docker/overlay2/0b2c6f5f78d999e9084c91b1565e527ebb0e89e9fc80c63528332da8cbd78c83/diff:/var/lib/docker/overlay2/7f8629cdcfc2df52b06a4087c3b97530e472de12ccc01cf9d642800a85ec0253/diff",
                "MergedDir": "/var/lib/docker/overlay2/549a515d33082611583bcb0ad42b7f0d2ed9c8569ef38cecd62df2a0b12705ca/merged",
                "UpperDir": "/var/lib/docker/overlay2/549a515d33082611583bcb0ad42b7f0d2ed9c8569ef38cecd62df2a0b12705ca/diff",
                "WorkDir": "/var/lib/docker/overlay2/549a515d33082611583bcb0ad42b7f0d2ed9c8569ef38cecd62df2a0b12705ca/work"
            },
            "Name": "overlay2"
        },
        "RootFS": {
            "Type": "layers",
            "Layers": [
                "sha256:1ea5a27b0484f2a227275fbb913d281461d9f356134a56002574904c3cfdea04",
                "sha256:24ab7de5faec98f9068e68257ce51c43cb98044a108e3f7f107e60bba3ad2ef4",
                "sha256:10e46f329a252698b52d88487165156ba4a52e5b62e75e10436e4353ae6ca687",
                "sha256:92d3f22d44f3a9ffaa7bbdf9d7ba902a66d39ab8d72e791b60b63a5b813ffa31",
                "sha256:47abeda4e29f00f3889731dcda169734217a18d746c9582281e1868ac9ace405",
                "sha256:8fc379b31a250d7b871cd58226d208b6dee1e8a354087f8e7e4c1bcc96ef534e",
                "sha256:a0c43a55c96bd23d6031e0f7c47ae987253f7d4f95b78b116dd49575541a02b3",
                "sha256:aa3a23d6d3ea279a468307bcb8c0c8f14075783f0280fb4a63b9095de2400783",
                "sha256:525a96836c3ce61202e704d92f05c842a49e39f2e3c5f38f14ba53ea570e24e3",
                "sha256:7d6c0707126d5cf34fde14b7beea34ae44c535b3a3301cdf66904c4f0e03a44d",
                "sha256:d454ca1494271bc0b97298214398db2131c76489227e5aece93a7cd6ba4e5a10",
                "sha256:8d7a3022550d6afc42827dd76ae76fec2f45714244fef59625b743d06d0429e9",
                "sha256:f48bf567fc7abcb6fd201d4cc6e681810a8c2bf4ae86bc0ff05f808cd8d5ee02",
                "sha256:3e2618d9f97998a99d605e264ac282374854e1fa18dcdc92b430794de9edc782",
                "sha256:dc97ef09b5fcc5ae74457629fb8ab45dfc817c9fa9de85243045d14341d88534",
                "sha256:4aa8735a33cf1223b12dbd3e3fd4af6aa9d0f14a17f4273bc7cd04f17288b544",
                "sha256:db091c30373fbc4884cfe21a315df24643c4e8801ed2cb3d7984ecc6be4e181f"
            ]
        },
        "Metadata": {
            "LastTagTime": "2019-06-20T05:06:55.838215092Z"
        }
    }
]

在上面的输出中，您可以看到此图像的 entrypoint 设置为 null

"Entrypoint": null,

所以在这种情况下，使用默认 CMD 中提到的命令，在您的情况下是 /bin/bash。如上面提到的输出所示。

"Cmd": [

"/bin/bash"

],

如果你想覆盖默认 CMD 指定 while 运行ning docker run 命令如下：

$ docker run -it --rm --net=host client /bin/sh
# ps -ef
UID         PID   PPID  C STIME TTY          TIME CMD
root          1      0  0 05:48 pts/0    00:00:00 /bin/sh
root          7      1  0 05:49 pts/0    00:00:00 ps -ef
#

或使用 docker 运行中的 --entrypoint 选项覆盖默认 entrypoint。

$ docker run -it --rm --net=host --entrypoint /bin/sh client
# ps -ef
UID         PID   PPID  C STIME TTY          TIME CMD
root          1      0  1 05:50 pts/0    00:00:00 /bin/sh
root          6      1  0 05:50 pts/0    00:00:00 ps -ef
#

要了解更多 CMD 和 ENTRYPOINT 之间的区别，请查看 this。

希望这对您有所帮助，请告诉我。

根工作区的含义 - 执行 docker 运行命令

Meaning of root workspace - Executing docker run command

docker

dockerfile

docker-compose

docker-image

根工作区的含义 - 执行 docker 运行 命令

Meaning of root workspace - Executing docker run command

docker

dockerfile

docker-compose

docker-image

根工作区的含义 - 执行 docker 运行命令