Log files are too big: PROPER manual log files reduction?

Hi,
Using umbrel v0.5.4 on R pi. System was stuck. Some complains about full disk. no web UI. Looks like I can log using ssh and basic linux stuff works. web UI did not work, it was like the SD card was 100% full (that was the problem) and 1 TB drive is almost full (87%) - that will be the problem. This is not proper way to log. Why we have GBs of dataaaaa used? how to do it better?

Filesystem      Size  Used Avail Use% Mounted on
/dev/root        15G   15G     0 100% /
/dev/sda1       916G  750G  120G  87% /home/umbrel/umbrel

I was able to go and delete single large file (willy nilly, without knowing if it does have some consequences)

rm /sd-root/var/log/syslog.1

that freed up almost 5GB of space. This is not correct way. There must be better way to vacuum logs, and cap them to maybe 100MB on both SSD and SD card. How to do that properly? Please advise.