I need to find out what's contributing to the disk usage on a specific filesystem (/dev/sda2):$ df -h /Filesystem            Size  Used Avail Use% Mounted on/dev/sda2              96G   82G  9.9G  90% /I can't just do du -csh / because I have many other filesystems mounted underneath /, some of which are huge and slow:$ df -hFilesystem            Size  Used Avail Use% Mounted on/dev/sda2              96G   82G  9.9G  90% //dev/sdb1             5.2T  3.7T  1.3T  76% /disk3/dev/sda1              99M   18M   76M  20% /boottmpfs                  16G  4.0K   16G   1% /dev/shmnfshome.XXX.net:/home/userA                      5.3T  1.6T  3.5T  32% /home/userAnfshome.XXX.net:/home/userB                      5.3T  1.6T  3.5T  32% /home/userBHow can I retrieve disk usage only on /dev/sda2? None of these work:Attempt 1:$ du -csh /dev/sda20       /dev/sda20       totalAttempt 2:$ cd /dev/sda2/cd: not a directory: /dev/sda2/
Disk usage on a specific filesystem
filesystems;mount;disk usage
Use the -x (single file system) option:du -cshx /This instructs du to only consider directories of / which are on the same file system.