IP redundancy

I have queries regarding the redundancy issue (cisco).

Scenario: End Customer has Primary-backup set up. I have checked the configuration and found no redundancy protocol is used in it. (sh vrrp , sh glbp, sh standy have no results) .

My Query

Could the router have redundancy even if the above protocol is not used? (Is it thru the access list? route-map configuration ??)

How to check if both routers are redundant?

if Back to back access is unavailable, Could someone help with the configuration? (no physical cable is connected between both the device to get access to primary via backup or vice versa)

Hello Aparna

The term “redundancy” can refer to many features that deliver network resiliency. It could refer to a first hop redundancy protocol (FHRP) such as VRRP, GLBP, or HSRP, but it can also refer to routing protocol redundancy, where OSPF or EIGRP are configured with load balancing or alternative routing. You can also have layer 2 redundancy with multiple layer 2 links using STP, or with EtherChannel set up with multiple physical links. Or you may be referring to features such as VSS or StackWise or vPC for Nexus switches.

Can you specify what kind of redundancy you are referring to so we can help you further?

I hope this has been helpful!