SVI and Subinterface

[4everlearning]

Can i use a subinterface (for example 10,0,0.10 for a L3 BGP connectivity. if Vlan 10 is configured on my router for another service and has SVI configured for it as well ?

is there any relation between SVI and L3 Subinterface ? or the subinterface number has nothing to do with SVI or vlan and i can choose any number?

[Jon Marshall]

Not sure I fully understand.

Do you mean allocate a subinterface in vlan 10 and give it an IP from the same IP subnet as the SVI ?

If so then no I don't think you can because the router would complain about an overlapping subnet when you tried to give it an IP address.

If you mean something else then please provide some more details.

Jon

[4everlearning]

Thanks for the reply.

No a completely different subnets will be used on the subinterface.

This is the case, There is a vlan (10) configured on the router for internal connectivities and has SVI configured for that vlan for a specific service.

Now can i still use sub interface .10 for a connectivity to external network with like MPLS (PE-CE) connectivity while using different range ?

would that be fine ? or since vlan 10 is used and also there is a bridge (SVI) associated with it, i can't use the same number for sub interfaces on the same router ?

[Jon Marshall]

The actual number of the subinterface as far as I know is largely irrelevant.

However if you had the line "encapsulation dot1q 10" under that subinterface that would tie it to vlan 10 and there I think you may face a problem.

Jon

[4everlearning]

not doing encapsulation (would it be configured by default on sub interfaces?, if so i will disable it) , the sub interface (10.0.0.10) will connect to \MPLS through ebgp. so from what i understood  from your reply is that if i will use that link for ebgp connectivity using .10 subinterface will be fine even if there is on the same router a vlan 10 configired with svi ? 

[Jon Marshall · Accepted solution]

Yes you should be able to use the same number on the subinterface number. There is nothing that will tie it to the SVI as far as I know.

Jon

[4everlearning]

Many thanks Jon.