Write Erase - Remove VLANS

Another common question I see from people setting up a Cisco lab for their CCNA is...

"I did a write erase on the switch but the old vlans are still there. What gives?"

Well, doing a write erase will remove delete your startup config but it doesn't touch the vlan database.

If you would like to remove all traces of previous vlans as well as startup configurations do the following.

Rack1SW4#del vlan.dat
Delete filename [vlan.dat]?
Delete flash:vlan.dat? [confirm]
Rack1SW4#write erase

Make sure you answer no if prompted to save your config.

This works on Cisco 2900's, 3550's and 3560's and possibly others but I haven't tested them.

Cisco Lab Console Port Config

I have gotten a few emails about what console port configuration I use in my lab. These questions were from people studying for the CCNA and I thought it might be helpful information for a post.

The below config prevents the console port from timing out. It also stops those annoying "*Oct 8 08:54:27.180: %SYS-5-CONFIG_I: Configured from console by console" messages when configuring a device.


R1>enable
R1#config t
Enter configuration commands, one per line. End with CNTL/Z.
R1(config)#line con 0
R1(config-line)#no exec-timeout
R1(config-line)#logging synchronous
R1(config-line)#exit
R1(config)#exit
R1#


*Note "exec-timeout 0 0" is the same as "no exec-timeout"

Cisco service configuration boot error

Are you getting one of these errors on a Cisco Device?

%Error opening tftp://255.255.255.255/network-confg (Socket error)
%Error opening tftp://255.255.255.255/cisconet.cfg (Socket error)
%Error opening tftp://255.255.255.255/3620-confg (Socket error)
%Error opening tftp://255.255.255.255/3620.cfg (Socket error)

Well, here is how you fix it.

Router#config terminal

Router(config)#no service config

Router(config)#exit

Router#copy running-config startup-config

And you are done! You will not see that error again!

Cisco - Regular Expressions

I have used regular expressions for years when configuring Cisco routers. However, the bulk of my use of them has been when configuring BGP. However now that I am using them for dial-peers in our Cisco routers used for our VOIP system, I have decided that I need to commit this information to memory. Up until now every time I write an regular expression I have to refer to the documentation.

For those of you in the same position as I am I have included some links.

Cisco.com - Dial Peer Enhancements - 12.1T
Cisco.com - Regular Expressions - 12.2
Brcraju Blog - Learn how to write a Regular Expression

Firefox Add-on - Ad Blocker

I have been using the Ad Blocker add-on for Firefox for a few days now and I must say it is one of the more useful ones I use. It allows you to subscribe to a list of sites to be filtered. You can customize that list as you see fit. However, my favorite feature of this add-on is the ability to simply right-click on an "image ad" and block it. This is really handy for me since most of the sites that host their own ads that aren't listed in the filter list provided with the add-on.

https://addons.mozilla.org/en-US/firefox/addon/6826

ASA license upgrade!!!

Do you need to upgrade your ASA's license? Well here is how you do it!!

To upgrade the current license of your Cisco ASA, you need to order a new license key from Cisco or your local Cisco Partner. You will then receive your PAK (Product Authorization Key) number from Cisco. Then you will need to enter your PAK and the serial number of your ASA at www.cisco.com/go/license. Keep in mind that if you have two ASAs that you need to do each ASA separately. After that you will receive a new license key in your email after a couple of hours.

To apply this new license key in your security appliance, configure the following:

ASA5500(config)# activation-key (insert key)
ASA5500(config)#exit
ASA5500#write mem
ASA5500#reload

From Universe to Multiverse. Are You Ready? (Dr. Michio Kaku)