GigaWave Technologies: Giga-News

Q:	Several of my colleagues and I have run into a few problems with our IOS to LWAPP AP upgrades. What can I do to troubleshoot if this happens to us in the future?
A:	If you have ever performed an IOS to LWAPP upgrade, you’ve probably been successful in doing so. However, there are those rare instances when the AP upgrade fails. For those that have experienced this problem, the following upgrade tips from a GigaWave instructor will offer some guidance on how to troubleshoot the issue, saving you precious time.

“I don’t know, but I’ve been told, that AP ain’t got no soul….”

Okay, maybe I’ve been listening to a little too much Zepp lately if a failed IOS to LWAPP upgrade gives me flashbacks to “Black Dog”, but you have to do something to fill the lonely voids while upgrading your APs and “getting the Led out” is my guilty pleasure. How many of you have been there already? You made your IOS to LWAPP upgrade checklist:

And now that all of your requirements are in place, you start the program down its automated course. And you wait.

And you wait.

And you wait some more. Its not that the process is slow, because it isn’t – Cisco has improved the process so you can upgrade up to 6 APs at the same time, but it still takes time. The really good news is that 99.9% of the time they will all upgrade successfully and the rest of this article is a meaningless collection of pixels.

But what about that .1%, when the AP upgrade fails. Or what if your AP is already converted to LWAPP code and the LWAPP image gets corrupted, which is also rare, but happens – what do you do then? Don’t give that lump of plastic that used to be an access point to your Uncle Henry so he can use it like a clay-pigeon until you’ve tried these tips out….

>>	Download and install Cisco’s LWAPP Upgrade Utility
>>	Schedule the maintenance period so nobody complains about downtime
>>	Make your text file
>>	Make double and triple sure that all the autonomous APs you’re about to upgrade meet Cisco’s requirements (no 802.11b radios, no RM20A modules)
>>	Configure the controller to allow telnet

Step-by-Step Instructions

If the initial upgrade from IOS to LWAPP fails, revert back to IOS.

1.	Set up a TFTP server with an IP address of 10.0.0.2-30.
2.	Download the IOS image file for that model of AP from Cisco and name the file with this format: cmodelnumber-k9w7-tar.default. For example, the image file for an 1130 access point would be c1130-k9w7-tar.default.
3.	Make sure the AP and TFTP server are on the same subnet.
4.	Disconnect the AP from power, push the mode-reset button (you may need a pen or paperclip for this), and hold while reconnecting power. Keep the mode-reset button pressed in until the status led turns red. a. Note that if performing this step on an 1130 access point, the lid will have to be pushed back which will disengage the status led. In this case, watch the Ethernet and Radio leds, as they will both turn red. b. Once the Status led has turned red, the AP assigns itself an IP address of 10.0.0.1/27 and reaches out for a TFTP server. It finds the image file named for its model of access point, downloads it (during which time the status led will turn an almost purplish shade of blue), and a few minutes later the AP will reboot and come up as a defaulted IOS-based access point.

You have now recovered the AP back to IOS, allowing you to try Cisco’s LWAPP Upgrade Utility again. If it works, great, but what if it doesn’t? If the utility fails again, and I’ve had it happen, they go on to one of these alternate methods of upgrading your AP.

Use a different version of the Cisco IOS to LWAPP Upgrade Utility.

I know it sounds too simple, but I’ve seen it work in some cases. Try it. If it fails, you can always recover the AP back to IOS and try using IOS based commands (the next method).

Use IOS-based commands to upgrade.

1.	Open your web-browser and enter the url: http://access point’s IP address. You can get this IP address by using Cisco’s IP Setup Utility (a free download) or by looking at your DHCP server for a new lease for a host named “ap”.
2.	Navigate in the menu to System Software>Software Upgrade>TFTP Upgrade and enter the IP address of your TFTP server and the name of the recovery image you’ll be using to upgrade your IOS-based access point to LWAPP. a. Note that this will be the same recovery image you were going to use with Cisco’s LWAPP Upgrade Utility, except now you will be accessing it a different way. b. If you are a command-line fiend and think the GUI is for sissies, then you could use the archive download-sw command from the CLI and achieve the same result.
3.	This will put the recovery image on the access point. The AP will now be LWAPP dependent and will need a controller to connect to.

Recovering an AP that was successfully upgraded to LWAPP and then went bad.

Every once in a while you will have an AP that was successfully upgraded to LWAPP – you know it was successful because you used it as an LWAPP-based AP, but then something happened and the AP will no longer “land” on a controller, or if it does, it stays (permanently) in a downloading state. This happened to me when I was setting up indoor mesh with an early release of mesh code for the 4402 and some 1130 access points. When I converted the AP mode on the 1130s from Local mode to Bridge mode the APs downloaded new access point code to support mesh functionality… and went into eternal download mode, trying to download code from the controller, but never coming back into a usable state. Fortunately, the solution is easy; you just use the mode-reset button.

Remember that the access point already has an LWAPP recovery image on it, so it already has code on it that will make it reach out and talk to a controller. The problem is that it downloaded another copy of code (in addition to the first) that for whatever reason has become non-responsive.

1.	Disconnect the AP from power.
2.	Press and hold the mode-reset button while reapplying power. Do this long enough for the status led to turn amber -- This should take about 2-3 seconds.
3.	Release the mode-reset button -- This will flush out the additional code and any configuration the AP has and take it down to the unconfigured recovery image. This unconfigured recovery image will then reach out, find a controller, and download code from it.

Don’t walk away from this with the wrong impression… Cisco’s IOS to LWAPP Upgrade Utility rocks and will get the job done for you 99.9% of the time or more. It lets you upgrade large numbers of access points and it will upgrade access points that require a self-signed certificate (all APs manufactured by Cisco before 17 July, 2005 fit in this category), but if the utility ever fails, you now have an alternative to singing the opening notes of Led Zeppelin’s Immigrant Song.

To learn more, contact GigaWave Technologies at 210.375.0085 or info@giga-wave.com