MTU issue

[scottyob]

Hi all,

Some websites are not working correctly for me.  This was the same issue I have when the MTU is not set correctly in IPv4, so I'm guessing it's the same issue.

considering values for MTU on ppp0, can anyone suggest appropriate values for ipv6?

eth0      Link encap:Ethernet  HWaddr 00:01:c0:04:3f:0a
          inet addr:10.1.1.254  Bcast:10.1.1.255  Mask:255.255.255.0
          inet6 addr: 2001:470:d:10fc::1/64 Scope:Global
          inet6 addr: fe80::201:c0ff:fe04:3f0a/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:3366777 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2985756 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1814088140 (1.6 GiB)  TX bytes:1103029844 (1.0 GiB)
          Interrupt:10 Base address:0xf800

eth1      Link encap:Ethernet  HWaddr 00:01:c0:04:4b:3d
          inet addr:10.12.1.254  Bcast:10.12.1.255  Mask:255.255.255.0
          inet6 addr: 2001:470:f459:1::1/64 Scope:Global
          inet6 addr: fe80::201:c0ff:fe04:4b3d/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:286056 errors:0 dropped:0 overruns:0 frame:0
          TX packets:409638 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:40174116 (38.3 MiB)  TX bytes:430437537 (410.4 MiB)
          Interrupt:5 Base address:0xf400

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:239 errors:0 dropped:0 overruns:0 frame:0
          TX packets:239 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:29088 (28.4 KiB)  TX bytes:29088 (28.4 KiB)

ppp0      Link encap:Point-to-Point Protocol
          inet addr:27.33.131.215  P-t-P:202.7.179.80  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1492  Metric:1
          RX packets:2099941 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1658339 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3
          RX bytes:1339735519 (1.2 GiB)  TX bytes:245288759 (233.9 MiB)

sit0      Link encap:IPv6-in-IPv4
          inet6 addr: ::10.12.1.254/96 Scope:Compat
          inet6 addr: ::27.33.131.215/96 Scope:Compat
          inet6 addr: ::127.0.0.1/96 Scope:Unknown
          inet6 addr: ::10.1.1.254/96 Scope:Compat
          UP RUNNING NOARP  MTU:1480  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

sit1      Link encap:IPv6-in-IPv4
          inet6 addr: 2001:470:c:10fc::2/64 Scope:Global
          inet6 addr: fe80::a0c:1fe/64 Scope:Link
          inet6 addr: fe80::1b21:83d7/64 Scope:Link
          inet6 addr: fe80::a01:1fe/64 Scope:Link
          UP POINTOPOINT RUNNING NOARP  MTU:1472  Metric:1
          RX packets:3442 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3600 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:1129262 (1.0 MiB)  TX bytes:333773 (325.9 KiB)

[annoyingspore]

I have read that since IP6 packets must fit in IP4, that if you are having problems, start at about 1280.