[SOLVED] Large hidden files in my \dump backup folder

[greavette]

Hello Team,

I backup some of my Proxmox VM's to a shared drive on a Windows server in our server room. I'm looking at the space on this drive and discovered 3 hidden files with no extension. They all begin with 'cifs' and have numbers after them. They are quite large where one of the three is over 58 GB. The Date Modified on these files are not current and are all out by either weeks or months so it doesn't appear something is writing to them daily.

I've also found some very large .DAT files that are related to one of the VM's I backup. They too are very large files and the dates on these, if I remember correctly, are around the time we had an issue with our Proxmox Host an the backup had failed. What is a .DAT file in relation to the Proxmox backup process?

Any idea what these files are and if they are part of the Proxmox backup process? I'd like to reclaim space by removing them but obviously don't want to interrupt or break the Proxmox backup process if they are removed. I have more current backups for all my VM's and my VM's disks themselves do not reside on this Windows backup server. This Windows server is purely used to store my Proxmox backups.

Any advice you can provide would be greatly appreciated.

 

[tsarya]

Can you share how you perform the backups?

 

[greavette]

Yes, we use the Proxmox backup scheduler to run our backups overnight (between 2am and 5am) on a daily basis. Proxmox will shutdown the VM and perform a full backup for us.

 

[tsarya]

The .dat file is the temporary file during backup, for instance I launched a manual backup and observed the /var/lib/vz/dump folder:

drwxr-xr-x 2 root root          3 Nov 10 19:43 vzdump-qemu-103-2017_11_10-19_43_52.tmp
-rw-r--r-- 1 root root   94449936 Nov 10 19:44 vzdump-qemu-103-2017_11_10-19_43_52.vma.dat

Once the backup job completes, you get:

-rw-r--r-- 1 root root       4838 Nov 10 19:45 vzdump-qemu-103-2017_11_10-19_43_52.log
-rw-r--r-- 1 root root 1783494744 Nov 10 19:45 vzdump-qemu-103-2017_11_10-19_43_52.vma.lzo

Now I suppose since you mentioned that the job failed, these are just "hogs" which were not removed by the scheduler.

As for the files in your Windows remote folder... I have no idea as I do not perform off-site backup to Windows shares.

 

[Denny]

tsayra is correct. Anytime a backup is interupted/fails there is the potential for these temporary files to be left. You can safely delete them.

 

[greavette]

Thank you tsarya and Denny for confirming root cause and what I can do with these orphaned files.

Very much appreciate the support.

Thank you.

 

[tsarya]

Do some manual tests and monitor both locations: the dump folder on the host machine and the Windows share.