Switch: failing at the first hurdle.

I'm on the first chapter of the switch OCG and reading about TCAM operation - my brain is now turning to jelly!!! I think this will take a few re-reads.

I obviously need to get this nailed but it's a blow not to understand something that early on. Ironically, I don't think there's anything else in the whole blueprint that I haven't done before at work! But none of it has ever involved a detailed understanding of the TCAM table. Actually, that's a lie for effect, I've never touched wireless and my. CCNA preceded the inclusion of it.

Ho hum, going for re-read number 3. Then I'll see if I can fond reference to it in the CBT nuggets; hearing it conveyed by someone else usually helps.

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Chris_

It's okay, it's clicked- I had the epiphany, it takes each access list as a whole not each line, therefore if there are 8
lines in your ACL and all your wildcard masks are, for example, 0.0.255.255, then this only generates 1 mask in the TCAM against which all value patterns generated from your ACL are compared - even better, the last paragraph of the chapter basically says don't worry about how it works, it just does - and there's nothing you can do to change it apart from making sure you use the most efficient ACLs you can!! Love it, glad I persisted though.

BrizoH

I actually prefer the opposite way - watching the CBT Nugget first to give me an overview, then reading the cert guide for the finer details.

Glad it clicked for you though, best of luck with your studies!

Chris_

BrizoH wrote: »

I actually prefer the opposite way - watching the CBT Nugget first to give me an overview, then reading the cert guide for the finer details.

Glad it clicked for you though, best of luck with your studies!

Thanks.Funnily enough, so do I usually but just felt like sitting down in a quiet room with the book, thinking that the switch operation chapter would just be review - haven't looked yet, but I doubt the TCAM operation is something that Jeremy will go into in any depth.

shednik

BrizoH wrote: »

I actually prefer the opposite way - watching the CBT Nugget first to give me an overview, then reading the cert guide for the finer details.

Glad it clicked for you though, best of luck with your studies!

I do the same!

mikka1984

With ROUTE I've done CBTs, lab the topics, then do FLG/OCG, than lab like there's no tomorrow. Don't have OCG for SWITCH though, heard it wasn't that great so got FLG.

Chris_

I got the OCG because I've covered a lot of the material before, both in the real world and in study. I've done most vlan, vtp, stp and hsrp stuff at work. I have the CCNA voice and security, so that covers most of the voice and l2 security setup. As such the OCG seems to be a good, concise, coverage of the blueprint. I know the book is missing bits on network monitoring and management but, in David hucaby's defence, he did create a blog just to add the material for these topics.
With route I found the OCG pretty awful but this one looks good

JaCkNiFe

mikka1984 wrote: »

With ROUTE I've done CBTs, lab the topics, then do FLG/OCG, than lab like there's no tomorrow. Don't have OCG for SWITCH though, heard it wasn't that great so got FLG.

I used the OCG as my primary book resource next to the CCNP SWITCH Lab Manual and I was more than adequately prepared (I downloaded the Errata and Apendix for the OCG). I did skim through the FLG for a few details here and there for a more in depth look at things but I think the OCG gets a bad wrap. /2cents

GA1

JaCkNiFe wrote: »

I used the OCG as my primary book resource next to the CCNP SWITCH Lab Manual

What is this CCNP SWITCH Lab Manual? I don't think I've heard of it.

DPG

Amazon.com: CCNP SWITCH Lab Manual (Lab Companion) (9781587133046): Cisco Networking Academy: Books

It has some rather basic labs that will help you understand almost anything you would see on the exam.