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    How change NIC MTU to 9000?

    General pfSense Questions
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    • JKnottJ
      JKnott
      last edited by

      Incidentally, here's something about a research network in Ontario, called "Orion". It's part of the CANARIE network that connects Canada and is in turn connected to similar networks around the world. This is a second Internet that is built to support up to 9000 MTU.

      PfSense running on Qotom mini PC
      i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
      UniFi AC-Lite access point

      I haven't lost my mind. It's around here...somewhere...

      1 Reply Last reply Reply Quote 1
      • JKnottJ
        JKnott @JKnott
        last edited by

        @jknott said in How change NIC MTU to 9000?:

        The trend is to not fragment. That's manatory on IPv6 and IPv4 is moving that way. If the DF flag is set, the router is supposed to send an ICMP error message back to the source, specifying the maximum supported MTU.

        One thing I've noticed is Linux sets DF for TCP, UDP and ICMP. Windows only does for TCP.

        PfSense running on Qotom mini PC
        i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
        UniFi AC-Lite access point

        I haven't lost my mind. It's around here...somewhere...

        1 Reply Last reply Reply Quote 0
        • yon 0Y
          yon 0
          last edited by

          @tim-mcmanus said in How change NIC MTU to 9000?:

          如果它是系统之间的一堆网络流量或消息,你真的需要高MTU吗?应仔细检查数据库流量,以确定您是否在服务器之间移动了大量数据。它可能是微小的数

          ubuntu can easy setup it, but i don't know the Pfsense how do it. i use these server for BGP transit, so need fast network

          and by the way, i have test setup the txqueuelen 10000 config, helpful fast network speed. test in ubuntu and openvpn.

          but the pfsense has like this txqueuelen setup ?

          1 Reply Last reply Reply Quote 0
          • stephenw10S
            stephenw10 Netgate Administrator
            last edited by

            So what have you tried that doesn't work? You should just be able to set the interface MTU in the gui.

            Steve

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            • JKnottJ
              JKnott
              last edited by

              I just tried setting the MTU in the GUI and found it works. Here's what ifconfig shows for the interface before I changed it:

              em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
              options=209b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC>
              ether 90:e2:ba:4d:d6:b3
              hwaddr 90:e2:ba:4d:d6:b3
              inet6 fe80::92e2:baff:fe4d:d6b3%em0 prefixlen 64 scopeid 0x2
              inet6 fd48:1a37:2160:4::1 prefixlen 64
              inet 172.16.4.1 netmask 0xffffff00 broadcast 172.16.4.255
              nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
              media: Ethernet autoselect
              status: no carrier

              And after

              em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 9000
              options=209b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC>
              ether 90:e2:ba:4d:d6:b3
              hwaddr 90:e2:ba:4d:d6:b3
              inet6 fe80::92e2:baff:fe4d:d6b3%em0 prefixlen 64 scopeid 0x2
              inet6 fd48:1a37:2160:4::1 prefixlen 64
              inet 172.16.4.1 netmask 0xffffff00 broadcast 172.16.4.255
              nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
              media: Ethernet autoselect
              status: no carrier

              As you can see, the MTU changed from 1500 to 9000.

              PfSense running on Qotom mini PC
              i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
              UniFi AC-Lite access point

              I haven't lost my mind. It's around here...somewhere...

              yon 0Y 1 Reply Last reply Reply Quote 0
              • yon 0Y
                yon 0 @JKnott
                last edited by

                @jknott ..

                i have try setup in interfaces.php?if=opt3 but it not work. still MTU is 1500

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                • stephenw10S
                  stephenw10 Netgate Administrator
                  last edited by

                  Ok, we are going to need to see the opt3 config section and the ifconfig output for that interface. And any logs you have showing the change or any errors.

                  Steve

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                  • yon 0Y
                    yon 0
                    last edited by

                    @stephenw10
                    alt text
                    now i have try setup LAN nic change to MTU 9000, but still show 1500 MTU no log show.

                    alt text

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                    • GrimsonG
                      Grimson Banned
                      last edited by

                      From the FreeBSD manual at: https://www.freebsd.org/cgi/man.cgi?query=re&sektion=4&manpath=FreeBSD+11.1-RELEASE

                      The 8169, 8169S and 8110S also support jumbo frames, which can be configured via the interface MTU setting. The MTU is limited to 7422, since the chip cannot transmit larger frames. Selecting an MTU larger than 1500 bytes with the ifconfig(8) utility configures the adapter to receive and transmit jumbo frames.

                      So check what kind specific Realtek chipset you have, but 9000 will simply not work with crappy hardware like this.

                      yon 0Y 1 Reply Last reply Reply Quote 0
                      • yon 0Y
                        yon 0 @Grimson
                        last edited by

                        @grimson

                        i have try intel NIC still the same wrong.

                        1 Reply Last reply Reply Quote 0
                        • stephenw10S
                          stephenw10 Netgate Administrator
                          last edited by

                          I would also guess an re issue there. Can you set the MTU from the CLI?:

                          [2.4.4-DEVELOPMENT][root@apu.stevew.lan]/root: ifconfig re2 mtu 9000
                          [2.4.4-DEVELOPMENT][root@apu.stevew.lan]/root: ifconfig re2
                          re2: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 9000
                          	options=82098<VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,WOL_MAGIC,LINKSTATE>
                          	ether 00:0d:b9:37:30:12
                          	hwaddr 00:0d:b9:37:30:12
                          	inet 192.168.35.1 netmask 0xffffff00 broadcast 192.168.35.255 
                          	inet 19.168.35.254 netmask 0xffffff00 broadcast 19.168.35.255 vhid 1 
                          	inet6 fe80::1:1%re2 prefixlen 64 scopeid 0x3 
                          	nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
                          	media: Ethernet autoselect (none)
                          	status: no carrier
                          	carp: INIT vhid 1 advbase 1 advskew 0
                          

                          Steve

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                          • yon 0Y
                            yon 0
                            last edited by

                            i had try do that before, now i have upgrade PF 2.4.3 to 2.4.4, but i can't open lan gateway webGUI, i can ping gateway ip and network work, why i can't open webGUI. i need waiting for fix this and then try setup MTU again.

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