Can't assign IP to interface, says subnet in use

[gmail2]

I'm using a router simulator at home and I've setup 3 routers on it - each connected directly with serial interfaces. However, on s1 of one of the routers, when I try to set the ip to 10.0.0.10/30 it says that 10.0.0.0 overlaps with serial0. The IP of serial0 is 10.0.0.1/30 - so they're 2 different subnets. Why is it saying this, I can't see anything wrong with my addressing scheme - can anybody else? I've used subnets 10.0.0.0/30, 10.0.0.4/30 and 10.0.0.8/30 on the 3 different networks between the routers and all the other are working fine but this one doesn't like the IP for some reason. Anybody got any ideas?

 

[rtfmdude]

you have 'ip classless' configured? seems like that could be it. I'm sure it's a default, but you never know...

 

[vipergg]

If you are sure the addressing is right with the correct mask on each interface it's possible it's a bug in your router simulator .

 

[gmail2]

vipergg - yea you're right it is a bug. I swapped the 2 IP's between the 2 interfaces on that subnet and it worked fine. Weird huh !!