Use Find Command To Delete Old Logs
The /var/log/ folder usually will become filled up with old log files from logrotate. Here is a way with find command to clean and delete those.
Delete all files:
find /var/log -type f -delete
Delete all .gz and rotated file
find /var/log -type f -regex ".*\.gz$"
find /var/log -type f -regex ".*\.[0-9]$"
Try run command without “-delete”, to test it.