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> The hotel's router/modem may be using PPPoE to authenticate with their ISP, |
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> which has a larger header size and requires an MTU of 1492 (1464+28=1492) |
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> |
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> So, although your NIC is configured to the full ethernet MTU size, the router |
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> drops the size down to 1492 to be able to squeeze it out through the ISP's |
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> network. That's all good and proper and will not cause the timeout problem |
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> you have been experiencing. |
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|
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OK, does PMTUD lower the outgoing packet size on my system due to the |
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hotel router's lower MTU or does the hotel router itself fragment my |
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1500 byte packets in order to send them out? Just curious. |
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|
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> Have you checked that the firewall at your server is not set to drop all ICMP |
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> packets and that you don't have something like this set up on it: |
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> |
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> net.ipv4.icmp_echo_ignore_all = 0 |
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> |
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> (use sysctl to check) |
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|
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I get this which looks OK: |
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|
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# sysctl -a|grep icmp_echo_ignore_all |
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net.ipv4.icmp_echo_ignore_all = 0 |
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|
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Nikos mentioned in the other thread that I may need to configure ICMP |
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on my server's modem/router which I will be able to try tomorrow. |
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|
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- Grant |
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