[c-nsp] Subnetting problem

Ryan Wilkins ryan at deadfrog.net
Thu Oct 6 15:36:31 EDT 2011


On Oct 6, 2011, at 2:22 PM, Joseph Mays wrote:

> It feels strange to be asking a question about something as simple as a subnet here, but I'm honestly not sure what's going on in this case. Probably something simple.
> 
> As you can see from the following set of commands, the router is fine with breaking the following addresses up into /30's, but not fine with the aggregate of the two routes into a /29.
> 
> gw1.armplc(config)#ip route 216.24.2.4 255.255.255.252 216.24.0.54
> gw1.armplc(config)#no ip route 216.24.2.4 255.255.255.252 216.24.0.54
> gw1.armplc(config)#ip route 216.24.2.8 255.255.255.252 216.24.0.54
> gw1.armplc(config)#no ip route 216.24.2.8 255.255.255.252 216.24.0.54
> gw1.armplc(config)#ip route 216.24.2.4 255.255.255.248 216.24.0.54
> %Inconsistent address and mask
> 
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216.24.2.4 is not the network address in this case for a /29 (.248) netmask.  216.24.2.0 is the network address for that mask.
The proper statement would be "ip route 216.24.2.0 255.255.255.248 216.24.0.54"

Regards,
Ryan Wilkins





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