I just got notification that I am running out of root diskspace.

LinuxMint Cinnamon 18.0, fully updated as of a few minutes ago.
750GB HDD
/30 GB - 91.2% full
Swap 4 GB
Home 716 GB - 28.5% full

Why is there so much stuff in / ?

I created a large / because K3b would not find tmp and reported it had run out of diskspace in / when it was normal size. (I had originally created a separate large tmp so that I could copy and burn 8.5 GB DVD's.

$ ls -fal
total 2432
drwxr-xr-x 5 tom root 4096 Dec 7 2016 home
drwxr-xr-x 23 root root 4096 Jan 23 14:42 .
drwx------ 9 root root 4096 Nov 25 13:16 root
drwxr-xr-x 3 root root 12288 Jan 23 17:17 boot
drwxr-xr-x 10 root root 4096 Jun 28 2016 usr
drwxr-xr-x 23 root root 4096 Jan 23 14:42 ..
drwxr-xr-x 3 root root 4096 Oct 26 2016 media
lrwxrwxrwx 1 root root 30 Jan 10 11:58 vmlinuz.old -> boot/vmlinuz-4.4.0-109-generic
drwxr-xr-x 2 root root 12288 Jan 17 08:30 bin
drwxr-xr-x 20 root root 4220 Jan 24 09:00 dev
lrwxrwxrwx 1 root root 30 Jan 23 14:42 vmlinuz -> boot/vmlinuz-4.4.0-112-generic
drwxrwxrwt 18 root root 4096 Jan 24 09:39 tmp
drwxr-xr-x 11 root root 4096 Jun 28 2016 var
drwxr-xr-x 2 root root 4096 Jun 28 2016 mnt
lrwxrwxrwx 1 root root 33 Jan 23 14:42 initrd.img -> boot/initrd.img-4.4.0-112-generic
drwxr-xr-x 149 root root 12288 Jan 24 09:10 etc
drwxr-xr-x 2 root root 12288 Jan 17 08:30 sbin
drwxr-xr-x 2 root root 4096 Oct 18 2016 cdrom
drwxr-xr-x 2 root root 4096 Jan 17 06:29 lib64
drwxr-xr-x 3 root root 4096 Nov 4 2016 opt
dr-xr-xr-x 200 root root 0 Jan 19 17:52 proc
drwx------ 2 root root 16384 Oct 18 2016 lost+found
drwxr-xr-x 2 root root 4096 Jun 28 2016 srv
-rw------- 1 root root 19480576 Aug 2 21:30 core
drwxr-xr-x 26 root root 4096 Jan 17 06:29 lib
dr-xr-xr-x 13 root root 0 Jan 19 17:52 sys
lrwxrwxrwx 1 root root 33 Jan 10 11:58 initrd.img.old -> boot/initrd.img-4.4.0-109-generic
drwxr-xr-x 33 root root 1120 Jan 24 09:10 run

What does not belong in / ?


What to do?

I suggest you give us some more information about your system. Run the following command from a terminal:

From the information you have provided, your talking a 30gb 'root' partition.

4gb SWAP partition and a 716gb 'home' partition.

Have you installed a lot of software, that was not installed by default?

1 members found this post helpful.

$ lsblk -f
NAME FSTYPE LABEL UUID MOUNTPOINT
sda
├─sda1
├─sda5 ext4 a10e215d-00f5-4218-956b-ecc8ed6fba1f /
├─sda6 swap 093409f7-f0af-4c8f-a22c-5a3b3816a364 [SWAP]
└─sda7 ext4 9983149b-3a05-462b-96a6-939625e6c7b6 /home
sr0

Run this to see what are biggest consumers. Use [code] tags when posting output

This is a core dump file and can be safely deleted. Does your computer crash often?

Note the use of "-x" ...

Ouch... completely missed the -x, previous post corrected.

$ sudo du / -xh | sort -hr | head -n 15
25G /
8.9G /usr
7.7G /lib
7.4G /lib/modules
6.5G /var
5.8G /var/cache
5.7G /var/cache/apt
5.6G /var/cache/apt/archives
4.3G /usr/src
2.6G /usr/lib
1.9G /usr/share
1.8G /boot
1.1G /usr/lib/x86_64-linux-gnu
545M /var/lib
374M /usr/share/icons

Run the following command to reclaim all the space in bold above:

You're still using more space than would be expected however so also look elsewhere e.g. "core" mentioned earlier.

/ $ sudo apt-get clean
/ $ clean
No command 'clean' found, did you mean:
Command 'pclean' from package 'pbuilder-scripts' (universe)
Command 'clear' from package 'ncurses-bin' (main)
Command 'uclean' from package 'svn-buildpackage' (universe)
clean: command not found

No it does not.

Can I comment that out?

Out of interest, why did you try and run a second command called clean? The first command sudo apt-get clean should have worked.

Run the following to check that it has worked:

Because I did not get any feedback from running / $ sudo apt-get clean. I was expecting to see a download of a program "clean" like I usually do when I run apt-get.

man clean
No manual entry for clean

What is clean? Should I have expected to see any output after running sudo apt-get clean?

If all goes well, sudo apt-get clean does not provide any output. It removes the original deb packages which were downloaded during package installs. These are no longer needed. It is explained in man apt-get. Why were you expecting to see a program downloaded and installed when the apt-get command didn't include the word install? There is no package called "clean", or at least not relevant to this issue, as you have found out, it is a parameter used by apt-get.

OK, I ran the Disk Analyzer again. Looks like apt-get clean reduced it from 26.7 GB to 20.7 GB. Still need to loose more fat but thats a start. Will man apt-get while I am at it.