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What is the best way to identify the cause of root space utilization. Even after restart my machine it is only showing 2.2G available in my machine.
What are the possibilities
# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/rhel-root 50G 48G 2.2G 96% / devtmpfs 6.8G 0 6.8G 0% /dev tmpfs 6.8G 420K 6.8G 1% /dev/shm tmpfs 6.8G 17M 6.8G 1% /run tmpfs 6.8G 0 6.8G 0% /sys/fs/cgroup /dev/mapper/rhel-home 408G 210G 198G 52% /home /dev/sda1 497M 96M 401M 20% /boot
I tried this
ncdu / and got this
9.1 GiB [ ] /usr 1.2 GiB [ ] /var 806.2 MiB [ ] /root 193.2 MiB [ ] /opt 167.5 MiB [ ] /run 70.6 MiB [ ] /boot 26.8 MiB [ ] /etc 420.0 KiB [ ] /dev 168.0 KiB [ ] /tmp 164.0 KiB [ ] open.txt 64.0 KiB [ ] .readahead . 0.0 B [ ] /proc 0.0 B [ ] /sys @ 0.0 B [ ] lib64 @ 0.0 B [ ] sbin @ 0.0 B [ ] lib @ 0.0 B [ ] bin e 0.0 B [ ] /srv e 0.0 B [ ] /mnt e 0.0 B [ ] /media 0.0 B [ ] .autorelabel
which shows that total space not exceeding apporx 13G. Still I am getting 49G as total used space.