I was watching INE videos about RIP and when I reached the RIP Authentication video, I apparently forgot about the key number must match requirement when using MD5. To be honest, it wasn’t the only one I forgot about RIP. Heck, I usually forget what I read last night! It’s a constant struggle […]

RIP Authentication

OSPF behavior using different interface types. Interface Type Uses DR/BDR? Default Hello Interval Requires a neighbor Command? More than Two Hosts Allowed in the Subnet? Broadcast Yes 10 No Yes Point-to-point 1 No 10 No No Nonbroadcast 2 (NBMA) Yes 30 Yes Yes Point-to-multipoint No 30 No Yes Point-to-multipoint nonbroadcast […]

OSPF Network Types

Ever seen this error message %TUN-5-RECURDOWN: Tunnel1 temporarily disabled due to recursive routing? The most common reason for this error is that the router is trying to route to the tunnel destination address using the tunnel interface itself. This error message will keep flooding your router until someone fixes the […]

GRE Tunnel Recursive Routing

When you’re building a Cisco home lab, make sure to buy switches and/or routers that will satisfy the requirements of the track you’re currently studying for. You may also want to future proof your home lab for other Cisco tracks. Future proofing was one of the reasons why I didn’t […]

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