"What is the correct way to start OSPF routing between the stacks on Site 1? "
Normally, insure the one or more subnets that exist on the trunk are covered by an OSPF network statement. (NB: in your 1st follow up post you mention "Routing between this sites is static." but your using OSPF?)
"Will it be correct if I create new vlan on Stack 1 and 2 only for ospf connectivity, and declare all other vlans passive-interfaces?
Or is it better to make routed link between stacks (and keep existing trunk too) and run OSPF over this link? "
Either would be better for faster OSPF convergence if the connection is lost between the two Site 1 stacks. Both also avoid possible issues with multiple paths when max exceeds max supported by OSPF. Both also help preclude rogue OSPF neighbors. Of the two, I would lean toward using a dedicated VLAN on the trunk. Another option would be to use one or a couple of existing VLANs configured active and others configured passive.
BTW, ". . . implement optimal routing." also would need to consider bandwidths between L3 devices and typical traffic patterns between them.
We are pleased to announce availability of Beta software for 16.6.3.
16.6.3 will be the second rebuild on the 16.6 release train targeted
towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are
looking for early feedback from customers befor...
Introduction Featured Speakers Luis Espejel is the Telecommunications
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