Subject: Re: PMTUD blackhole detection
To: Darren Reed <>
From: None <>
List: tech-net
Date: 05/01/2001 18:42:51
>>> 	on PR 12790, I posted a simple patch for TCP PMTUD blackhole detection.
>>> 	if there's no ack for a while, the patch will do the following:
>>What if there is no ACK, but ICMP unreachable errors that are not
>>"need fragmentation" - will they reset the timer (I think they should) ?
>	i did not change that part of the codepath.  icmp unreachables will
>	be counted, and if the count reaches maximum, the connection will
>	be terminated.

	"that part of the codepath" = TCP/IP illustrated vol 2, page 904 (27.6
	tcp_ctlinput) and page 905 (27.7 tcp_notify).