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Sorry to double post but I should have included this info. |
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|
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mtu == 1500 for the following |
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|
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ping -s 5000 172.17.187.220 |
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|
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tcpdump run on 172.17.187.220 |
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|
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tcpdump -n -i eth0 host 172.17.187.221 |
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|
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10:17:53.618060 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:17:53.618062 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:17:53.618065 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:17:53.618095 IP 172.17.187.220 > 172.17.187.221: icmp 1480: echo reply |
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seq 4 |
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10:17:53.618099 IP 172.17.187.220 > 172.17.187.221: icmp |
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10:17:53.618100 IP 172.17.187.220 > 172.17.187.221: icmp |
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|
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now I lower the mtu |
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|
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ifconfig eth0 mtu 1492 |
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ping -s 5000 172.17.187.220 |
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|
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tcpdump run on 172.17.187.220 |
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|
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tcpdump -n -i eth0 host 172.17.187.221 |
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|
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10:20:03.185397 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:20:03.185400 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:20:03.185402 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:20:03.185433 IP 172.17.187.220 > 172.17.187.221: icmp 1480: echo reply |
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seq 4 |
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10:20:03.185436 IP 172.17.187.220 > 172.17.187.221: icmp |
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10:20:03.185438 IP 172.17.187.220 > 172.17.187.221: icmp |
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10:20:03.185440 IP 172.17.187.220 > 172.17.187.221: icmp |
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|
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So as you can see they are the same however the reply never comes back as |
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proved by this tcpdump. |
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|
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tcpdump run on 172.17.187.221 |
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tcpdump -n -i eth0 host 172.17.187.22 |
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|
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10:24:51.105366 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:24:51.105369 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:24:51.105371 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:24:51.105652 IP 172.17.187.220 > 172.17.187.221: icmp |
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10:24:52.105450 IP 172.17.187.221 > 172.17.187.220: ICMP echo request, id |
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42519, seq 3, length 1472 |
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10:24:52.105455 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:24:52.105456 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:24:52.105458 IP 172.17.187.221 > 172.17.187.220: icmp |
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10:24:52.105669 IP 172.17.187.220 > 172.17.187.221: icmp |
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10:24:53.105545 IP 172.17.187.221 > 172.17.187.220: ICMP echo request, id |
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42519, seq 4, length 1472 |
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|
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|
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|
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On 2/6/07, Brett Curtis <dashnu.mutt@×××××.com> wrote: |
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> |
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> have tried everything possible short of testing a different network card |
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> because I do not have one. I have delt with IMB support but since I run |
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> gentoo they are not much if any help at all. I compiled the drivers they |
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> provide with the same results. I tried booting from gentoo live disk.. I |
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> am |
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> running out of ideas. I have tried doing this on different network |
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> switches |
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> differnt cables... and still nothing. |
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> |
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> I can not lower the mtu on *any* on my Broadcom Corporation NetXtreme |
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> nics. |
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> I |
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> have 5 of these boxes! Same results on all. |
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> |
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> my test is this: |
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> |
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> ping -s 5000 somehost.inmy.lan |
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> |
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> works as expected. |
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> |
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> ifconfig eth0 mtu 1492 |
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> ping -s 5000 somehost.inmy.lan |
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> |
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> nothing.. and of course I set my mtu back to 1500 everything works fine. |
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> |
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> I have done this same test with machines with different nics and |
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> everything |
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> works. |
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> |
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> I am building 2.6.20 now in hopes it may fix something. |
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> |
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> Any ideas? |
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> |
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> Thanks |
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> |
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> -- |
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> |
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> Created with VIM & mutt. |
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> |
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> Our comedies are not to be laughed at. -Samuel Goldwyn |
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> |
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> |
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