>> A while back I was having networking issues.  I eventually tried
>> drastically lowering the MTU of all the systems onsite and the issues
>> disappeared.  I always thought the issue was due to the MTU on our
>> modem/router.  Today I read that AT&T DSL requires a 1492 MTU so I
>> increased the MTU of our systems up to 1492 and haven't had any
>> issues.  Do certain ISPs require you to change the MTU of your entire
>> network, or is this likely due to our AT&T modem/router itself?
> Are you using tunnels or a firewall that blocks related "icmp
> fragmentation needed" packets?

I have this in shorewall/rules:

ACCEPT  all  all  icmp  -  -  -  10/sec:20

Which I believe accepts all icmp packets but throttles them to 10/sec
to avoid being flooded.  Is that OK?

> Please also try to find out if you're experiencing packet loss. If
> fragmented packets cannot be reassembled due to some packets lost, you
> will probably find connections freezing or going really slow.

I will watch the output of ifconfig today to see if there are any RX
or TX errors.

- Grant

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