The disk space used by Linux does not match the display space.

The size and display of Linux disk space are inconsistent. operator told me that the disk space of XX server is insufficient. Let me help solve the problem. Immediately go to ssh, df-TH to see If 99% is used. All right, switch to the/directory, and the du-sh * usr accounts for 1.7 GB. The maximum folders of the others cannot exceed 300 MB, which means more than 2 GB. Du collects statistics on hidden files, so it is definitely not a problem to hide files, use this command to try lsof | grep delete rsyslogd 1294 root 4u REG 253,0 1963708027 186990/var/log/secure (deleted )............... ........ okay, that's it! The secure file was deleted without stopping rsyslogd, so the space was not released. Service rsyslogd restart to continue df-TH all OK.