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New Member

VTP Pruning, Management Address?

Hi again,

 

I'm looking at pruning some of our VLAN traffic across the network. We have a large number of VLANs in our VTP domain and it just makes sense to prune them out. I have a couple of questions that I'm struggling to find answers for.

1) VTP Pruning - as I understand it the VTP pruning will stop requesting any packets for VLANs not needed on the switch. How does it discern which ones to prune, from what I can see it will prune any eligible VLANs that do not have a switchport assigned to them. Unfortunately we have a separate management VLAN and every switch has an address on this VLAN, but obviously no switch ports. Will this prune the management VLAN?

2) VLAN allowed statements - on the VTP servers the trunk ports to our access level switches already have VLAN allowed statements, they are just allowing too many VLANs that aren't in use to get through. I'm assuming because the VLAN allowed statements are explicitly entered by config that they will override VLAN pruning. Will I need to remove the VLAN allowed statements to let the pruning do its job?

Thanks for your help.

Liam

  • LAN Switching and Routing
Everyone's tags (1)
3 REPLIES

Hello1) VTP Pruning - as I

Hello

1) VTP Pruning - as I understand it the VTP pruning will stop requesting any packets for VLANs not needed on the switch. How does it discern which ones to prune, from what I can see it will prune any eligible VLANs that do not have a switchport assigned to them. Unfortunately we have a separate management VLAN and every switch has an address on this VLAN, but obviously no switch ports. Will this prune the management VLAN -If  you are manually prunning your trunks then YES you will need to allow this vlan across also - and you are correct that inactive access ports assigned a vlan will be prunned ( if vtp prunning is enabled)

 

2) VLAN allowed statements - on the VTP servers the trunk ports to our access level switches already have VLAN allowed statements, they are just allowing too many VLANs that aren't in use to get through. I'm assuming because the VLAN allowed statements are explicitly entered by config that they will override VLAN pruning. Will I need to remove the VLAN allowed statements to let the pruning do its job? - YES if you manually  prune then you need to allow all vlans you required and if you have to many vlans being allowed manually and prunning is aplicable to those vlans then vtp prunning will occur as if you hadnt manually prunned at all.( if vtp prunning is enabled)

Note: once vtp prunning is enabled its propergated throughout the vtp domain

 

 

hope this helps

res

Paul

 

Please don't forget to rate any posts that have been helpful. Thanks.
New Member

Hi Paul, Thanks for your help

Hi Paul,

 

Thanks for your help. The management VLAN is 254. Should I just migrate this to an ineligible VLAN number and then implement pruning?

 

Cheers,

Liam

HelloI would personally NOT

Hello

I would personally NOT enable vtp prunning I have found it to flaky and not as controllable as manually pruning.

No need to migrate your management vlan just allow it over the trunks.

 

res

Paul

 

Please don't forget to rate any posts that have been helpful. Thanks.
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