Quick Docker Exec

10 February, 2022

I use Docker a lot, and have always found it annoying that in order to run exec commands, I first need to use docker ps to look up the ID for the contrainer I’m trying to interact with.

I decided to write a small bash script to make this process less annoying. You can check it out here.

Features

List all running containers
Pass optional script argument(s) as an exec command
Attempt to acquire /bin/bash and /bin/sh shells as the default argument

Script parses all of the arguments given to it into a single exec command - no quotes necessary!

quickdocker.sh /bin/bash -c 'ps aux' 
# will turn into --> 
docker exec -it <POD ID> /bin/bash -c 'ps aux'

Example output

# no arguments provided, tries acquiring shells in order
$ bash quickdocker.sh

   CONTAINER ID   IMAGE           COMMAND                  STATUS              PORTS
1) dab88fc067db   ubuntu:latest   "bash"                   Up 32 minutes   
2) 61be819285e7   beanmaster      "/entrypoint.sh"         Up 16 minutes      
3) e408febcc43d   835490db8cd7    "/docker-entrypoint.…"   Up 54 minutes   0.0.0.0:80->80/tcp, :::80->80/tcp
Container to exec: 2
Running /bin/bash

OCI runtime exec failed: exec failed: container_linux.go:380: starting container process caused: exec: "/bin/bash": stat /bin/bash: no such file or directory: unknown
/bin/bash not available in container
Running /bin/sh
~ # 

# arguments provided, attempts running them as exec command
$ bash quickdocker.sh /bin/bash -c "hostname -I"

   CONTAINER ID   IMAGE           COMMAND                  STATUS             PORTS
1) dab88fc067db   ubuntu:latest   "bash"                   Up 35 minutes      
2) 61be819285e7   beanmaster      "/entrypoint.sh"         Up 19 minutes      
3) e408febcc43d   835490db8cd7    "/docker-entrypoint.…"   Up 54 minutes   0.0.0.0:80->80/tcp, :::80->80/tcp
Container to exec: 1
Running '/bin/bash -c hostname -I'

172.17.0.5