OPNsense Forum

English Forums => 25.7, 25.10 Series => Topic started by: Jose on November 15, 2025, 06:48:32 PM

Title: Transparent Filtering Bridge config question
Post by: Jose on November 15, 2025, 06:48:32 PM
Hello, I'm really sorry if this was asked previously but I have some specific question regarding a typical Transparent Filtering Bridge configuration.

I was using OPNsense for several years without any issues so far, however I've recently switched from a standard setup to the Transparent Filtering Bridge mode because switched from DSL to an CGNAT/ISP, so I have some questions in regards some setting which typically differs from the OPNsense TFB how-to documentation (https://docs.opnsense.org/manual/how-tos/transparent_bridge.html)

This is my current TFB setup(IPv6 is disabled):

Interfaces: [WAN] -> igb0
  IPv4 Configuration Type: DHCP (It was: NONE)
  IPv6 Configuration Type: NONE (It was: DHCPv6)

Interfaces: [LAN] -> igb1
  IPv4 Configuration Type: NONE
  IPv6 Configuration Type: NONE (It was: Track Interface)

Interfaces: [TFB] -> igb0 + igb1
  IPv4 Configuration Type: NONE
  IPv6 Configuration Type: NONE

Interfaces: [ADM] -> vtnet0
  IPv4 Configuration Type: Static IPv4
  IPv6 Configuration Type: NONE

My question is if the above TFB configuration looks acceptable since I had set the IPv4 to DHCP on the [WAN] interface, otherwise OPNsense is unable to be upgrade as expected since there's no route to host.

OPNsense and zenarmor how-to's both specify to set the IPv4's to NONE but in my case I had to set it, the TFB rules seems to work as intended however is there any security implication leaving the [WAN] IPv4 set to DHCP alway plus the required rule to "Allow All" in such IF?

I could disable and set it back to NONE after OPNsense upgrades and reboot but that is a bit of a hassle.

PS the [ADM] interface is only for local administration, also sorry as I've push Post instead Preview while writing.

Regards
Title: Re: Transparent Filtering Bridge config question
Post by: Patrick M. Hausen on November 15, 2025, 07:03:51 PM
What are your specific questions? Just go ahead and ask them ;-)

You have read the documentation (https://docs.opnsense.org/manual/how-tos/transparent_bridge.html) on transparent filtering bridge?
Title: Re: Transparent Filtering Bridge config question
Post by: Jose on November 15, 2025, 07:16:26 PM
Quote from: Patrick M. Hausen on November 15, 2025, 07:03:51 PMWhat are your specific questions? Just go ahead and ask them ;-)

You have read the documentation (https://docs.opnsense.org/manual/how-tos/transparent_bridge.html) on transparent filtering bridge?

Hi Patrick, I've pushed wrong buttons while writing, but posted them already.

Regards