Dynamic Routing Protocols - what do I really need to know?

[rival9217]

Ok, ridiculously broad question I know but....what I'm trying to figure out is, let's say I'm in a large coproration and I have multiple field sites in different areas of the country so the network setup may be somewhat complex but when it comes to setting up the dynamic routing...is it as simple as let's say, configuring a router to use BGP for whatever portion you designate then just letting it be? is it somewhat challenging to initally configure dynamic routing protocols (i.e. how often have you found yourselves worrying about admin distance, areas (I don't even know what an "area" is yet either so if anyone could explain that I would appreciate it), etc..

So in short, are dynamic routing protocols "Set it and forget it" or do they require a ton of planning to setup? I'm familliar with the differences between them (i.e. OSPF, RIP, EIGRP,etc..) and the differences in link state and distance vector but I just wanted to ask about the setup of the protocols themselves.

Thanks!!

[rival9217]

To give futher info, I know dynamic routing gets more complex as you network grows and I know that you can't have two different protocols talk to each other. But I'm guessing the configurations don't take long, yes of course, if you had to configure multiple routers to speak to each other it may get a little time consuming but even then, most of your time would be spent just making sure you're entering the correct address and what not - I'm not seeing a need for entering a ton of commands on each router.....correct me if I'm wrong.

[Jon Marshall · Accepted solution]

You can exchange routes between protocols with redistribution.

The problem with the question is, as you say, it is too broad to really answer properly.

All routing protocols have different considerations so what you might do for EIGRP you may not do with OSPF and BGP is different altogether.

As a general answer if you are enabling it across a WAN all take a certain amout of planning and design and they all rely heavily on what you have done with your IP addressing in terms of summarisation etc.

The actual configurations to get a basic setup running are relatively simple, certainly for IGPs, but as your network grows you may find the configurations becoming more complex

BGP is a very different in that there are many different commands you can use to influence the path traffic takes but even here to setup a very basic BGP peering only requires a few commands.

But no routing protocol in a large environment should just be configured with no thought as to how it is going to work, traffic paths, number of routes etc.

You can do it but you may well find as your network grows you will end up having to revisit the whole thing because it is not working as you intended.

Like I say it's too large a question to really answer because each routing protocol is different and may or may not meet the requirements of the network.

If there are more specific questions then please feel free to ask.

Jon