Applying "route-map" in interfaces with encapsulation dot1q

[zsmr00001]

Hello,

I would like to ask you if there were some trouble  in applying route-maps in a interface and its subinterfaces, as it is shown:

interface GigabitEthernet0/2

 ip address 11.0.9.26 255.255.255.252

 ip policy route-map GestionRadios
!

interface GigabitEthernet0/2.11

 encapsulation dot1Q 11

 ip address 11.0.9.18 255.255.255.252

 ip policy route-map RedOperativaA

!

interface GigabitEthernet0/2.12

 encapsulation dot1Q 12

 ip address 11.0.9.22 255.255.255.252

 ip policy route-map RedOperativaB

I am not sure if it is correct totally. Besides I get this informacion doing "show ip  policy" and it seems to be right.

Router#show ip policy
Interface      Route map

Gi0/2          GestionRadios
Gi0/2.11       RedOperativaA
Gi0/2.12       RedOperativaB

I would be very grateful for your help.

Thanks in advance

Regards,

Sandro

[Richard Burts]

Sandro

We do not have much to work with in your post so giving you really good answers is difficult. You do not tell us what type of device this is (I assume probably a router, but perhaps it is a layer 3 switch?) or what version of code it is running. These things make a difference sometimes in what is supported or is not supported. But since you get output in show ip policy then I assume that the device does support configuration of this feature.

You show us the configuration of the interfaces but not the configuration of the route maps or the access lists which the route maps probably use. So we can not form an opinion of the validity of the route maps or the access lists.

And you do not tell us whether the Policy Based Routing is working or not (and in fact you do not tell us for sure that you are doing PBR - though that is generally what route maps on the interfaces are doing) so we are not clear whether there is a problem here or not.

But based on what you show us in this post I do not see any particular problems with the route maps and the way that you have applied them to interfaces (assuming that your goal is really to do PBR).

HTH

Rick

[milan.kulik]

Hi,

actually, I'd say configuring an interface and its subinterfaces, as it is shown:

interface GigabitEthernet0/2

ip address 11.0.9.26 255.255.255.252

ip policy route-map GestionRadios
!

interface GigabitEthernet0/2.11

encapsulation dot1Q 11

ip address 11.0.9.18 255.255.255.252

ip policy route-map RedOperativaA

!

is a little obsolete syntax used in old times when encapsulation ... native option was not available yet.

So I'd recommend to change to:

interface GigabitEthernet0/2.x

 encapsulation dot1Q x native

ip address 11.0.9.26 255.255.255.252

ip policy route-map GestionRadios
!

Then you will have all your subinterfaces configured the same way.

Best regards,

Milan
 

[zsmr00001]

Hello,

Ok, thanks. I asked you this because I read before that the policy in interface override or overwrite the polices in subinterfaces, is that true?

This device is Router 2911.

Best regards,

Sandro
 

[milan.kulik · Accepted solution]

Hi,

maybe it was related to QoS policy (not PBR) which was supposed to be inherited on the subinterfaces when applied on the main interface?

In both cases I think it's safer to use subinterfaces only.

Best regards,

Milan

[zsmr00001]

Hello,

Ok, Thanks. I wanted to ask you this, because someone said to me that the policy on interface overwrite the polices on subinterfaces, also I read that sometime. This router (2911) is already configured and we see that only a service has a weird behaviour, and before doing changes I wanted to ask your about this.

Best regards,

Sandro

[Richard Burts · Accepted solution]

Sandro

It may be for some features like QOS that policy applied on the physical interface is passed down to the subinterfaces. But that is not the case with route maps applied for Policy Based Routing. If you apply it on the physical interface then it affects only the physical interface and not any of the subinterfaces.

HTH

Rick