How to Quickly Identify and Resolve Disk Space Exhaustion on Linux

Most common alerts are memory or CPU, but disk alerts can also occur. When a disk full alert appears, first verify it with df -Hl to see which partition is full.

How to Locate Large Disk Space Consumers

To locate large directories, run du -hs at the root, or use du -d 2 or du --max-depth=2 combined with grep and sort -nr to filter big directories.

du -h -d 2 | grep [GT] | sort -nr
du -h --max-depth=2 | grep [GT] | sort -nr

For faster results, the find command can directly locate files larger than 1 GB:

find / -type f -size +1G -exec du -h {} \;

Inconsistent Disk Space Reports

If the size reported by du or find differs from df, it may be due to deleted files that still hold space. Use lsof +L1 to list such files.

lsof +L1

Often a deleted log file still occupies dozens of gigabytes; restarting the related service (e.g., Tomcat) releases the space.

System-Reserved Disk Space

Sometimes the used and available space reported by df does not sum to the total because the system reserves a percentage (default 5 %) for the root user. Adjust the reserved space with tune2fs -m 1 /dev/vda1 to keep only 1 GB.

tune2fs -m 1 /dev/vda1