Df not updating --filesystem says its full

Question

Hi everyone. I have the strangest problem. du says my home directory contains less than 100M. df says its full (1GB). Even though df says its full, i can still create about 50M worth of files there. Then when i delete the files, df still says the filesystem is full. Any help would be very much appreciated. This is OEL5 and the last thing i did was install sqldeveloper.
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[root@ajax home]# cd /home
[root@ajax home]# du -h --max-depth=1
32K ./private
748K ./private
16K ./lost+found
36K ./private
13M ./oracle
32K ./private
14M .
[root@ajax home]# df -h |grep home
/dev/mapper/vg00-lvhome 992M 946M 0 100% /home
[root@ajax oracle]# cat TEST>>TEST2
[root@ajax oracle]# cat TEST2>>TEST
[root@ajax oracle]# cat TEST>>TEST2
[root@ajax oracle]# cat TEST2>>TEST
[root@ajax oracle]# cat TEST>>TEST2
cat: write error: No space left on device
[root@ajax home]# ls -lh TEST*
-rw-r--r-- 1 root dba 21M Aug 19 08:06 TEST
-rw-r--r-- 1 root dba 26M Aug 19 08:06 TEST2
[root@ajax oracle]# rm TEST*
rm: remove regular file `TEST'? y
rm: remove regular file `TEST2'? y
[root@ajax home]# df -h |grep home
/dev/mapper/vg00-lvhome 992M 946M 0 100% /home
So neither du nor df seems correct. Df clearly isn’t correct because I can create files and then after I delete them it still reports the same thing. Du doesn’t seem correct or I should be able to create about another 900M of files on /home

Answer 1

Hi DaveLehr,
One of the possibility is the file you removed for space was being used by some process/application.
Linux will allow you remove that without any warning.
After that, the file is invisible by "ls -l", or "du -h --max-depth=1"
but the space of that file won't be released until the last process who is using that file close it.
After that, you can see as you expect from "df -h"
since you've already rebooted ur machine, This is only one of the possibility. :)
see as below:
# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
9.5G 8.6G 377M 96% /
# dd if=/dev/zero of=zero bs=1M count=300
# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
9.5G 8.9G 77M 100% /
# du -h --max-depth=1
301M .
# open another console and edit the file, don't close it
# vi zero
# lsof | grep "tftpboot/zero"
vi 15534 root 3r REG 253,0 314572800 196618 /tftpboot/zero
# rm -f zero
# lsof | grep "tftpboot/zero"
vi 15076 root 3r REG 253,0 314572800 196618 /tftpboot/zero (deleted)
# du -h --max-depth=1
76K .
# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
9.5G 8.9G 77M 100% /
# switch to the other console and close it
# exit vi
# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
9.5G 8.6G 377M 96% /
Message was edited by:
rwen