Subject: Re: down interfaces, link detection, and connected routes
To: Miles Nordin <carton@Ivy.NET>
From: Jonathan Stone <jonathan@dsg.stanford.edu>
List: tech-net
Date: 01/18/2005 16:55:28
In message <oq7jma9s8u.fsf@castrovalva.Ivy.NET>,
Miles Nordin writes:


>for me, just so long as whatever gets done, the whole system with
>quagga and dhclient and crufty ifwatchd scripts and whatever else
>watches link-detect doesn't cause open TCP connections to get
>instantly shut down when link detection is lost like on Windows ExPee,
>I'm happy.

"What he said".

Thinking about laptops here, I really, *really* don't want to lose
my TCP connections if TCP generates an ACK or retransmit whilst I
disconnect one card (e.g., pull out Ethernet cable), then reconnect
another NIC.  Or whatever.

If you do want to make the kernel auto-remove routes, please consider
adding a sysctl knob which controls router-style behaviour (drop
routes if lking down) versus end-host behaviour (keep routes even if
link is dropped).