OSPF Timers

OSPF Timers OSPF Hello timer To discover neighbors and establish adjacency, OSPF routers exchange Hello packets at regular intervals called Hello timers. These Hello packets are sent to Multicast address group Hello replies are unicast. The Hello packet timer has ... Read More »

OSPF Network Types

OSPF network types There are three types of networks that are known to OSPF: point to point broadcast non broadcast multiaccess NBMA For each one of these network types, OSPF has an operational mode. The default operational modes are not ... Read More »


OSPF LSA Type 1: Router LSA flooded within the area generated by each router the Link State ID = the router ID of the sending router provides information about directly connected networks OSPF LSA Type 2: Network LSA flooded within ... Read More »

The Obstacle Is The Way


This audiobook is something I wished I had read it in my younger years. If you’ve heard of Aratus, Aristo, Plato, Epictetus, Marcus Aurelius… then you have probably heard of the Stoicism discipline. What I liked in “The Obstacle is ... Read More »

Cisco IP SLA Track For PBR

We learn in this blog post how to leverage Cisco IOS IP SLA tracking with PBR. Cisco IP SLA track for PBR: a sample topology I used Eve-NG to generate this network topology. Using PBR to change the path of the ... Read More »

Cisco IOU Unsupported Features

Here is a list of Cisco IOU unsupported features that you probably won’t find, when labbing using Eve-NG or GNS3. The missing features were found with i86bi-linux-l2-adventerprise-15.1b.bin image. But the same observations could be true for other versions too. Cisco IOU ... Read More »

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