# kubectl debug

kubectl debug -it ephemeral-demo --image=busybox:1.28 --target=ephemeral-demo
kubect debug -it <pod_name> --image=<image_as_debug_tool> --target=<target_container_name>

## 原本Pod無 top / ps指令
❯ oc exec -it caturday-6c5f74f5d6-72zs4 top
kubectl exec [POD] [COMMAND] is DEPRECATED and will be removed in a future version. Use kubectl exec [POD] -- [COMMAND] instead.
Defaulted container "caturday" out of: caturday, debugger-lnwnh (ephem)
ERRO[0000] exec failed: unable to start container process: exec: "top": executable file not found in $PATH
command terminated with exit code 255
❯ oc exec -it caturday-6c5f74f5d6-72zs4 ps
kubectl exec [POD] [COMMAND] is DEPRECATED and will be removed in a future version. Use kubectl exec [POD] -- [COMMAND] instead.
Defaulted container "caturday" out of: caturday, debugger-lnwnh (ephem)
ERRO[0000] exec failed: unable to start container process: exec: "ps": executable file not found in $PATH
command terminated with exit code 255

## 利用kubectl debug attach一個具備指令的container


❯ kubectl debug -n jace -it caturday-6c5f74f5d6-72zs4 --image=quay.io/bedrock/ubuntu:xenial-20210804 --target=caturday
Targeting container "caturday". If you don't see processes from this container it may be because the container runtime doesn't support this feature.
Defaulting debug container name to debugger-lnwnh.
If you don't see a command prompt, try pressing enter.
1000700000@caturday-6c5f74f5d6-72zs4:/$
1000700000@caturday-6c5f74f5d6-72zs4:/$
1000700000@caturday-6c5f74f5d6-72zs4:/$ ps
    PID TTY          TIME CMD
     36 pts/0    00:00:00 bash
     44 pts/0    00:00:00 ps
1000700000@caturday-6c5f74f5d6-72zs4:/$ ps aux
USER         PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
1000700+       1  0.0  0.0 109992  1928 ?        Ssl  01:46   0:00 /caturday
1000700+      36  0.2  0.0  18236  3268 pts/0    Ss   02:44   0:00 /bin/bash
1000700+      45  0.0  0.0  34428  2848 pts/0    R+   02:45   0:00 ps aux
1000700000@caturday-6c5f74f5d6-72zs4:/$ top
top - 02:45:18 up  1:00,  0 users,  load average: 4.18, 3.42, 4.23
Tasks:   3 total,   1 running,   2 sleeping,   0 stopped,   0 zombie
%Cpu(s): 14.7 us,  7.6 sy,  0.0 ni, 75.0 id,  0.2 wa,  1.6 hi,  1.0 si,  0.0 st
KiB Mem : 16352232 total,   295352 free, 11517608 used,  4539272 buff/cache
KiB Swap:        0 total,        0 free,        0 used.  3786044 avail Mem

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND
      1 1000700+  20   0  109992   1928      0 S   0.0  0.0   0:00.10 caturday