Some linux commands that I use often
Abstract
When you deploy your service on the cloud you frequently need to ssh
in the instance and check something on the server. Most likely you will have to check some logs, monitor cpu and memory usages.
Thing I do often
$ free -m
Check the available memory on your machine
$ ps aux --sort -rss | head
Display processes with top 10 memory usage (not working on a Mac)
$ df -h
check the avilable disk space
$ last
check last ssh-in user
$ tail xxx.txt -n 20
read the last 20 lines of xxx.txt, you can also ignore the -n part
$ whoami
this tell you who you are.
$ ll
check file permissions. detailed explaination can check this link http://mason.gmu.edu/~montecin/UNIXpermiss.htm
$ sudo -u username xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
you can run processes using different username
$ lsof -t -i :8000 | xargs ps -fp
checking what program is listening port 8000
tail -f /proc/1234/fd/1
Check the outputs of a running process with pid 1234
(not working on a mac)
⌘ + D
Split the window
Shift + ⌘ + D
Undo split the window
ls -l
Check file and folder owners.
ll
Check file and folder owners, even the hidden files.
utilities that I use
- ncdu (use this to check disk space and usage)
- screen (use this to open multiple screens and run processes in them)
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references:
16 Nov 2015