Favorite sysadmin commands

sysadmin_commands.sh

# List all crontabs on a box (from http://stackoverflow.com/questions/134906/how-do-i-list-all-cron-jobs-for-all-users)
for user in $(cut -f1 -d: /etc/passwd); do sudo crontab -u $user -l; done

# See what's eating up disk space
sudo du -h / | grep '[0-9]G'

# Multiple ssh, install i2cssh
# cmd+shift+i to broadcast'
# Terminal.app alternative is csshx
i2cssh -mdj1,dj2,dj3,dj4,dj5

# List dirs in current dir with their total size, date and name, ordered by date
ls -lt | tail -n +2 | awk '{ name = $9; ("du -hs " name " | cut -f1") | getline size; date = $7 "-" $6 ":" $8; print size "\t" date "\t" name }'

# Su as another user (here deploy) sharing SSH key when sshed
chgrp -R deploy $(dirname $SSH_AUTH_SOCK) && chmod -R g+wx $(dirname $SSH_AUTH_SOCK) && sudo -u deploy /bin/bash