This morning I noticed someone had stuck a USB Drive in the back of the server. (I'll have to end that practice later). For some reason CentOS 7 mounted that disk /dev/sdc1 under /run/media//. I also noticed when I ran
df that my /dev/mapper/centos-root was full. Ok, ran through / with
du and noticed that the flash drive had mounted itself here and took up the remaining space somehow.
So I ran
umount /run/media/<user>/<uuid> and it went away. Great. Except
df still states that I'm full and the server is experiencing issues common with low disk space. Worse now, a reboot of the server left me only able to get into maintenance mode. How do I free up this space or even know what is bound to the fs?
EDIT: This is essentially another
df -H doesn't agree with
du problem. According to df I have only 800MB/54GB free on root and I can't boot because of it. But by using
du -h --max-depth 1 /mnt/sysimage/ (where /mnt/sysimage/ is just / because I'm in recovery mode right now). It outputs something like this (can't directly copy):
264M /mnt/sysimage/boot 0 /mnt/sysimage/dev 26G /mnt/sysimage/home 0 /mnt/sysimage/proc ... small stuff - MB scale 1.7G /mnt/sysimage/var
So how do those add up to fill a 54GB disk? As stated above before it crashed, this mystery USB drive had been mounted in
/run/media/<user>/<uuid> and was thus under / Could this still be bound to the file system?