What's the best way to follow ( in general ) choosing between which routing protocols to deploy in network ( whether internal or external ).
What I mean is:
* When it's best to use EIGRP.
* When it's best to use OSPF.
Clearly BGP is mostly the favorite in WAN links.
Please find a link below of a document written by Jeff Doyle. Hope it will explain you question.
That depends on a lot of factors, but I guess the most important is do you have now or will you use non-cisco routing capable devices in the future. If so and you want to run EIGRP, are you comfortable supporting and are your devices capable of running multiple routing protocols. If you run EIGRP, there is a possibility that you might want or have to run OSPF in the future, and if so you will at the least have two routing domains, and one router running both protocols, but there is also the possibility of a re-design to move completely to OSPF.
Now, there are a tons of other factors as well, but it really depends on the particular network and its requirements. Also, knowledge of each protocols is also a factor.
Thanks guys. Others with thoughts/preference ?
Adding to the above...just a one liner from me :), EIGRP is Cisco proprietary, so you might want to consider OSPF if you are having a multi vendor environment.
If you have an entirely Cisco environment, one super positive note for EIGRP is that is one of the fastest coverging routing protocols on the block, and no pesky areas to configure.
This seems to be the common rationale and a best practice of sorts