'/dev/vda1 is full but cannot find why

I have a server running Centos 7. This is the result of df -h

Filesystem                           Size  Used Avail Use% Mounted on
    udev                                 7.4G     0  7.4G   0% /dev
    tmpfs                                1.5G  139M  1.4G  10% /run
    /dev/vda1                             46G   44G     0 100% /
    tmpfs                                7.4G     0  7.4G   0% /dev/shm
    tmpfs                                7.4G     0  7.4G   0% /sys/fs/cgroup
    /dev/vda15                            99M  3.6M   95M   4% /boot/efi
    /dev/mapper/LVMVolGroup-DATA_VOLUME  138G   17G  114G  13% /mnt/data
    tmpfs                                1.5G     0  1.5G   0% /run/user/0

Even if there are 2GB of free space on / , it shows that the filesystem is at 100% of usage, and I can't install new packages because it tells me there's no space left on device. Besides, if I type sudo du -sh /* | sort -rh | head -15 the result is:

17G /mnt
1.1G    /usr
292M    /var
208M    /root
139M    /run
49M /boot
48M /tmp
32M /etc
28K /home
16K /lost+found
12K /anaconda-post.log
4.0K    /srv
4.0K    /opt
4.0K    /media
0   /sys

So it seems that there are no big files filling up the disk, and the sum of the sizes of the directories is not even equal to 44GB.

Additional info: the only service running on the server is Jenkins, but its home is under /mnt/data/jenkins.

How can I solve the problem?



Solution 1:[1]

Found the solution. The problem was related to some deleted files kept open by Jenkins. Restarting the service the problem was solved.

Solution 2:[2]

Found the solution. The problem was related to cache. Restarting the service/server the problem was solved

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 SegFault
Solution 2 Kiran Soni