[CentOS] Re: Sendmail and pmtu discovery

Sean Carolan scarolan at gmail.com
Tue Oct 14 18:59:42 UTC 2008

Thanks for the information.  If I understand this correctly, the
client would have to convince the owner of each and every router hop
along the way to disable PMTU discovery if he insists on dropping all
ICMP packets?

And Scott hit the nail on the head with this comment:

> Sometimes you can't be so hard headed when you are dealing with customers. You
> usually are trying to get them to give money to YOU, not your competitor.

> If I told my customers that "It is your problem", I would no longer have
> customers to worry about!

If you've ever dealt with with one of these paranoid Mordac-type
security managers you know exactly what I'm talking about.  In our
case the path of least resistance was to disable pmtu discovery, and
tell the customer that we've done all we possibly can to alleviate the
issue on our end.  Hopefully they come to their senses and allow ICMP
packets like every major ISP and mail provider on the Internet.

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