[c-nsp] Migration from vlan 1 for core.

[Phil Mayers]

Jeff Crowe wrote:
> Hi all,
> 
> I am planning on migrating a legacy network that utilizes VLAN 1 on Cisco
> devices for it's core network to another VLAN ID (100 in this case).
> 
> Is there any gotcha's that I should be aware of?  All the switches and
> routers have IP addresses that reside in vlan 1, so this may cause me some
> concern and grief...


Well, you'll need to move the "int Vlan1" config of course.

You say you're on a "Cisco devices" network, but it's worth mentioning 
anyway... One weirdie about Cisco VLAN1 is that, using PVST, the 
instance that runs in VLAN number 1 (and vlan number 1 ONLY) emits both 
802.1d/w PDUs and PVST PDUs and therefore will interact with non-PVST 
devices.

Can be useful or horrible.