I have a server which has a handful of services (Apache, MySQL, DNS, Nagios), and have been having issues with the harddrive filling up. Upon further review, I noticed that the percentage used according to df doesn't make any sense. Used space plus available space does not equal total space. At the time I first became aware of this (thanks to a Nagios notification), the available space was less than 1 GB out of our 40 GB harddrive. According to du and df Used column, the actual used was 11GB. That's a difference of 28GB. At the moment it's fluctuating only a little, but sometimes it fluctuates at over 1000 bytes per second. See here:$ df / && sleep 5 && df /Filesystem           1K-blocks      Used Available Use% Mounted on/dev/vzfs             41943040  11398324  29195724  29% /Filesystem           1K-blocks      Used Available Use% Mounted on/dev/vzfs             41943040  11398324  29173016  29% /This is a VPS that I don't have physical access to. It's running XFS, so a normal reboot fsck isn't an option either. It doesn't do it constantly, and log files don't seem to indicate anything going on. iotop doesn't even show any activity at all. Twist, we have people actively using this machine so we can't just format.Output of df -a:$ sudo df -aFilesystem           1K-blocks      Used Available Use% Mounted on/dev/vzfs             41943040  11398740  29064180  29% /proc                         0         0         0   -  /procsysfs                        0         0         0   -  /sysnone                    524288         4    524284   1% /devnone                         0         0         0   -  /dev/ptsnone                   5242880        12   5242868   1% /var/tmpfsnone                         0         0         0   -  /proc/sys/fs/binfmt_misc/etc/named            41943040  11398740  29064180  29% /var/named/chroot/etc/named/var/named            41943040  11398740  29064180  29% /var/named/chroot/var/named/etc/named.rfc1912.zones                      41943040  11398748  29064172  29% /var/named/chroot/etc/named.rfc1912.zones/etc/rndc.key         41943040  11398748  29064172  29% /var/named/chroot/etc/rndc.key/usr/lib64/bind       41943040  11398756  29064164  29% /var/named/chroot/usr/lib64/bind/etc/named.iscdlv.key                      41943040  11398764  29064156  29% /var/named/chroot/etc/named.iscdlv.key/etc/named.root.key   41943040  11398772  29064148  29% /var/named/chroot/etc/named.root.key
Harddrive remaining space does not compute
linux;df