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PATH-MTU changed during upgrade?

Posted: 31 May 2015 17:22
by rasputinlv
Does anybody know why would PATH-MTU change during code upgrade from 10r5 to 12r9.
It went from default 9182 to 2076!
Thanks an advance.

Re: PATH-MTU changed during upgrade?

Posted: 01 Jun 2015 11:56
by mivens
Listed in the release notes as resolved since 11.0R5:
When Path-MTU Discovery (PMTUD) is enabled, the system no longer ignores the peer Maximum Segment Size (MSS)
advertised during the TCP connection establishment. If the peer advertises an MSS lower than the local MSS, the system will reduce the local MSS to the lower value. [165896-MA]