I have a few questions related to the method of L3 peering between N7k and a generic L3 device (let's say it is a router) - the idea is to connect N7k to the core network. The current design is based on Cat6k switches (they are the core of my network) which have many Vlans and SVI interfaces for them.
EIGRP is also used currently on Cat6k and other L3 devices in my network.
The goal is to extend Vlans from the current Cat6k to a pair of N7k configured for vPC. To do that I would have to configure L2 trunks (and NOT to use vPC links) between Cat6k and a pair of N7k and use them to pass all the current Vlans to N7k. How to establish EIGRP adjajency between Cat6k and N7k and at the same time pass all the vlans? Should I add any new Vlan on N7k/Cat6k, create SVI for it and use it to establish EIGRP peering?
Is the above the correct thinking? if not how to do that?
- One of the design docs say that we MUST use L3 routed interfaces to connect these two devices (N7k and a core network).
- Other ones mention that the _recommended_ way is to use L3 routed interfaces to connect these two devices ('recommended' means what? that any other options are available? what are they?)
- And other ones say that can use Vlan peering (through SVI interfaces) if only we make sure not to use vPC vlans (peering of routing protocols using a VLAN also carried on the vPC peer-link is not supported). Does it mean that if I configure any new/additional Vlan between the core and the vPC domain + I would exclude that vlan from vPC peer-link that I can configure EIGRP/OSPF peering between a generic vPC device and vPC domain???
what about STP root and HSRP? During the migration can they stay on the 6K till I move all my servers from 6k to N7k?
Will the communication be ok? or I can came across the situation that the traffic would be filtered by the peer-link of N7k?