[c-nsp] Overlapping Subnet Issue - Gateway IP Resides in Vendor Assigned Public IP Range

[Tom Storey]

Could you do something like this (writing from memory, so forgive me
if this is wrong):

interface LAN
 ip address 10.0.128.66/26
!
interface T3
 ip unnumbered LAN
!
ip route 0.0.0.0 0.0.0.0 10.0.128.65 (or maybe specify the T3
interface instead of IP next hop)
!

Something similar used to work for PPP ADSL connections, maybe it
could work here too?

But I would tend to agree with most people here, ask them to assign
you a point to point subnet (heck even a /31 if they are concerned
about IP usage) and route the /26 to you.

On 9 July 2012 23:13, Spencer Barnes <spencer at ceiva.com> wrote:
> Hello,
>
> I'm trying to move to a new ISP.  Our old one provided a T3 and an external IP range.  The gateway IP they gave to us to assign to our router interface was on a different subnet than the external IPs they provided so having another interface dedicated to the external network was an easy setup.
>
> Our new ISP provided a gateway IP that is in the same subnet as the external IPs they provided for use.  The range they provided (changed for security) is 10.0.128.64/26.  They want us to assign 10.0.128.66 to our WAN interface and point all outbound traffic to 10.0.128.65.
>
> The problem with this setup is I can't dedicate another interface for the new external range because the subnets overlap.  I can change the g0/0 interface to 10.0.128.66 255.255.255.252 and assign the other interface g0/1 10.0.128.96 255.255.255.224 but then I lose a bunch of external IPs.
>
> Is there a better way to do this so I can use all the IPs in the range?
>
> Thanks in advance for any input.
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/