On Aug 20, 2010, at 3:56 PM, Butch Evans wrote: > On Fri, 2010-08-20 at 13:20 -0400, Christopher Morrow wrote: >> Polling a little bit here, there's an active discussion going on >> 6...@ietf about whether or not v6 routers should: >> o be required to implement ip redirect functions (icmpv6 redirect) >> o be sending these by default > > I do not currently have an IPv6 deployment, so my input may be lacking > in real usefulness here. With IPv4, however, I have been a little > irritated at a few situations where I NEEDED this to work and it did not > (certain PIX routers come to mind here). There are risks involved with > ANY "automated" type traffic to be sure, but for my money, it SHOULD be > possible to configure every router to support the network needs. So for > my money, I'd suggest: > > * routers MUST support ip redirect > * "default" configurations irrelevant to me > > I do agree with one or two of the other posters that it should not be > within the purview of the IETF to "mandate" these defaults. Each of us > will learn the defaults of the particular gear we use and can adjust > config templates to match, given the needs of the network we are > deploying. Just my $0.02 (may be worth less than that) :-)
One of the challenges is that some vendors have a poor track-record of documenting these defaults. this means unless you frequently sample your network traffic, you may not see your device sending decnet mop messages, or ipv6 redirects :) Personally (and as the instigator in the ipv6/6man discussion) if the vendors could be trusted to expose their default settings in their configs, i would find a default of ON to be more acceptable. As their track-record is poor, and the harm has been realized in the network we operate (at least), I am advocating that as a matter of policy enabling redirects not be a default-on policy. If people want to hang themselves that's their problem, but at least they won't come with a hidden noose around their neck. - Jared
