Filtering OSPF Routes Part 2

Previously in part 1 we discussed route-filtering using the “filter-list” command in OSPF. That was limited to our ABR and ASBRs. With distribute-lists we are able to filter OSPF routes from making to the routing information base/routing table (RIB). If you recall our topology from part 1, well I’ve just added R4 to that. If …

Filtering OSPF Routes Part 1

Filtering routes is a little more complicated when we are talking about OSPF. In EIGRP it was simple. Since EIGRP is an advanced distance vector routing protocol, each router doesn’t have a perfect picture of the routing domain, it just has an idea of what’s behind our neighbor. OSPF is of course different. Each OSPF area …

EIGRP Questions to Prepare you for the CCNP!

In my CCNP notes I usually have some questions about each topic to help me solidify the material (along with labs). Here are some EIGRP questions I would recommend trying to answer. If I were you, I would memorize these questions/answers. I promise they will help! Questions: What is the administrative distance of internal EIGRP? …

Basic EIGRP Manual Summarization and Null0

EIGRP Summarization is used to simplify our routing table and advertise a summary instead of a bunch of prefixes that look the same.     My current network topology is simple, I’ve basically configured EIGRP, then used the “network 0.0.0.0” command to advertise everything and form neighbors. Here is what my routing table looks like …

Basic Prevention of Rouge DHCP Servers with DHCP Snooping

    What problem are we trying to solve? We want to prevent the rouge DHCP Server from assinging addresses out to our clients. Normally this would be your favorite wanna-be IT employee that brings his own Linksys router in the mix to fix the network 🙂 Of course it can also protect from malicious …