From: Victor Cappuccio (cvictor@protokolgroup.com)
Date: Sun Aug 13 2006 - 14:53:38 ART
Dave, I know these one
Sw1#debug sw-vlan vtp ?
events vtp events
packets vtp packets
pruning vtp pruning events
redundancy vtp redundancy
xmit vtp packets transmitted
Maybe there are more, but just my 2 cents
Victor.-
-----Mensaje original-----
De: Schulz, Dave [mailto:DSchulz@dpsciences.com]
Enviado el: Domingo, 13 de Agosto de 2006 10:42 a.m.
Para: Victor Cappuccio; kwasi-ccie@comcast.net; Godswill Oletu; Tim Chan;
ccielab@groupstudy.com
Asunto: RE: trunk allowed vs pruning
After much labbing and research on this pruning/allowed issue. Here is what
I discovered......
1. VTP pruning does not affect the advertisement of the VLANs from the VTP
Server to the VTP Clients. IOW, all vlans will show up on all switches,
EVEN if the specific vlan is not allowed on the trunk, and/or, if there are
interfaces/ports configured in that specific vlan or not. Therefore, when
using VTP server/client.....ALL vlans will be advertised to all switches.
2. What VTP Pruning does do is.....As per the docCD.....
VTP pruning blocks unneeded flooded traffic to VLANs on trunk ports that are
included in the pruning-eligible list.
3. Allowing vlans on the trunk (using the switchport trunk allowed
command), will allow and disallow all traffic for any specific vlan between
switches. Test this.....
- Sw1 (Server) and Sw2 (Client).
- Disallow all vlans on the trunk between the switches.
- On the server, configure a vlan. NOTE: this vlan will show up on the
client even though it is disallowed.
- Do a show spanning command on the client and you will see that it does not
show up on the switch (even though it is "advertised" by the server).
I have not found a good debug command for vtp or to check the broadcast
traffic of the pruned (or not pruned) vlans....if anybody has this.
Dave Schulz,
Email: dschulz@dpsciences.com
-----Original Message-----
From: Victor Cappuccio [mailto:cvictor@protokolgroup.com]
Sent: Saturday, August 12, 2006 12:45 AM
To: Schulz, Dave; kwasi-ccie@comcast.net; 'Godswill Oletu'; 'Tim Chan';
ccielab@groupstudy.com
Subject: RE: trunk allowed vs pruning
Hey Dave,
I'm still struggling with that also, but I find that creating Vlans in both
switches and assign them to different ports doing pretty drawing of what
vlan should be passing the trunk, and the vlans that should not pass the
trunk is a good way to understand the situation.
A good command that helps to play around is
Sw1#test sw-vlan pruning f0/13 ?
actual Current PM value
status Current status
Sw1#test sw-vlan pruning f0/13 status
VLANs existing: 1,17,1002-1005
VLANs vtp allowed: 1,17,1002-1005
VLANs vtp pruning enabled:
Pruning currently DISABLED.
Sw1#test sw-vlan pruning f0/13 actual
VLANs existing: 1,17,1002-1005
VLANs currently allowed by PM: 1,17,1002-1005
VLANs currently pruning enabled by PM: 17
VLANs currently pruned by PM:
Pruning currently DISABLED.
(Sorry I have the lab occupied with a Customer Solution, so I could not
touch it very much)
The switchport trunk allowed vlan, is useful to allow traffic for vlans over
the trunk and if my interpretation is right this command used only when VTP
Messages are not announced (Transparent mode) or when VTP Prunning is
Disabled,
The switchport trunk pruning vlan, would remove the Vlan from the prune
elegible list, so the vlan would not be pruned automatically via VTP
Messages, and flooded traffic would cross the link to end in /dev/null (CPU
steam )
My 2 Cents
Victor.-
-----Mensaje original-----
De: nobody@groupstudy.com [mailto:nobody@groupstudy.com] En nombre de
Schulz, Dave
Enviado el: Sabado, 12 de Agosto de 2006 12:25 a.m.
Para: kwasi-ccie@comcast.net; Godswill Oletu; Tim Chan;
ccielab@groupstudy.com
Asunto: RE: trunk allowed vs pruning
I also am a bit confused on the process of the pruning function. I have
been labbing this up different ways and I can get the trunk allowed
command to work as it should. However, the pruning function on the
interface that is trunking doesn't appear to be pruned back on the
client. I still see all the vlans advertised (even though they are not
being used). I thought that the pruning would cause the vlans to not
show up in the "show vlan" list of the client. Is this not the case?
Here is my config under the port that is trunking. VTP is set for the
server and pruning is enabled..... Thoughts?
interface FastEthernet0/13
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 2-999
switchport trunk pruning vlan 2-10
switchport mode trunk
switchport nonegotiate
Dave Schulz,
Email: dschulz@dpsciences.com
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
kwasi-ccie@comcast.net
Sent: Friday, August 11, 2006 1:43 PM
To: Godswill Oletu; Tim Chan; ccielab@groupstudy.com
Subject: Re: trunk allowed vs pruning
You only need to remove vlan 8 from the prune eligible list on sw1 port
fa0/13 to solve problem 1 (switchport trunk pruning vlan remove 8).
Problem 2 is already solved by the vtp pruning that you enbaled on both
switches. You do not need to play with the vtp allowed list to solve
these 2 problems. Test it out.
-------------- Original message --------------
From: Godswill Oletu <oletu@inbox.lv>
> Tim,
>
> The solution you provided will only take care of the first task, once
VLAN 8
> is removed from the prunning eligible list of interface fa0/13, the
switch
> will continue to receive traffic for VLAN 8 regardless of local
assignment
> or not.
>
> For the second task, you have to remove VLAN 8 from the VLAN allowed
list on
> interfaces fa0/14 & fa0/15.
>
> HTH
>
> Godswill Oletu
> CCIE #16464
>
>
> ----- Original Message -----
> From: "Tim Chan"
> To:
> Sent: Friday, August 11, 2006 2:21 AM
> Subject: trunk allowed vs pruning
>
>
> > Hi all,
> >
> > I keep confusing myself and need some clarification.
> >
> > What's the relationship between "vtp pruning" and "switchport trunk
> allowed"?
> >
> > In one of the workbook labs, one of the tasks states:
> > 1. although it does not have it locally assigned ensure that SW1
receives
> traffic for vlan 8 over Fast0/13
> > 2. traffic for vlan 8 should not be received over any of the other
trunk
> links.
> >
> > (The two switches are trunked together on Fast0/13-15 using dot1q.)
> >
> > So my thinking is to do "switchport trunk allowed vlan 8" on
fast0/13 and
> to not allow it on 14 & 15.
> >
> > But the solution says the answer is "switchport trunk pruning vlan
> 2-7,9-1001".
> >
> > How does this solution solve either of the two tasks?
> >
> > Please advise,
> > -tim
> >
> >
This archive was generated by hypermail 2.1.4 : Fri Sep 01 2006 - 15:41:57 ART