[c-nsp] Problems with secondary ip address on subinterfaces

[Ed Ravin]

On Sun, Dec 17, 2006 at 12:32:28PM +0000, Paul Cairney wrote:
> I am having some odd issues with secondary IP addresses configured
> on a couple of 2821's running c2800nm-spservicesk9-mz.124-7b.bin.
...
> When these ip's are configured as the primary ip's on this
> subinterface (either standalone or with my own ip's as secondarys)
> then I can ping the providers ip's no problem (10.0.25.2 and
> 10.0.25.3) however when these address are configured as secondarys
> it doesnt want to work.

By default, ping uses the primary address of the interface as the
source IP on the ping packet.  If that IP is not reachable by your
destination, you won't get a response.

Use "ping ip DESTINATION-IP source SOURCE-IP" to use test pings
from the router.