IOS Upgrade

According to Guy Almes, “There are three kinds of death in this world.  There’s heart death, there’s brain death, and there’s being off the network.”

Over the past couple of weeks I’ve been forced to upgrade and downgrade the IOS for my core switch several times because of a bug in the code.

I’ve been on pins and needles the entire time since at any time a simple interface reset would cause the switch to reboot, bringing my entire network to a screetching halt.  Obviously that is not a good thing, but all I could do was wait on Cisco to come through with a new IOS that should fix the bug.

Buggy

A while back I posted about Undocumented Features.  Well Cisco recommended we upgrade the IOS on our core router to see if that would alleviate the bug. Our old IOS was version 12.2(33)SXH5.  The new one was 12.2(33)SXH7.

We did the upgrade last Thursday but it seemed to not fix anything. I still saw the”static NATs” building in the translation table.

Oh well. I figured at least we’re at a new rev. We’ll just have to troubleshoot some more to find the true problem.

Cue the next day. At lunch we were working on configuring our new wireless controller. The last bit of configuration we needed to do would bounce the port-channel interface between the controller and the core router.

We had permission to do this during lunch because it was Friday and there are always fewer people online. Besides, we were only affecting the wireless network in one building. What could go wrong?

Well the high resurfaced in a big way. When the port-channel interface bounced, it rebooted the entire core router!

Twice…

Most Useful Basic Cisco IOS Commands

Here’s MY list of what I consider the most useful commands in Cisco IOS.  Most are pretty basic, I know, but I use them all the time when troubleshooting or configuring.  They are definitely worth remembering.   

Happy Monday!

Monday’s are wonderful, aren’t they?  I mean, it’s awesome to walk in first thing in the morning and find things are already broken.  The gremlins were working overtime this weekend, I see.

I get in and I’ve not even logged into my PC yet and one of the desktop techs approaches me about a possible user port being down.  So he waits patiently at my door, chatting with other folks outside my office as I finish logging in and trying to get into the switch remotely to see what’s going on.  Unfortunately, I cannot get into the switch.  I can ping it, but telnet and web access weren’t working. 

Ugh.

Redundancy, Redundancy, Redundancy…I’ll say it again Redundancy.

The rep from my ISP just called and asked me how my Internet and WAN connections were doing.  He seemed taken aback by my answer of just fine.  Apparently, someone cut some fiber somewhere and took out our entire county.

Except us.

I had a hunch this call would be coming.  My CIO had been waiting at my office when I walked in the door this morning (a little late, too!  **gulp**).  She asked a very similar question, but I informed her that from what I could tell everything was working just fine.  I’d not received any automated outage notifications either from our ISP or from any of our internal network monitoring devices.  She’d heard from some collegues at the local community college that they were down and they wanted to know our status.  I told her I’d look at our systems and let her know, but at the moment all is working and as far as I could tell we never went down, even for a blip.