two interfaces one subnet

Dan White dwhite at
Mon May 11 16:31:31 CDT 2009

Chris Meidinger wrote:
> Hi,
> 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 find 
> 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.

If your goal is to achieve redundancy or to increase bandwidth, you can 
bond the interfaces together - assuming that you have a switch / switch 
stack that supports 802.3ad.

Then you could assign multiple IPs to the bonded interface without any 
layer 3 messyness.

- Dan

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