two interfaces one subnet - SOLVED
cmeidinger at sendmail.com
Mon May 11 17:00:52 CDT 2009
On 11.05.2009, at 23:39, Mike O'Connor wrote:
> :This is a pretty moronic question, but I've been searching RFC's on-
> :and-off for a couple of weeks and can't find an answer. So I'm hoping
> :someone here will know it offhand.
> :I've been looking through RFC's trying to find a clear statement that
> :having two interfaces in the same subnet does not work, but can't
> :it that statement anywhere.
> :The OS in this case is Linux. I know it can be done with clever
> :routing and prioritization and such, but this has to do with vanilla
> :config, just setting up two interfaces in one network.
> :I would be grateful for a pointer to such an RFC statement, assuming
> :it exists.
> RFC1122, Section 188.8.131.52 explicitly says this IS a legal config
> from an IP perspective:
> 3.3.4 Local Multihoming
> 184.108.40.206 Introduction
> A multihomed host has multiple IP addresses, which we may
> think of as "logical interfaces". These logical interfaces
> may be associated with one or more physical interfaces, and
> these physical interfaces may be connected to the same or
> different networks.
> There are other considerations here -- OS, link-layer, etc.
> Obviously, you want to do such things with care. But simply
> from a "standards" perspective, it's ok. There are a lot of
> hosts that historically didn't have enough RFC1122 compliance
> to make such configurations problematic (e.g. section 220.127.116.11
> and multiple default route support vs. old BSD IP stacks) but
> that doesn't invalidate the standards.
This is what I (wasn't) looking for, but was destined to find. I'll
look for other arguments against the practice.
And again, because I didn't say it before: Thanks for the pointer!!
This is just what I was looking for to stop looking.
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