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    Any way of getting around the VHID limit of 256

    Scheduled Pinned Locked Moved HA/CARP/VIPs
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    • X Offline
      xciter327
      last edited by

      Let's say I have 2 firewalls in HA mode. I want to have 200 "internal" interfaces. That means I need to use 200 VHID for IPv4 CARP interfaces. I could also provide the "internal" interfaces with IPv6 addressing, however I am hitting the VHID limit immediately and "IPv6 IP Alias cannot be assigned to IPv4 CARP interface"

      Option 1. - Don't do IPv6. I would really like to do IPv6. โ˜บ
      Option 2. - More firewalls. Where is the end...
      Option 3. - Have no IPv6 CARP/IP Alias, but have the primary router advertize itself with "high" priority and the backup one with "medium" priority.

      So far only option 3 looks like a possible solution, but I am not 100% sure client devices will play nice with it.

      Any suggestions are welcome.

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      • bepoB Offline
        bepo
        last edited by

        Option 4. - Make routing on a routing device or a switch.

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        • X Offline
          xciter327 @bepo
          last edited by

          @bepo said in Any way of getting around the VHID limit of 256:

          Option 4. - Make routing on a routing device or a switch.

          Yes changing the network design is definitely option 4.

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          • X Offline
            xciter327
            last edited by

            Actually You could re-use VHID as long as they are in a different/distinct Layer2 network segment. I'll test this out tomorrow

            bepoB 1 Reply Last reply Reply Quote 3
            • jimpJ Offline
              jimp Rebel Alliance Developer Netgate
              last edited by

              As long as the L2 is separate, you can use the same VHID for each interface.

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              • bepoB Offline
                bepo @xciter327
                last edited by

                @xciter327 Great idea!

                Please use the thumbs up button if you received a helpful advice. Thank you!

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                • X Offline
                  xciter327
                  last edited by

                  So I've been testing with a large number of CARP interfaces. I keep getting:

                  sonewconn : pcb 0xfffff800298220f0 Listet queue overflow. 193 already in queue awaiting acceptance(xxxxx occurrences)

                  Theoretically I can start increasing the "kern.ipc.somaxconn", but I am unsure if this is the right way.

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                  • jimpJ Offline
                    jimp Rebel Alliance Developer Netgate
                    last edited by

                    That error wouldn't be from CARP directly, but from a daemon or other socket provider on the firewall (web server, php, etc)

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                    • X Offline
                      xciter327
                      last edited by

                      I am still investigating, however currently it looks like pfctl is trying to start the firewall and failing.

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                      • X Offline
                        xciter327
                        last edited by xciter327

                        A little bit of PSA.

                        While You seem to be able to configure unlimited amount of interfaces, pFSense has major issues when the number of interfaces goes above 128. High CPU load, UI times out, DHCP does not work, CARP/Sync becomes unusable, system freezes up etc.

                        This is very much pFSense related and not a FreeBSD problem, by the looks of it.

                        To reproduce: make 200 vlans and assign them IPs, DHCP etc. If Your devices is really powerful make more. I've tested this on a Atom 2758 box.

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                        • DerelictD Offline
                          Derelict LAYER 8 Netgate
                          last edited by

                          The number of CARP VIPs and the number of interfaces are completely unrelated problems, but thanks for the note.

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