Log Files

When troubleshooting problems with your firewall, it is very likely you have to check the logs available on your system. In the UI of OPNsense, the log files are generally grouped with the settings of the component they belong to. The log files can be found here:

Live View Firewall ‣ Log Files ‣ Live View View firewall logs in realtime, smart filtering can be applied
Plain View Firewall ‣ Log Files ‣ Plain View Just the plain contents how **pf* logs into filter.log *

Note

Log files on file system: /var/log/filter.log (clog)

Live View

Live view updates itself in realtime if a rule is matched that has logging enabled or one of the global logging options is enabled under: System ‣ Settings ‣ Logging

For better troubleshooting you can provide a filter string. This filter may include regular expressions. Lets assume one logging entry as one single string without special separators.

So for just displaying packets that match DNS replies from wan to your lan clients in segment 192.168.1.0/24, you have to use:

WAN.*:53.*192.168.1

or to be even more correct

WAN.*:53.*192\.168\.1\.
WAN .* :53 .* 192.168.1.
Interface 1 or more characters first match of port 1 or more characters destination ip address