disk space

this command will find the largest files on the system and list them in order

find / -mount -type f -ls | sort -rnk7 | head -30 | awk '{printf "%d MB\t%s\n",($7/1024)/1024,$NF}'

useful sometimes

du -hcx --max-depth=5 / | grep [0-9]G

*** free up some space ***

logrotate --force /etc/logrotate.d/*
yum --enablerepo=’*’ clean all
rm -rf /var/cache/yum

*** command that will report the size of deleted files that are open ***

lsof | head -n 1; lsof | grep deleted | sort -u -k8 | sort -nr -k7 | head -n 5

*** reducing the reserved block size ***

tune2fs -l 
... Reserved block count:  ...
Adjust Accordingly:
tune2fs -m  
make sure to revert reserved blocks back to original setting