Cisco 5508 Software upgrade from 8.0 to 8.5.171 - Suggestion for RTU License, WLAN Poller and AP Corruption

[CiscoWiFiGuy]

Hello Team,

One of our Client is having Cisco 5508 WLC's in HA with 8.0.152 release on controller with 3602i access points and they need to upgrade on 8.5.171 release.

I have 2 questions and appreciate if you can please share your suggestions.

While going through release notes of 8.5 , and section " Key Features not supported in Cisco WISM2 and Cisco 5508 "  Saying new release does not support RTU License / Cisco Smart License .

https://www.cisco.com/c/en/us/td/docs/wireless/controller/release/notes/crn85mr7.html#wlc-5508-wism2

Client is having base-ap count permanent license currently on controller so it that something Different in terms of RTU License . Need your help to understand this part.

Secondly release notes are saying i can go directly from 8.0 to 8.5 and same time they are also saying to have intermediate image and then upgrade to 8.5 , so please let me know which one is the ideal approach to follow.

Also just to confirm , when moving to 8.5.171 , we will not be getting effected with AP flash corruption issue as mentioned in Field Notice :

https://www.cisco.com/c/en/us/support/docs/field-notices/703/fn70330.html

To Avoid any hassel , would you recommend to run WLAN Poller prior to upgrade:

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/213317-understanding-various-ap-ios-flash-corru.html

i am trying to rule out any " Ohh nooo" scenario so i will really appreciate if you can help me while planning for this upgrade properly.

Your as Always Support is Highly Appreciated!

Cheers,

Thanks,

Waqas

[patoberli · Accepted solution]

RTU licensing needs no installed licenses on the WLC. You simply select how many APs you have and accept the agreement. No need to install any licenses. So this should not affect you.

I suggest running AP Poller with those APs before. You can directly upgrade to 8.5.171.0, just be patient, the upgrade will take a while.

I would preload the AP image before rebooting the WLC.

[CiscoWiFiGuy]

Thanks for your reply.

So lets say , for a moment if i am not running WLAN Poller and i upgrade WLC and do a pre-download image on access points , if pre-download is successful in all access point then my wild guess is that i don't have to run WLAN Poller as its main idea is to see if ap has enough memory to write the new image ?

please correct me if i am wrong as i have not used WLAN Poller earlier so i need  your suggestion on above point.

Thanks,

[Leo Laohoo]

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@CiscoWiFiGuy wrote:

To Avoid any hassel , would you recommend to run WLAN Poller prior to upgrade:

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No need.  This is only for 2700/3700.

WARNING:  The Release Notes referenced is for the 3504 which is totally a different "generation" of WLC compared to the 5508.

In the Release Notes for the 5508, it is stated that:  

If you are using Release 8.2.15x or earlier, we recommend that you upgrade to Release 8.2.16x or 8.3.x and then upgrade to Release 8.5.176.0.

[patoberli]

Thanks for pointing that out. Wasn't aware that Cisco has different release notes for those two generations.
In that case, @CiscoWiFiGuy<>, first upgrade to 8.2.166.0. Wait until all are upgraded and then start it to 8.5.176.0.
@Leo Laohoo the field notice does also list the x600 AP generation though as affected (probably because of https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvf16302
These are the only Cisco IOS AP models affected: 1600, 1700, 2600, 2700, 3600, and 3700 Series APs.

[Leo Laohoo]

The FW corruption only affected my 3700.  3500/2600/3600 were never affected. 

[CiscoWiFiGuy]

Thanks @Leo Laohoo , so in this case i will skip running wlan poller part prior to wlan upgrade activity.

Will update everyone after the activity. Hope Things will go fine.

Thanks for all your help.

[Rich R]

We definitely also saw flash corruption on 1700, can't remember whether we saw it on 1600's, but it's an IOS *software* bug (IOS corrupts the flash file system) and they're all running the same IOS so in theory it can affect all those models.

[CiscoWiFiGuy]

Thanks @patoberli  , currently 8.2.16x is in 5508 software download store but i think due to deferral notices , i am unable to download 8.2.16x software , so i am planning with below upgrade path and steps.

1) From 8.0 .152 to 8.3.150 and pre-download 8.3 image in access points and go for reboot ( WLC+AP)

2) From 8.3.150 to 8.5.171 and pre-download 8.5 image in ap and go for reboot ( WLC +AP)

[patoberli]

Sounds good. Please plan in enough time for the upgrade.
One more thing, depending on the age of your 5508, you might also want to check if you need to update the FUS for increased reliability:
https://www.cisco.com/c/en/us/td/docs/wireless/controller/release/notes/fus_rn_OL-31390-01.html
https://community.cisco.com/t5/wireless/verify-fus-1-9-to-upgrade-wlc-5508-to-8-2-151-0/td-p/3026076

[CiscoWiFiGuy]

Thanks @patoberli @Rich R @Leo Laohoo  , We managed to upgrade the WLC . It was 24/7 Production Environment so we had a downtime window of only 25 Mins . So we changed the plan ; rather than upgrading intermediate software , we upgraded the WLC directly to 8.5.171 from 8.0 ( We informed the client about the possible risk of doing that ) and then pre-downloaded the image in Access Points and performed a reboot on wlc/access point . They had some 120 access points and we were able to be back-online in around 20 mins .

Thanks for everyone's suggestions as based on your suggestions , we were ready with our tools and plan but with a limited downtime , we had to move to plan B of direct upgrade.

Appreciate your help in this regard.

Cheers.