Caffeinated thoughts about wi-fi and our world

What NetWare Taught Me About AirCheck Upgrades

I have learned a few tricks over the years to make my life a little easier by way of managing change. My pastor used to refer to the wisdom of "older players" who had learned to avoid making life unnecessarily difficult for themselves. One professional example of this (learned the hard way on a couple of occasions) is to be careful about when and how I apply firmware or software updates to critical systems and tools. I cut my teeth professionally as a server admin for a couple of big energy companies years ago, and learned all about change management in a very demanding environment. To this day, no matter how excited I am to try newly released code, experience has taught me to wait until I'm finished with the current project, report, or deadline before pressing the launch button. But good maintenance habits go beyond scheduled outage windows, and at times a relatively trivial procedure can remind us that best practices are best practiced with minimal exception.

What Happened

By the end of the week I was more than ready to check out the new features in the AirCheck G2 firmware version released a few days prior. I decided to wait until my usual Friday night window for personal device maintenance. This upgrade was a nice reminder why that patience is a good idea, and why even more patience almost always pays for itself.

To upgrade a NETSCOUT AirCheck G2, you connect the unit to a Windows computer running AirCheck G2 Manager software via the supplied USB cable, which in addition to facilitating device updates, allows you to download saved session files, backup device profiles, and offload screenshots. When I connected the AirCheck and clicked the Help button on the lower left, I browsed to the Device Info > Firmware Update section just to double-check the process. It's straightforward enough: Browse to http://www.netscout-f.com/downloads for the latest firmware download file and click the Update AirCheck G2 Firmware button in the Manager software's Device Info tab. Follow the instructions and don't do anything stupid like interrupt the process. Got it.

 Latest Aircheck G2 downloads

Latest Aircheck G2 downloads

When I browsed to the download site, I also picked up a new copy of AirCheck G2 Manager (version 1.1.372), the release notes, and a copy of the latest Vendor MAC Prefix file. Insert ominous foreshadowing sound effect here.

 Ummm... Something's up. There's ALWAYS a lot of Fi in my house!

Ummm... Something's up. There's ALWAYS a lot of Fi in my house!

The firmware update process seemed to go as planned with no indication of any problems. The instructions tell you to wait for the AirCheck to reboot, wait for it to update, let it reboot again, let it update a little more, and then wait for it to return to a connected status with the Manager software. After that you should be able to disconnect the AirCheck and move along your merry way. After my unit re-established its connection to Manager, I went ahead and transferred the new Vendor MAC Prefix file, which is nothing more than a plain text mapping of MACs to manufacturer organizationally unique identifiers. It never hurts to be up to date. When I disconnected from my laptop, however, something was immediately amiss.  The AirCheck didn't appear to be scanning, and the AutoTest and Ethernet Test buttons were grayed out.

Firmware updates being what they are, I reminded myself I had an entire weekend to roll back or find a fix. I referred to the release notes, which suggested that if those very two buttons were grayed out after an upgrade, a simple reboot would restore order to the AirCheck's world. Unfortunately, a couple of attempts later I found myself still scratching my head and wondering what my best, next options were. I re-downloaded the firmware file, reconnected the AirCheck, and tried again. Rinse and repeat; no luck. The Manager software showed the new firmware version applied, but my device seemed, for lack of a better term, hung or frozen. It was then I remembered that I'd violated one of my own principles of systems management: Whenever updating critical components, do one thing a time if at all possible. Nothing warned me against applying the new Vendor MAC Prefix file before disconnecting my unit after the firmware update, but "older players" should know better. 

“...the same principles apply as when I was doing Saturday morning patches and DSRepairs on Novell file servers at Conoco 15 years ago.”

Digging though my downloads, I also noticed that my Prefix file had been automatically renamed by my file system due to a duplicate file name. In the abundance of caution that inevitably prevails in the wake of a sideways upgrade, I saved the previous copies to another directory, re-downloaded the file (just in case), re-connected the AirCheck, and applied the update. A few seconds later everything was back to normal, and I could check out the cool new features in version 1.1.

The 802dotKey

The real point of this post isn't about the firmware and Vendor MAC Prefix file updates of NETSCOUT's AirCheck G2. I can't even say for certain whether I uncovered the true root cause--it may have just been a fluke (no pun intended). I only included all that detail in case it does help others if they find themselves in a similar situation. My true motivation was a quick reminder to myself and others to practice good system management and maintenance habits at all times. This may have been just an update for a personally owned wireless analysis tool, but the same principles apply as when I was doing Saturday morning patches and DSRepairs on Novell file servers at Conoco 15 years ago. Be deliberate. Be precise. Give yourself recovery options. And don't make things more complicated than they need to be. Not only does this reduce the likelihood of encountering problems along the way, it significantly simplifies the troubleshooting process when something unexpected does take place. All these years later I still occasionally need that reminder, but I'm thankful this time it was gentle and confined to the scope of my own anxiety. One of these days maybe I'll carry the more permanent wisdom of an older player.