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    RFC4638? Baby jumbo frames for PPPoE connections (MTU 1508)

    Scheduled Pinned Locked Moved General pfSense Questions
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    • M
      martin42
      last edited by

      Hi,

      Does 2.2-RELEASE support baby jumbo frames for PPPoE?  That would be great for FTTC connections in the UK.

      Many thanks!

      • Martin.
      1 Reply Last reply Reply Quote 0
      • jimpJ
        jimp Rebel Alliance Developer Netgate
        last edited by

        I believe so, there was at least one, possible more, forum thread about it in the 2.2 development board.

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        • P
          pf3000
          last edited by

          Any idea how this might work on pfSense? Simply setting the WAN MTU to 1508 doesn't work for me.

          My GPON internet does RFC 4638. I could connect and ping 1472 bytes using Openwrt BB.

          1 Reply Last reply Reply Quote 0
          • P
            pf3000
            last edited by

            I set the following:
            WAN MTU to 1500
            interfaces>PPPs>pppoe0> MTU = 1500 and MRU =1500

            Result: everything looks ok from the outside except ping.

            [2.2-RELEASE][root@pfSense.playgroup]/root: ifconfig pppoe0
            pppoe0: flags=88d1 <up,pointopoint,running,noarp,simplex,multicast>metric 0 mtu 1500
                    inet 92.98.85.45 --> 31.215.64.1 netmask 0xffffffff
                    inet6 fe80::20c:29ff:feb2:e4ab%pppoe0 prefixlen 64 scopeid 0x7
                    nd6 options=21 <performnud,auto_linklocal>[2.2-RELEASE][root@pfSense.playgroup]/root: ifconfig vmx0
            vmx0: flags=8843 <up,broadcast,running,simplex,multicast>metric 0 mtu 1500
                    options=60079b <rxcsum,txcsum,vlan_mtu,vlan_hwtagging,vlan_hwcsum,tso4,tso6,lro,rxcsum_ipv6,txcsum_ipv6>ether 00:0c:29:b2:e4:ab
                    inet6 fe80::20c:29ff:feb2:e4ab%vmx0 prefixlen 64 scopeid 0x1
                    nd6 options=21 <performnud,auto_linklocal>media: Ethernet autoselect
                    status: active
            [2.2-RELEASE][root@pfSense.playgroup]/root: route get 8.8.8.8
               route to: google-public-dns-a.google.com
            destination: default
                   mask: default
                gateway: 31.215.64.1
                    fib: 0
              interface: pppoe0
                  flags: <up,gateway,done,static>
             recvpipe  sendpipe  ssthresh  rtt,msec    mtu        weight    expire
                   0         0         0         0      1500         1         0
            [2.2-RELEASE][root@pfSense.playgroup]/root: ping -c 4 -s 1472 8.8.8.8
            PING 8.8.8.8 (8.8.8.8): 1472 data bytes
            ^C
            --- 8.8.8.8 ping statistics ---
            4 packets transmitted, 0 packets received, 100.0% packet loss
            [2.2-RELEASE][root@pfSense.playgroup]/root: ping -c 4 -s 1462 8.8.8.8
            PING 8.8.8.8 (8.8.8.8): 1462 data bytes
            1470 bytes from 8.8.8.8: icmp_seq=0 ttl=50 time=119.920 ms
            1470 bytes from 8.8.8.8: icmp_seq=1 ttl=50 time=116.631 ms
            1470 bytes from 8.8.8.8: icmp_seq=2 ttl=50 time=116.487 ms
            1470 bytes from 8.8.8.8: icmp_seq=3 ttl=50 time=116.757 ms
            
            --- 8.8.8.8 ping statistics ---
            4 packets transmitted, 4 packets received, 0.0% packet loss
            round-trip min/avg/max/stddev = 116.487/117.449/119.920/1.430 ms</up,gateway,done,static></performnud,auto_linklocal></rxcsum,txcsum,vlan_mtu,vlan_hwtagging,vlan_hwcsum,tso4,tso6,lro,rxcsum_ipv6,txcsum_ipv6></up,broadcast,running,simplex,multicast></performnud,auto_linklocal></up,pointopoint,running,noarp,simplex,multicast>
            
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            • P
              pf3000
              last edited by

              I suppose PPPoE in pfSense/FreeBSD is maximum of 1492

              Feb 6 10:36:14	ppp: mpd_wan.conf:31: Error in 'set link mtu 1500': max MTU on type "pppoe" links is 1492
              Feb 6 10:36:14	ppp: mpd_wan.conf:32: Error in 'set link mru 1500': max MRU on type "pppoe" links is 1492
              Feb 6 10:36:14	ppp: [wan_link0] Link: OPEN event
              Feb 6 10:36:14	ppp: [wan_link0] LCP: Open event
              

              More info
              Baby jumbo frames (MTU 1508) for PPPoe connections?

              1 Reply Last reply Reply Quote 0
              • N
                nietzowietzo
                last edited by

                Anyone got it working already? Just like in the UK many Fiber optic providers in the Netherlands use PPPoE and support RFC4638. So it would be great if we can get it working.

                1 Reply Last reply Reply Quote 0
                • P
                  pf3000
                  last edited by

                  I'm prepared to offer a bounty to anybody who makes this happen. Bounty thread started for those who would like to contribute
                  RFC 4638 (PPPoE 1508 MTU) - let's pitch in

                  1 Reply Last reply Reply Quote 0
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