OPNsense Forum

English Forums => 25.7, 25.10 Series => Topic started by: TJL on November 21, 2025, 05:48:34 PM

Title: Decoding "detailed rule info" screen
Post by: TJL on November 21, 2025, 05:48:34 PM
I am attempting to use a Watchguard SSL VPN client to connect remotely.  Clarification: I am using a computer behind a OPNsense firewall connecting to a computer behind a Watchguard firewall.  I didn't get a clean copy before I upgraded to 27.7.7_4.  The vpn client worked before the latest upgrade.  As I read the online instructions, I found the "rid" link on the "detailed rule info" screen should point to the rule of why my vpn connection is being blocked.  On a rule that "worked" (unrelated to this issue), I click on the rid link and it brings be Firewall:Rules:Advance screen.  I don't see why I go to this screen since there are no rules.  In my case, I click on the rid link, OPNsense opens a new window (like the one that works), but then immediately closes the window.
Here is a copy of the rule info screen:
__timestamp__   2025-11-20T21:54:22-06:00
ack   897488549
action    [block]
anchorname   
datalen   0
dir    [in]
dst   external IP
dsthostname   
dstport   443
ecn   
id   48471
interface   vtnet0
ipflags   DF
ipversion   4
label   Default deny / state violation rule
length   40
offset   0
protoname   tcp
protonum   6
reason   match
rid   02f4bab031b57d1e30553ce08e0ec131
rulenr   11
seq   431912277
src   internal IP
srchostname   
srcport   64022
status   2
subrulenr   
tcpflags   RA
tcpopts   
tos   0x0
ttl   128
urp   0

I think I sanitized the screenshot.  I first thought the rulenr was the rule number, but the rules that allow access show a value of 94, but I don't think I have that many rules, unless they are counting all rules for all interfaces.  As far as I can tell, going to other HTTPS sites are working as expected.

Will someone explain how to read this page to see what rule is causing the vpn to fail?

Thanks.
Title: Re: Decoding "detailed rule info" screen
Post by: pfry on November 22, 2025, 02:46:07 AM
Quote from: TJL on November 21, 2025, 05:48:34 PM[...]I click on the rid link, OPNsense opens a new window [...], but then immediately closes the window[...]

Sounds like an automatic rule. Those don't have configuration pages.

As for the rule info, that's the automatic default deny ("label  Default deny / state violation rule"). It looks rather like you don't have an appropriate pass rule on vtnet0 ("interface  vtnet0") for HTTPS ("dstport  443"), but the TCP flags ("tcpflags   RA") indicate a reset/reject (TCP term/firewall term, respectively), from the client (not the server, where it might be the Watchguard). If in fact you have an appropriate pass rule for HTTPS on vtnet0, this indicates a TCP RA packet outside of an established session; if you do not, it's an odd client behavior, as you can't start a session with a reset. Circumstances where you normally see this include multiple network paths (where at least one bypasses the firewall), junk from the Internet (not normally in this direction), or when the firewall state table is cleared. I suppose if you used the client HTTPS request to set up the tunnel, delay and/or packet loss could upset the client, and a reset might appear to the firewall to be outside of an established session. This circumstance should be temporary. I haven't actually set up a tunnel in about 15 years (and never on OPNsense), so I'm a bit behind the times.

By the way, you can locate the rules by rid under "Firewall: Diagnostics: Statistics" -> "rules" -> "filter rules" (the "label" field, not the same as the text label/Description).