while I was collecting some logs for support via V&R Console running on my laptop I noticed that the system partition of our Veeam backup server ran out of space. After checking the Veeam server I noticed that Veeam obviously caches data in temp folder of the account that is running the backup service (e.g. C:\Users\veeam_svc\AppData\Local\Temp\VeeamLogs_2139896eeaee4d4f9fb10fbf615d109f\2017-04-10T101833_VeeamBackupLogs) when collecting log files. If I collect log files via a console running on Backup Server directly it is not cached in temp folder but rather cached in the log directory directly. I couldn't find any hint in documentation or forum that log is cached in service account temp folder when not using console on backup server.
Ok, you should always have enough free space on system partition but we have quite extensive logs and I wouldn't have expected that creating logs files fills up a disk with serveral gigs of free space.
I would suggest a hint when collecting log files via remote console (perhaps when starting log collection dialog) and/or redirect log caching via reg key.