Subject: Ignoring ICMP redirects when net.inet.ip.forwarding = 1 ?
To: None <>
From: Jeff Rizzo <>
List: tech-net
Date: 11/13/2001 14:55:50
Browsing through the mailing list archives, there seemed to be some
discussion about a year and a half ago regarding the treatment of
ICMP redirects, and my reading of the thread led me to believe that
it had been decided that if a box is a router (ip forwarding is on),
then redirects should be ignored.  Is this the case?

I have some boxes of 1.5.1-era vintage with ip forwarding enabled, which
definitely seem to be honouring ICMP redirects.  In fact, they create
"dynamic" routes which never disappear.  :-(  

A quick browse through sysctl shows:

net.inet.ip.redirect = 1
net.inet6.ip6.redirect = 1
net.inet6.icmp6.rediraccept = 1
net.inet6.icmp6.redirtimeout = 600

...which leads me to believe that this behaviour is settable under IPv6,
at least, but not v4.  Is this the case?  What are my options
here for getting the "correct" behaviour, or at least getting routes
which time out?  :)


Jeff Rizzo