BGP overview

Fri, 08 Dec 2017 17:52:10 +0000

Would like to put some facts about most famous routing protocol.

BGP - Border Gateway Protocol

According to Wikipedia currently we are using the version (BGP4), which was published as RFC 4271 in 2006.

BGP4 has been in use on the Internet since 1994.

Basically the world was changed by the 3 napkin protocol, the story and the picture are on Network Collective Podcast.

Its simplified finite state machine can be found on Wikipedia.

VRRP Concepts

Fri, 03 Nov 2017 16:19:21 +0000

Some quick facts :

Protocol - 112; Multicast address 224.0.0.18; Preemption Enabled(by default);Priority=100 + highest IP; Timers 1/3.6;Only master sends hellos;

**During the re-election all members will send multicast packets with same virtual source MAC - switch may see port flapping in that moment. **
Can’t advertise less than a 1 second timer - because of 1 byte field which can be 0 or 1, timers needs to be set on each router locally if you want to have a lower than 1 sec.
You better set the timers equally otherwise you might have two master scenario

What problem does it solves ? :