March 9, 2009 by ted.

Last week I converted our new distribution to VSS. If you haven’t heard anything about Cisco VSS yet, you should check it out. VSS is used on the 6500 chassis if you have the new VS-S720-10G-3C supervisor. The concept of VSS is pretty easy to understand. If you are familiar with stacking 3750 switches, you will understand VSS. Basically, you take two 6500s and make them look like only a single switch to anything that connects to them.

Some reasons to use VSS are to get rid of spanning-tree between the distribution and access layers. You also no longer need to use HSRP. For example, an access switch connecting to your distribution would usually be dual-homed, meaning connecting to two separate distribution switches. With spanning-tree, in most cases, one of the uplinks will be unused for a given vlan. That means if you use 10 Gig uplinks, one is unused and only for redundancy (you can balance vlans to even things out, but that has to be configured). With VSS your access switch would have only one port channel that would actually connect to both distribution switches. From the perspective of the access switch, it’s only connecting to a single switch (even though it’s physically two separate switches). Since we only have one port-channel to the distribution, HSRP or VRRP is not needed. One vlan IP is assigned to the VSS distribution switch, and clients use that as default gw. Load balancing across links is done using the traditional etherchannel hashing algorithm.

Check out http://cisco.com/go/vss

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March 2, 2009 by ted.

Continuing my recent trend of reviewing some of the new CCNA material, my friends over at Pearson were kind enough to let me review the new online flash cards for the CCNA Security exam.

Summary

The first thing I want to point out is that this material is online only, so don’t expect to receive a printed copy. Unlike the CCNx flash cards of the past, this is online based which is the best way to go. The flash cards cover the exam blueprint objectives of the CCNA Security 640-553 exam.

Exam blueprint link

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February 21, 2009 by ted.

Hello

Charles

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February 20, 2009 by ted.

I decided to upgrade our two Nexus boxes to the latest code before putting them on the network. The procedure is a bit different compared to a regular IOS upgrade. You need to download two files– the NX-OS image, and the “kickstart” image that corresponds to it. I chose to connect to the management port on the supervisor to upload the image. It’s in its own vrf so don’t forget that when trying to ping, etc.

Here is the process below as I did it ::

switch(config)# inter mgmt 0
switch(config-if)# ip address 1.1.1.2 255.0.0.0
switch(config-if)# no shut
switch(config-if)# end

switch# ping 1.1.1.1 vrf management

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February 18, 2009 by ted.

Pearson was kind enough to send me a copy of ExamCram CCNA Voice 640-460 to review. I have to honestly say that this was my first time ever reading an ExamCram book so I was very curious to see what they are all about.

First off, I’m extremely glad to see some expansion in the associate Cisco certifications. I think this will make it a lot easier to get more exposure to the Voice, Security and Wireless tracks. Seeing that they now have voice offerings is a great thing for both employers and their employees. Man, I look forward to being able to teach CCNA again!

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