How to free/restore the space ?

When we tried to clean the disk space, maybe encounter this kind of issue. you rm some big files.

df -h doesn’t appear difference. but du -hs /directory seems different with df

simple answer maybe is : some process use the files. the process didn’t free it.

If you want to know details, here is the link:

http://www.cyberciti.biz/tips/freebsd-why-command-df-and-du-reports-different-output.html

sudo lsof grep ifs grep deleted

java 17059 ifs 9w REG 253,9 632315860 1212431 /apps/ifs/IFSV01/instance/IFSV01/logs/connectserver/ifsalert.0.log.1 (deleted)

ls -la /proc/17059/fd/9

l-wx—— 1 ifs ifs 64 Sep 13 02:16 /proc/17059/fd/9 -> /apps/ifs/IFSV01/instance/IFSV01/logs/connectserver/ifsalert.0.log.1 (deleted)

Now how to restore it ?

cp /proc/17059/fd/9 /apps/ifs/ifsalert.0.log.1.restored

Now how to free it ?

#> /proc/17059/fd/9

More explainations: http://www.unixwerk.eu/linux/deleted_files.html