Static vs Dynamics Routing Protocols

My network consists of 5 25xx/26xx routers and 5 networks. Our network configuration changes very little. We use a frame relay T1 link to connect to our corporate cloud. The WAN uses OSPF for routing info. Because of that, I set up OSPF on all our routers to standardize. However, I would prefer to use mostly static routes for our network to help take a load off the routers. They aren't exactly high performance routers and each router is already load balancing multiple T1's.

At what point do static routes become a burden to manage? My only real experience with static routes is setting the default route on each router. Is there a good rule to use for deciding to use static routes vs dynamic? I don't want to switch over to static routing if its a pain to manage. However, most of our networks are stubs and I am leaning towards going static.

Any advice?

Hi

Static i always prefered over any Dynamic routing protocols because it consumes very less processing resources. Static routing hold good only over LAN/WAN with no or very very less network change..

In cases where you keep your LAN/WAN network changed often / frequently, then Dynamic holds the best. With static routing it will be a complete rework on the routing table each & every time you make some changes ( ofcourse its change dependent).

If its network changes in frequent interval I would prefer you plan to change your router keeping the routing protocol the same.

Thanks
Paul

I can't imagine OSPF for 5 networks to create any measurable consumption of resources (processing, memory or network), so if you have performance issues I don't think disabling dynamic routing is going to be of much help. Then again I'm used to thinking in the scale of pentium-class-pc performance so perhaps things are different in hardware routers and it can make a difference.

Concerning the management burden, just like Paul said, it all depends on how often you will do addressing changes in your network. If you do not mess with subnets all the time it won't be much of a pain updating the table for each one of your 5 routers every time you do (5-10 minutes work). Static routes are also prefered from a security standpoint -though it's not a very typical exploitation, under the proper conditions it could be used by an attacker to capture traffic he could not otherwise, or cause DoS.

For such a small network static routing sounds good and I'd go for it.

The only thing to add really is that if you're implementing static routes remeber to also add routes to cater for any failure scenarios. For example, you might define a second higher cost route to a destination using a lower bandwidth line in case your main line fails. The thing about static routes is that they are, well, static. So you need to allow for situations like this

Thanks for the info. That just verifies what my understanding was. I know my current setup doesn't overload my routers but I would like to keep the resources as low as possible... well... because... that's just how I work...

Thanks guys!