Every time I teach NX-OS the same question often arises, “How good do we need to be at routing in order to pass the lab exam?” My first inkling is always to say ‘learn it all,’ but we all know that isn’t always possible. There is a ton of information to learn within the scope of this lab exam, so in order to fully understand this question, we need to look towards Cisco’s almighty guide, the blueprint!
They have gone pretty easy on us in terms of routing, but in their defense, they do have an entire lab dedicated to routing and switching. If we scan down the blueprint to Section 1.2, we see the category we are looking for:
While that comprises that entire section, I would also err on the side of caution and include Section 1.4a grouped within the L3 category, those being first-hop routing protocols such as HSRP, GLBP, and VRRP.
Look at what they ask us for here, and lets analyze it. They ask for BASIC EIGRP and OSPF, Bi-directional forwarding detection, and equal-cost multi-pathing. ECMP isn’t really its own ‘protocol’, rather something that most L3 protocols support. We will see that EIGRP and OSPF both support a default of 8 equal-cost multi-paths by default! Bi-directional forwarding detection, while a protocol, is not a routing protocol. So that leaves us with EIGRP, OSPF, and FabricPath. FabricPath is kind of its own deal within this blueprint, so I think we can safely exclude it from the remainder of this conversation too. So lets talk EIGRP and OSPF, the only dynamic routing protocols identified on the blueprint. A lot of people say…” is that all NX-OS supports?” The answer is a resounding no! NX-OS supports RIPv2, EIGRP, OSPF, BGP, IS-IS, and LISP, that’s just IPv4! We however are only going to be tested on the two protocols.
So usually the next question I get is surrounding the depth at which we must know these two dynamic routing protocols. The blueprint clearly states ‘basic.’ But what defines basic? To a route/switch CCIE, basic might mean something more advanced than say somebody coming from a strong voice or server background. This question is a little harder to answer, as they don’t give any clear indication as to what defines basic on the blueprint.
So while we could speculate all we want, I have tried to categorize things for my students as you see below. This is by no means a definitive guide, simply a professional opinion on what I would consider basic vs. advanced for these two routing protocols.
Basic
- Basic Protocol Information – know what IP ports and multicast addresses EIGRP and OSPF utilize, and know the requirements of the protocols in order to form adjacencies and exchange routing information
- Base configuration – get the protocol up, forming adjacencies, setting router-id’s, and exchanging/advertising routes
- Authentication – know the various authentication methods, and how to apply them for both protocols
- Basic redistribution – know how to redistribute direct routes, static routes, and other routing protocols
- OSPF Interface Types – know how to differentiate between P2P and broadcast network types, and how to change them
- Basic summary-addressing for OSPF and EIGRP
- Passive-interface theory and application
- BFD application
Advanced
- EIGRP Stub routing
- OSPF stub/total stub/NSSA routing
- Advanced route filtering including leak-maps, filter-lists, etc…
- OSPF virtual-links
- SPF Optimization
- EIGRP Split horizon manipulation
- Routing protocol timer manipulation
- Administrative distance manipulation
While there is much more to both of these protocols than just these bullet points, I think the above breakout does a pretty good job at defining some of the implied knowledge that the blueprint steers any CCIE DC candidate towards. When I began my preparations, these were the guidelines that I worked within (even coming from an RS CCIE background!), and now I pass them on to you!
Also, as any good candidates, we should know how to reach the configuration guide for the topics! I have learned through my exam experiences, that they will always catch you off-guard with something completely random, so knowing how to reach the configuration guide for a specific topic is crucial! As always, start with ‘root’:
http://www.cisco.com/cisco/web/psa/default.html?mode=prod
Switches->Data Center Switches -> Nexus 7000 Series Switches -> Nexus 7000 Series Switches -> Configuration Guides -> Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 6.x
This should get you to a place where you could find the answer to anything you are looking for in terms of L3 routing protocols within NX-OS! If all else fails, remember to hit ctrl-f and just search the page for specific keywords.
I should also mention that one of the hardest things for a lot of people is bridging the configuration gap from IOS to NX-OS in terms of configuring these L3 protocols. If you want some more insight on that approach, please hit up a boot camp with me in the near future or watch some of our VoD’s within our CCIE DC library!
Lastly, and I promise I will end with this! These are the only two dynamic routing protocols you will need to know for the CCIE Data Center Lab exam. However, once you pass this exam and are labeled a CCIE DC EXPERT, you will be expected to know much more, including these ‘advanced’ topics and even the protocols excluded from this blueprint. So once, you achieve those glorious numbers (or designation if you’re a prior CCIE), please don’t stop learning. Go out there and continue your education in order to fill in those few gaps!
Happy learning everyone!
