[c-nsp] Vlans and catalyst 2950

[Adrian Pirciu]

try creating a new vlan on the 6500 and then use sh vlan to see if it 
is created automatically on the 29xx. If not, there is a vtp 
configuration mismatch somewhere.

add some outputs of "sh vtp status" on the 6500 and 29xx if you can 
please.

Alban Dani wrote:
> Hi there,
> 
> we are using VTP. All the new Vlans are created on the 6509 which is the core.
> 
> Here is the output of the show  vlan on the cat2950:
> 
> cat2950#sh vlan id 41
> VLAN Name                             Status    Ports
> ---- -------------------------------- --------- -------------------------------
> 41   Stevens                        active    Fa0/6, Fa0/35, Fa0/46, Gi0/1
> VLAN Type  SAID       MTU   Parent RingNo BridgeNo Stp  BrdgMode Trans1 Trans2
> ---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
> 41   enet  100041     1500  -      -      -        -    -        0      0
> Remote SPAN VLAN
> ----------------
> Disabled
> Primary Secondary Type              Ports
> 
> cat2950#sh spanning-tree vlan 41
> 
> VLAN0041
>   Spanning tree enabled protocol ieee
>   Root ID    Priority    24617
>              Address     0009.b799.a680
>              Cost        28
>              Port        49 (GigabitEthernet0/1)
>              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
> 
>   Bridge ID  Priority    32809  (priority 32768 sys-id-ext 41)
>              Address     000b.fd53.9540
>              Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
>              Aging Time 300
> 
> Interface        Role Sts Cost      Prio.Nbr Type
> ---------------- ---- --- --------- -------- --------------------------------
> Fa0/35           Desg FWD 19        128.35   P2p
> Fa0/46           Desg FWD 19        128.46   P2p
> Gi0/1            Root FWD 4         128.49   P2p
> 
> Port Fa0/35 is trunked and Vlan 41 never makes it up this trunk unless
> as I have explained I put a port on cat2950 on that vlan and get  some
> traffic in it.
> 
> 
> Thanks,
> 
> Alban
> 
> On Wed, 09 Feb 2005 10:58:15 +0200, Adrian Pirciu
> <adrian.pirciu at rdsnet.ro> wrote:
> 
>>Hello
>>
>>Alban Dani wrote:
>>
>>>Hello Matthew,
>>>
>>>I also am having a very wierd issue with vlans and 2950-s.
>>>
>>>We are running pst+.
>>>We have a 6509 in the core and everytime we try to get a new vlan
>>>passed through a chain  of switches( all connected via dot1q trunks)
>>>that has a 2950 in it, it does not work. The only workaround we found
>>>so far is to go to a port on the given 2950 , set the port on the
>>>requried vlan and connect a machine to it and through some traffic.
>>>That makes the 2950 aware of  that vlan.
>>
>>a 2950 will not pass traffic for the vlans not defined in its table.
>>When you put a port in a vlan, it automatically adds this vlan to the
>>config (sh vlan) and it starts forwarding traffic for that vlan which
>>explains the behaviour you describe.
>>
>>You can use VTP if you want to have a consistent vlan database accross
>>you network. Be careful though (there are some bat things that can
>>happen, read the documentation from www.cisco.com and they are
>>described).
>>
>>
>>
>>>If this was not enough, if the vlan in question does not see traffic
>>>for a couple of days the 2950 totally forgets about it.
>>
>>I am not aware of anything resembling this behaviour. Anybody ? Does
>>the vlan apper on "sh vlan" when this happens ?
>>
>>
>>>I am wondering if you ever found a solution to your problem and if so
>>>what was it?
>>>
>>>I have upgraded to the latest IOS but it did not help.
>>
>>i'm pretty sure it is not an IOS/switch related problem.
>>
>>
>>>thanks,
>>>
>>>Alban
>>>_______________________________________________
>>>cisco-nsp mailing list  cisco-nsp at puck.nether.net
>>>https://puck.nether.net/mailman/listinfo/cisco-nsp
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>>
>>--
>>adixor
>>


--
adixor