CCNP SWITCH 642-813 and GNS3 – part 1 Introduction
December 14, 2010 3 Comments
If you want to become a Cisco Certified Network Professional engineer you need to prove the ability to plan, implement, verify and troubleshoot local and wide-area enterprise networks
Your ability is tested with these three Cisco exams:
The SWITCH 642-813 covers Local area network part of CCNP exam and tests candidate knowledge and skills necessary to plan, configure and verify the implementation of complex enterprise switching solutions using Cisco’s Campus Enterprise Architecture.
I would like to share my experience with GNS3 that I used for deploying network devices configuration of certain topics the CCNP SWITCH exam certification.
Now, let’s go answer couple of questions.
Do I need to use GNS3 for CCNP switch?
No, not really. If you can allow to buy couple Cisco Catalyst switches let’s go for them. Ebay prices are usually good and everybody knows that any simulator (emulator ) on the world can’t replace hands-on experience with real network devices.
Why the simulator can’t be enough for deploying Cisco switches configuration?
Because of its nature – it is artificial, command limited, bugged and not sufficient for CCNP configuration level. Think about all of bugs in real IOS and add all other bugs that comes from simulator. Sometimes you don’t know if the problem is in your configuration or you find another bug in software.
Once when I configured STP in Packet Tracer I was not able to get my configuration working – after doing some troubleshooting I was sure that problem is not related with my configuration. And really, I had to reopen Packet Tracer to get my configuration applied.
Ok, money is not a problem. What switches do you recommend?
You need two Layer 3 switches for building Distribution Layer switches and one (or two) Layer 2 switches for access layer. It should be enough.
What kind of switches do you mean?
Two Layer 3 Cisco 3560 with Enhanced IOS image should be ideal and you can use them later in your CCIE R&S lab. On the other hand you can do almost all CCNP SWTCH configuration (except Private VLAN ) with 3550 switches that are more cheaper than 3560s.
Some people buy 3550s and rental rack session for PVLAN. Everything depends on your budget. I was lucky to play two days with Private VLANs on eight port 3560 switch which I borrowed from my work.
In my home lab I used one 3550 switch loaded with EMI IOS (ipservicesk9-mz.12.2.55SE.bin).
Check these links for 3550 and 3560 comparison:
You also need one (or two) Access switches. I used two old 2950 switches with last (i6k2l2q4-mz.121-22EA13) IOS. It allows me to configure all STP types (PVRST+, RPVRST+, MST), port Access list, dot1x.
What can I do if I can’t afford any real equipment?
Nothing is lost at all. You can use Packet Tracer (available for download for Cisco Academy students) or GNS3.
Although GNS3 (Dynamips) can emulate only certain old router platforms(17xx, 26xx, 26xxXM, 2636×0, 37×5, 7026VRX and 7206VXR with NPE-G2) you can add NM-16SW module to 36xx or 37×5 or 2691 model and enjoy basic switching capability.
Router supplies routing capability and NM-16SW provide L2 switching features. In this configuration you can create VLANs, trunks, EtherChannels, SVI ports and even VTP is running. Spanning Tree Protocol is limted to PVST+ only.
If you have old 2950 switches you can connect them to your PC running GNS3 with 3725 router/switch device. In this scenario you save cost for expensive Layer 3 Cisco switch.
The link bellow shows list of missing features with the 16 port switching module (NM-16ESW) for the 3725 in comparison to the 3550 Catalyst switch.
OK, I checked the link above and NM-16SW module is very feature limited comparing to real Cisco switch. What good does GNS3 with Dynamips bring on the table?
Using router’s IOS you can use some features which are not available in real Cisco IOS Switch. For example First Hop Redundancy protocols – VRRP and GLBP are available only on Cisco Cat switches 4500, 6500 series.
You can create nice LAB in GNS3 and implement Cisco hierarchical network model with gateway redundancy protocols using Dynamips emulated router. I’ll show this configuration in next parts of this tutorial.