interface templates question

[tasost]

Hi community,

I have a question on interface templates. I created one and want to apply to a trunk port which contains the "usual commands" with vlan filtering. Can I apply the template in parallel and will there be any downtime or impact on traffic when removing the "usual commands" and leaving the source template?

e.g
interface GigabitEthernet1/0/20
 switchport trunk allowed vlan 2,3,8,11,12
 switchport mode trunk
 source template Test-Template

Thank you,
Tasos

[Mark Malone]

Hi
If you remove the usual commands the trunk will break on one end which would cause an outage and an stp re converge depending on setup ,so it may depend whats in your template to replace the usual commands ? usually these auto templates like macros and interface templates are instantaneous in terms of applying the config but i would think the interface may still flap but i don't use them so i cant confirm that part exactly

[tasost]

Thank you Mark for the quick reply.

In the template there will be the same commands:
switchport trunk allowed vlan 2,3,8,11,12
switchport mode trunk

and apply template to different interfaces

[Mark Malone]

I would think if the template is applied to the interface first and then you remove the commands it will still be up in the trunk as the template is applied , but i would test it first on a non critical interface to be sure as i said i havent tested this feature yet

You could even connect a pc to a free port , set the template with some access commands apply it then remove its manual commands and see if the interface flaps , it my give you an indication of what will happen at the interface level for the trunk , if the interface flaps it may do so for the trunk which could cause a slight stp recalculation depending on your design and size of layer 2 network

[tasost]

Thank you, I will try it and come back