Archive for the ‘Bridging & Switching’ Category

How to re-enable an Errdisable port?

So you have configured port-security on one of your ports and we all know that by default if the violation occurs, the port will be put in shutdown-errdisable mode. One way to get the port back up is to do a manual shut-noshut on it. In today's world, this might become an administrative nightmare. What...

September 25th, 2008 | Bridging & Switching, Security | Read More

PVST+ Explained

Petr over at Internetwork Expert has been writing some great articles related to CCIE field. His Private VLANs post was a great source of information for me and I just saw his latest post on PVST+. I have not worked with spanning tree in great detail and have read a few cisco docs on it but Petr's explaination...

July 17th, 2008 | Bridging & Switching | Read More

Private VLANs explained

I was browsing through the different CCIE blogs and saw this great posting @ IE's blog. I think many CCIE students have hard time understanding Private VLANs and Petr did a great job explaining them. "What Private VLANs (PVANs) do, is they split the domain into multiple isolated broadcast subdomains....

July 15th, 2008 | Bridging & Switching | Read More

Switching & Bridging finished!

I know I have not blogged since I came back from Narbik's bootcamp. I have been thinking about how I "should have" always studied but there is no point of looking at the past. I have made up a great schedule now and will try my best to follow it. I am scheduled to go back to Pasadena on August 11th 2008...

July 3rd, 2008 | Bridging & Switching | Read More

Narbik’s Bootcamp – Day 1

Finally, the day I have been waiting for has arrived. Its 830am and I am sitting here in the class room. Comfort Inn had a nice Breakfast so I am ready to roll. We have 8 people in the class with different levels of experience. One of the guys has attempted the R&S lab 4 times already. Another guy...

June 23rd, 2008 | Bootcamp, Bridging & Switching, Frame Relay | Read More

Narbik’s Soup-to-Nuts Workbook Switching Lab 4

Lab 4 wraps up the Switching section of the Narbik's Soup-to-Nuts workbook. I was expecting this to be a little more than 6 tasks but I think this lab was designed to get you going on Private VLANs. Trust me private vlan is a great topic and majority of the network engineers don't feel comfortable with...

June 5th, 2008 | Bridging & Switching, Narbik WB | Read More

Private VLANs

Ok I have spent about 2 hours working with private vlans on 3560s. Just wanted to clear one thing for everyone reading this. Private VLANs are NOT supported on the 3550s. I didn't realize that first up but after searching in the configuration guide, I finally realized that duh - Its not supported. That's...

June 5th, 2008 | Bridging & Switching | Read More

VLAN Management Policy Server

When the VMPS receives a VQP request from a client switch, it searches its database for a MAC-address-to-VLAN mapping. The server response is based on this mapping and whether or not the server is in secure mode. Secure mode determines whether the server shuts down the port when a VLAN is not allowed...

June 3rd, 2008 | Bridging & Switching | Read More

Configuring Extended-Range VLANs on a Catalyst Switch

When the switch is in VTP transparent mode (VTP disabled), you can create extended-range VLANs (in the range 1006 to 4094 for any switch port commands that allow VLAN IDs). Enter the vlan vlan-id global configuration command to access config-vlan mode and to configure extended-range VLANs. The VLAN database...

June 3rd, 2008 | Bridging & Switching | Read More

Optimizing System Resources on a Catalyst Switch via SDM

By using Switch Database Management (SDM) templates, you can configure memory resources in the switch to optimize support for specific features, depending on how the switch is used in your network. You can select one of four templates to specify how system resources are allocated. You can then approximate...

June 3rd, 2008 | Bridging & Switching | Read More