[c-nsp] 6500 admin shuts a new vlan if it has the same IP as a down vlan.

[Drew Weaver]

Sorry for the late response,

You cannot un-shut the new VLAN until you remove the downed VLAN completely.

When we create the new VLAN we do 'no shut' and it gives an error about an overlap.

I'm doing all of this via scripts; so if the IP I am assigning isn't in the routing table and it isn't assigned in our database then that means I have no way of knowing that it's still pegged to a long forgotten vlan.

I'm almost certain that this is 'newer' functionality, like SXI5+

Does anyone know if there is a way to disable it?

Thanks,
-Drew




-----Original Message-----
From: Peter Rathlev [mailto:peter at rathlev.dk] 
Sent: Monday, December 17, 2012 12:54 PM
To: Drew Weaver
Cc: cisco-nsp at puck.nether.net
Subject: Re: [c-nsp] 6500 admin shuts a new vlan if it has the same IP as a down vlan.

On Mon, 2012-12-17 at 12:34 -0500, Drew Weaver wrote:
> On a 6500 we use for lab/testing/dev if we create a new vlan with an 
> IP address that is the same as another VLAN on the device the box will 
> admin shut the new VLAN.

Our 6500s have alway put newly created SVIs in the shutdown state. We need to manually "no shutdown" them. This is different from e.g. 3560 but the 4500 does so too.
> 
> I understand it doing this if the existing VLAN is UP and maybe in 
> certain circumstances if the existing VLAN is down but is there any 
> way to disable this?

Why not just issue a "no shutdown" together with the commands that create the interface? Or is this about something else?

I actually prefer the interfaces to be administratively shutdown on creation; this makes it easier to avoid interfaces with incomplete configuration in production.

--
Peter