Docker Debug چیست و چه مشکلی را حل می کند؟

docker debug --help


Usage:  docker debug [OPTIONS] {CONTAINER|IMAGE}

Get an enhanced shell with additional tools into any container or image

Options:
  -c, --command string   Evaluate the specified commands instead, passing additional positional arguments through
                         $argv.
      --host string      Daemon docker socket to connect to. E.g.: 'ssh://root@example.org',
                         'unix:///some/path/docker.sock'
      --shell shell      Select a shell. Supported: "bash", "fish", "zsh", "auto". (default auto)
      --version          Display version of the docker-debug plugin

docker debug nginx
Pulling image, this might take a moment...
0.0.22: Pulling from docker/desktop-docker-debug-service
10c7e62bcff5: Pull complete
Digest: sha256:60b0227c4304f2d703255448aba2863c9a97e21ad0233514de3c7f200904869f
Status: Downloaded newer image for docker/desktop-docker-debug-service:0.0.22
latest: Pulling from library/nginx
a5573528b1f0: Pull complete
8897d65c8417: Pull complete
fbc138d1d206: Pull complete
06f386eb9182: Pull complete
aeb2f3db77c3: Pull complete
64fb762834ec: Pull complete
e5a7e61f6ff4: Pull complete
Digest: sha256:4c0fdaa8b6341bfdeca5f18f7837462c80cff90527ee35ef185571e1c327beac
Status: Downloaded newer image for nginx:latest
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  ▀████████▀    █▄▀ █▄█ █▄▄ █ █ ██▄ █▀▄
   ▀█████▀                        DEBUG

Builtin commands:
- install [tool1] [tool2] ...    Add Nix packages from: https://search.nixos.org/packages
- uninstall [tool1] [tool2] ...  Uninstall NixOS package(s).
- entrypoint                     Print/lint/run the entrypoint.
- builtins                       Show builtin commands.

Checks:
✓ distro:            Debian GNU/Linux 12 (bookworm)
✓ entrypoint linter: no errors (run 'entrypoint' for details)

Note: This is a sandbox shell. All changes will not affect the actual image.
                                                                                                   Version: 0.0.22 (BETA)
root@6c7be49d2a11 / [nginx:latest]
docker >

docker > entrypoint
Understand how ENTRYPOINT/CMD work and if they are set correctly.
From CMD in Dockerfile:
 ['nginx', '-g', 'daemon off;']

From ENTRYPOINT in Dockerfile:
 ['/docker-entrypoint.sh']

/docker-entrypoint.sh nginx -g daemon off;

path: /docker-entrypoint.sh
args: nginx -g daemon off;
cwd:
PATH: /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

Lint results:
 PASS: '/docker-entrypoint.sh' found
 PASS: no mixing of shell and exec form
 PASS: no double use of shell form

Docs:
- https://docs.docker.com/engine/reference/builder/#cmd
- https://docs.docker.com/engine/reference/builder/#entrypoint
- https://docs.docker.com/engine/reference/builder/#understand-how-cmd-and-entrypoint-interact
root@6c7be49d2a11 / [nginx:latest]

builtins
A docker debugging toolbox.                                                                                        0.0.22

Builtin commands:
- install [tool1] [tool2] ...    Add Nix packages from: https://search.nixos.org/packages
- uninstall [tool1] [tool2] ...  Uninstall NixOS package(s).
- entrypoint                     Print/lint/run the entrypoint.
- builtins                       Show builtin commands.

Note: This is a sandbox shell. All changes will not affect the actual image.
                                                                                                   Version: 0.0.22 (BETA)
root@6c7be49d2a11 / [nginx:latest]

install crossplane
Tip: You can install any package available at: https://search.nixos.org/packages.
[2024-01-22T07:13:47.863328585Z][W] tcp keep alive: request failed (Not Found): 404
[2024-01-22T07:13:52.866284045Z][W] tcp keep alive: request failed (Not Found): 404
installing 'crossplane-0.5.8'
these 2 paths will be fetched (0.07 MiB download, 0.26 MiB unpacked):
  /nix/store/dnyyy0nbr9ybyh6b49b450arp3d4zgnq-python3.10-crossplane-0.5.8
  /nix/store/ah81s4zhrdiz24avnfj92jw440kxy7f0-python3.10-crossplane-0.5.8-dist
copying path '/nix/store/dnyyy0nbr9ybyh6b49b450arp3d4zgnq-python3.10-crossplane-0.5.8' from 'https://cache.nixos.org'...
copying path '/nix/store/ah81s4zhrdiz24avnfj92jw440kxy7f0-python3.10-crossplane-0.5.8-dist' from 'https://cache.nixos.org'...
building '/nix/store/ryyfmaqkmy80333cprzipb8v82ghl5nf-user-environment.drv'...
root@6c7be49d2a11 / [nginx:latest]

docker > bash -c "cat /usr/share/nginx/html/index.html"








If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.

For online documentation and support please refer to
nginx.org.
Commercial support is available at
nginx.com.

