[c-nsp] Out of VLANs on a 2924XL

[Rick Kunkel]

Hello all...

In some places on our network, we're using older 2924XL's to support 
low-traffic colocated customers.  Most of these customers have a need for 
only a /30 or a /29, and there are gobs of them.  As a result, I've got a 
bunch of VLANs.

Here's the token ASCII art diagram:

  +--3550--+
  |  |  |  |
2924 |  |  |
     |  |  |
   2924 |  |
        |  |
      2924 |
           |
         2924  

The 3550 has 802.1q trunks to each 2924.  Each was in VTP server mode.  
The prob I ran into a few days ago was this...

I went into one of the 2924's to add a vlan to the vlan database, tried to 
exit, and got THIS:

> Proposed configuration has too many VLANs for this device's core memory
> resources.  Either reduce the number of VLANs proposed or use another
> VTP device to configure database.  (The latter will cause this device to
> enter TRANSPARENT mode automatically if propagated to it.)
> APPLY failed.
> Exiting....

I've since read about the 64 VLAN and 64 spanning-tree instances on this 
switch.

I mistakenly thought that VTP pruning might fix it, but apparently that 
only keeps traffic from traversing the link, not the VLAN table.

Then I thought I could do it with the "switchport trunk allowed vlan X" 
command, but that doesn't seem to do it either.  I was hoping, again, that 
i might keep those vlans from being advertised.

So I'm kinda stuck.  I SUSPECT that I can proably swing this by 
"downgrading" to VTP transparent mode and just configuring everything on 
each switch ultra-manually.  Is that possible?

Also, I did temporarily switch one to transparent mode, and all the vlans 
were still there.  Since the thing is a stand-alone now, would it be safe 
to remove them without affecting any of the other switches?

Thanks,

Rick