Sunday, March 29, 2009

Game Plan for tomorrow

Here is how I plan to attack the lab.

1. Contrary to popular strategy, I am NOT going to do a read-through the first time. In the past I've found doing a read-through to be a waste of time because my short-term memory just ain't that good.

2. If there are troubleshooting tasks, review the config and spend 30 minutes or so trying to spot them.

3. Attack L2, IGP, and EGP immediately after. I'll go ahead and configure authentication/encryption type tasks that aren't required for core connectivity, but I won't hesitate to skip them if I hit a snag.

4. Diagram entire BGP/VPN topology. Note that I wait until core is complete before doing this. I like having a good feel for the core before starting the diagram.

5. Complete the VPN configuration. While I'm comfortable with TE now, I'll consider skipping it if it's just a few points because it just seems to have a habit of breaking other things. If I can have VPN completed before lunch, I'll be extremely happy because that should give me plenty of time to polish off the other tasks and do verifications.

6. Diagram and complete multicast. Nothing too fancy of the diagram, I just find it greatly helps me spot rpf and inter-AS issues when I have a separate mcast diagram drawn out. Unfortunately, I know how nasty multicast can be from the R&S lab, so I need prepared to give up these points altogether if need be.

7. Complete the rest of the lab. Consider skipping any traffic filtering related security tasks altogether. If I'm feeling confident in my points, I'm not even going to bother with them because I'm just too afraid of breaking my core. Seems like there's always a routing protocol or tunnel involved that get broken. If I must filter, I'm going to throw an explicit deny log at the end of the access-list so I can see everything that's getting dropped.

At this point, hopefully I have at least an hour left to go back through the lab, step by step, to verify everything. When I passed R&S, I found at least 6 points doing this that were due to stupid omissions (e.g. only applying QoS policy to R5 instead of R5 and R6).

Then, with 30 minutes left, I won't make any more configuration changes unless ABSOLUTELY necessary.

My speed has been fine though, so I'll be a little surprised if I don't have the whole lab wrapped up with 2 hours to spare. If I do, I'll probably keep doing verifications and annoy the proctor with the pickiest little questions I can think of until the labs over or the proctor kicks me out.

And here's what worries me:
Layer 2:
PPPoE. I've done a few basic configs, but it seems like it could get pretty complicated.
l2tp/AToM. There really isn't much to it, so it shouldn't give me any problems.
ATM: I have the basics down, but if some knobs get thrown my way I could have issues.

IGP: IS-IS knobs make me a little nervous.

EGP: I could have spent more time on advanced BGP features like orf and fast external failover. But these seem to be covered well in the doccd.

MPLS: ldp knobs, such as funky neighbor attributes, label filtering, and label retention

VPN: Making sure to spot if/where I need to use domain-id, sham links, and soo. Broken LSPs can be nasty to figure out too.

I'm happy with MDTs and bgp ipv4 multicast now. I'm still a little uncomfortable with MSDP. I think I just have to keep in mind that if I don't have a pim path between two hosts, I'll need two RPs and will need to join them with MSDP.

QoS: They always seem to find something nasty I haven't thought of. I'll just need to spend a little extra time verifying that what I put on is working properly

Security: Bottom line, don't break the core

System Management and IP Services: Gotta find those knobs.


Vignesh said...

Hi Ed,

All the best for your exams. Dont worry. Keep cool.

Did you go thru atleast once IPV6. I am not sure if that is covered but want to make you ensure not to leave any topic as you have spent your all efforts in preparing.

Go thru once stephen Bowes blog, how to pass CCIE SP by Himawan blogs as they got some good points to be considered during lab exam.

Kindly let me know if you need anything.

Take care and All the best


Barry said...

Hey Ed,

Best of luck to you today!