Thank you for using nginx.


root@6c7be49d2a11 / [nginx:latest]
docker >

docker > vim
root@6c7be49d2a11 / [nginx:latest]
docker > vi hello
root@6c7be49d2a11 / [nginx:latest]
docker > ls
bin   dev                  docker-entrypoint.sh  hello  lib    mnt  opt   root  sbin  sys  usr
boot  docker-entrypoint.d  etc                   home   media  nix  proc  run   srv   tmp  var
root@6c7be49d2a11 / [nginx:latest]
docker >

which vim
/nix/var/nix/profiles/default/bin/vim
root@6c7be49d2a11 / [nginx:latest]

root@6c7be49d2a11 / [nginx:latest]
docker > forward --port 81:80 nginx
2024/01/22 09:54:02 [notice] 59#59: using the "epoll" event method
2024/01/22 09:54:02 [notice] 59#59: nginx/1.25.3
2024/01/22 09:54:02 [notice] 59#59: built by gcc 12.2.0 (Debian 12.2.0-14)
2024/01/22 09:54:02 [notice] 59#59: OS: Linux 6.6.12-linuxkit
2024/01/22 09:54:02 [notice] 59#59: getrlimit(RLIMIT_NOFILE): 1048576:1048576
2024/01/22 09:54:02 [notice] 64#64: start worker processes
2024/01/22 09:54:02 [notice] 64#64: start worker process 65
2024/01/22 09:54:02 [notice] 64#64: start worker process 66
2024/01/22 09:54:02 [notice] 64#64: start worker process 67
2024/01/22 09:54:02 [notice] 64#64: start worker process 68
2024/01/22 09:54:02 [notice] 64#64: start worker process 69
2024/01/22 09:54:02 [notice] 64#64: start worker process 70
2024/01/22 09:54:02 [notice] 64#64: start worker process 71
2024/01/22 09:54:02 [notice] 64#64: start worker process 72

docker run -d -p 6379:6379 redis

docker ps
CONTAINER ID   IMAGE     COMMAND                  CREATED          STATUS          PORTS                    NAMES
a1ce95fc8430   redis     "docker-entrypoint.s…"   26 seconds ago   Up 26 seconds   0.0.0.0:6379->6379/tcp   eloquent_hamilton

docker debug eloquent_hamilton
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  ▀████████▀    █▄▀ █▄█ █▄▄ █ █ ██▄ █▀▄
   ▀█████▀                        DEBUG

Builtin commands:
- install [tool1] [tool2] ...    Add Nix packages from: https://search.nixos.org/packages
- uninstall [tool1] [tool2] ...  Uninstall NixOS package(s).
- entrypoint                     Print/lint/run the entrypoint.
- builtins                       Show builtin commands.

Checks:
✓ distro:            Debian GNU/Linux 12 (bookworm)
✓ entrypoint linter: no errors (run 'entrypoint' for details)

This is an attach shell, i.e.:
- Any changes to the container filesystem are visible to the container directly.
- The /nix directory is invisible to the actual container.
                                                                                                                           Version: 0.0.22 (BETA)
redis@a1ce95fc8430 /data [eloquent_hamilton]
docker > ps -aef
UID        PID  PPID  C STIME TTY          TIME CMD
redis        1     0  0 10:08 ?        00:00:04 redis-server *:6379
root        47     0  0 10:24 pts/0    00:00:00 /bin/sh
root        54    47  0 10:24 pts/0    00:00:00 bash
redis       57     0  0 10:29 pts/0    00:00:00 /nix/var/nix/profiles/default/bin/zsh -i
redis       69    57  0 10:29 pts/0    00:00:00 ps -aef
redis@a1ce95fc8430 /data [eloquent_hamilton]
docker >

docker > install nmap
Tip: You can install any package available at: https://search.nixos.org/packages.
[2024-01-22T10:36:46.561468511Z][W] tcp keep alive: request failed (Not Found): 404
[2024-01-22T10:36:51.567299097Z][W] tcp keep alive: request failed (Not Found): 404
replacing old 'nmap-7.93'
installing 'nmap-7.93'
redis@a1ce95fc8430 /data [eloquent_hamilton]

docker > nmap -v -A scanme.nmap.org
Starting Nmap 7.93 ( https://nmap.org ) at 2024-01-22 10:38 UTC
NSE: Loaded 155 scripts for scanning.
NSE: Script Pre-scanning.
Initiating NSE at 10:38
Completed NSE at 10:38, 0.00s elapsed
Initiating NSE at 10:38
Completed NSE at 10:38, 0.00s elapsed
Initiating NSE at 10:38
Completed NSE at 10:38, 0.00s elapsed
Initiating Ping Scan at 10:38
Scanning scanme.nmap.org (45.33.32.156) [2 ports]
Completed Ping Scan at 10:38, 0.22s elapsed (1 total hosts)
Initiating Parallel DNS resolution of 1 host. at 10:38
Completed Parallel DNS resolution of 1 host. at 10:38, 0.84s elapsed
Initiating Connect Scan at 10:38
Scanning scanme.nmap.org (45.33.32.156) [1000 ports]
Discovered open port 80/tcp on 45.33.32.156
Discovered open port 22/tcp on 45.33.32.156