[c-nsp] Vlans and catalyst 2950

[nick.nauwelaerts at thomson.com]

Also check the "show vtp status" to see if none of them have their VTP
operating mode set to transparent.

// nick



> -----Original Message-----
> From: cisco-nsp-bounces at puck.nether.net 
> [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Alban Dani
> Sent: Wednesday, February 09, 2005 04:24 PM
> To: Adrian Pirciu
> Cc: cisco-nsp at puck.nether.net
> Subject: Re: [c-nsp] Vlans and catalyst 2950
> 
> 
> 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
> > > archive at http://puck.nether.net/pipermail/cisco-nsp/
> > 
> > --
> > adixor
> >
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