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>> A while back I was having networking issues. I eventually tried |
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>> drastically lowering the MTU of all the systems onsite and the issues |
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>> disappeared. I always thought the issue was due to the MTU on our |
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>> modem/router. Today I read that AT&T DSL requires a 1492 MTU so I |
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>> increased the MTU of our systems up to 1492 and haven't had any |
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>> issues. Do certain ISPs require you to change the MTU of your entire |
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>> network, or is this likely due to our AT&T modem/router itself? |
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> |
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> Are you using tunnels or a firewall that blocks related "icmp |
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> fragmentation needed" packets? |
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I have this in shorewall/rules: |
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ACCEPT all all icmp - - - 10/sec:20 |
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Which I believe accepts all icmp packets but throttles them to 10/sec |
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to avoid being flooded. Is that OK? |
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> Please also try to find out if you're experiencing packet loss. If |
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> fragmented packets cannot be reassembled due to some packets lost, you |
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> will probably find connections freezing or going really slow. |
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I will watch the output of ifconfig today to see if there are any RX |
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or TX errors. |
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- Grant |
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