14.04 - How to locate the directory that uses all disk space - Ask Ubuntu

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• what taking space on disk, beside filesystem? 7 answers

i have used ubuntu 14.04 server host company website , mailsystem. system online 3 weeks before not able send or receive emails. few minutes of debugging showed reason: no more disk space.

filesystem      size  used avail use% mounted on udev            3.9g     0  3.9g   0% /dev tmpfs           799m  8.7m  790m   2% /run /dev/xvda1      7.8g  7.4g     0 100% / tmpfs           3.9g     0  3.9g   0% /dev/shm tmpfs           5.0m     0  5.0m   0% /run/lock tmpfs           3.9g     0  3.9g   0% /sys/fs/cgroup tmpfs           100k     0  100k   0% /run/lxcfs/controllers tmpfs           799m     0  799m   0% /run/user/1000 

question: how can locate directory occupies disk space?

i have tried using df -hs /path/to/directory on root directories without luck. there 4gb of space not accounted for.

top 10 largest directories:

du -a / | sort -n -r | head -n 10 

in more human readable format:

du -hsx / | sort -rh | head -10 

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largest 10 files:

find / -printf '%s %p\n'| sort -nr | head -10 

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there 4gb of space not accounted for.

lots of small files add 4gb...

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i suggest @ obvious culprit:

/var/log/ 

if system has errors log them there. , errors 3 weeks can add 4gb. besides that: using databases on system? if so... check directory database stores files;/var/lib/mysql instance.