Temporary Files directory seems unusually large, any way to safely delete or clean up?

My Temporary Files directory is 18GB, while my backups are only 2GB. Can I safely delete the temporary files, or is there a way to clean them up in UrBackup?

I have been using UrBackup in a Docker container running on Ubuntu 20.04 for about a year, doing file backups of a few small web servers (also running Ubuntu if it matters). Everything has been working great! This is on a VM hosted in Azure, and I have a 30GB OS drive attached to the VM, no separate data disk.

I recently noticed my drive has low space, which I thought was odd because the backed up files should total less than 2GB. It appears that the temporary files directory is using 18GB of space, while the actual backups show the expected sizes.

In the filesystem, I have all backups going to /media/backups. In UrBackup, I have my “Backup Storage Path” set to /backups, which is redirected to /media/backups in my Docker setup (see command below). When I do a disk space check, I get the following output:

sudo du -h /media/backups/ --max-depth 1 | sort -rh

20G     /media/backups/
18G     /media/backups/urbackup_tmp_files
1.2G    /media/backups/WordPress
637M    /media/backups/urbackup
270M    /media/backups/Meshcentral
106M    /media/backups/UniFi
4.0K    /media/backups/clients

A further look in the urbackup_tmp_files directory:

18G     /media/backups/urbackup_tmp_files/
16G     /media/backups/urbackup_tmp_files/WordPress
990M    /media/backups/urbackup_tmp_files/Meshcentral
637M    /media/backups/urbackup_tmp_files/urbackup
547M    /media/backups/urbackup_tmp_files/UniFi
4.0K    /media/backups/urbackup_tmp_files/clients

Here is the command I am using to start the container:

sudo docker run -d --restart unless-stopped --name urbackup-server-1 -v /media/backups:/backups -v /media/database:/var/urbackup -p 55413-55415:55413-55415 -p 35623:35623/udp uroni/urbackup-server

I’m not sure if I have something mis-configured, but I didn’t see anything in the settings or the manual about how to reduce the size of these temp files or get them cleared out. I know there is a “Temporary files as file backup buffer” setting but I don’t think that applies here, please let me know if that’s not the case.

I suppose I could just upgrade the hard drive to a larger size if this is considered normal behavior for UrBackup, but it just seems odd that the temp files would need to be so large. Thanks very much for any help!

Usually all tmp files are deleted on startup. Idk how it happened that you have clients in the urbackup_tmp_files directory? Maybe you could investigate a bit (look into those folders) and look into what happened?