[CentOS] Sendmail and pmtu discovery

David Dyer-Bennet dd-b at dd-b.net
Tue Oct 14 14:58:04 UTC 2008

On Tue, October 14, 2008 09:31, Kai Schaetzl wrote:
> Sean Carolan wrote on Tue, 14 Oct 2008 08:13:34 -0500:
>> My mail logs are showing that customers who specifically disallow ICMP
>> traffic have many "Connection Reset" entries in our logs:
> Could somebody explain why ICMP might play a role in mail delivery?

ICMP is involved in IP routing, including MTU discovery, announcing failed
connections, and so forth.  Email is delivered over IP.  QED.

David Dyer-Bennet, dd-b at dd-b.net; http://dd-b.net/
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