5 "Advanced" networking questions

Terry Lambert tlambert2 at mindspring.com
Tue Jul 8 03:19:10 PDT 2003

Socketd wrote:
> Ok, anyway to prevent sending ICMP's when ttl = 0? Or do I need a
> firewall?

I guess you want to do this so that you can break path MTU
discovery and fail to properly exchange packets with the DF
bit set in the headers, and which don't take into account
intermediate links with smaller MTUs, like VPNs or PPPOE

What exactly are you getting from disabling ICMP, besides a
broken network connection to some systems you may wish to be
able to exchange packets with?

-- Terry

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