Solution
Free up space on your root volume. See this great forum post: [How-To] Fix full OS filesystem – GUI login loop
Avoid the problem in the future
Simple – make sure your root volume doesn’t fill up.
Some options:
- Buy a large hard drive
- Make sure the server’s outbound email / notification services are functioning (and check your email)
- Login and verify the root volume has free space allocated with “df” infrequently
- Use a server monitoring service to report the disk space
- Spend a bunch of time configuring a Graphana instance at home like this or this and put it in a place where it can be observed.
Problem
When I attempted to login to my web interface for my Open Media Vault server, the screen would refresh and bring me back to an empty login screen. No fun! How am I supposed to fiddle around with Node-Red, Home Assistant and PiHole?
After running df, I found my root volume was full. Looking at the list of volumes, / was used at 100%, with 0 blocks available:
Last login: Wed Dec 14 16:46:39 2022
[email protected]:~$ df
Filesystem 1K-blocks Used Available Use% Mounted on
udev 990264 0 990264 0% /dev
tmpfs 202936 2992 199944 2% /run
/dev/sda1 72400968 68738728 0 100% /
tmpfs 1014668 0 1014668 0% /dev/shm
tmpfs 5120 0 5120 0% /run/lock
This command lists volumes and sorts to show only the top 10 volumes
[email protected]:/$ sudo du -xhd1 | sort -hr | head -n 10
65G .
42G ./sharedfolders
19G ./var
4.5G ./usr
286M ./boot
13M ./home
8.3M ./data
8.1M ./etc
3.5M ./root
1.7M ./srv
I can see that my /var directory is taking up 19 gigs.
Using the ncdu utility, /var is reportedly only taking up 4 gigs.
Looking into /var, I see what I expected- a lot of storage taken up in /logs:
ncdu 1.13 ~ Use the arrow keys to navigate, press ? for help
--- /var -----------------------------------------------------------------------------------------------
/..
. 3.4 GiB [##########] /log . 630.2 MiB [# ] /cache
. 321.7 MiB [ ] /lib
. 49.5 MiB [ ] /backups
7.3 MiB [ ] /www
. 128.0 KiB [ ] /spool..
…and /journal is responsible for most of that:
ncdu 1.13 ~ Use the arrow keys to navigate, press ? for help
--- /var/log -------------------------------------------------------------------------------------------
/.. 2.8 GiB [##########] /journal
138.0 MiB [ ] daemon.log.1
105.1 MiB [ ] daemon.log
Another culprit was docker’s filesystems:
ncdu 1.13 ~ Use the arrow keys to navigate, press ? for help
--- /var/lib/docker/overlay2 -------------------------------------------------------------------------
/.. 1.1 GiB [##########] /b6be9adc7a3ab5b180028f5a332dc5bbd71bfbaa3784fc7847bba2358b7487e9
921.3 MiB [####### ] /401f5e649ba06b0782cf425c45b5dcddeb41351339641806e7b32244c7b9d28a
916.8 MiB [####### ] /8c134dd74390b5d10719483cf40a22ae1ebbbf3ff5051555a293d95bc9af43fd
574.3 MiB [#### ]
So, I used sudo docker system prune -a -f, resulting in:
sudo docker system prune -a -f
Deleted Containers:
c9e3773f2cbb4ac7067b89bdcf1c0133b0b37c3f6ac446774070d6c754955405
40fd33305c81320dd7a5fb936e1e85042b89c34305fb4a565f97c76f14538fcf
e538f72bb3ca901d42796c9b5fa85afaa0d716dee2bcaac598448a9d63cdb30a
Deleted Images:
untagged: linuxserver/letsencrypt:latest
untagged: homeassistant/home-assistant:latest
<.. Many more entries ..>
Total reclaimed space: 7.122GB
Success!
After freeing up some disk space, I was able to login to Open Media Vault with no issues.