Upgrading WLC IOS version

[interfacedy]

Hi Please see the section of cisco document (its link is listed below)

8.5 Mainline

The 8.5 Mainline branch supports 5508/8510/5520/8540/3504/2504/7510/WiSM2/vWLC controllers.  It supports intercontroller mobility (IRCM) between AireOS and old "New Mobility" ("Converged Access") controllers (5760/3850/3650.)  It does not support IRCM with 9800 controllers.  For 8.5 Mainline deployments, TAC recommends 8.5.171.0.

https://www.cisco.com/c/en/us/support/docs/wireless/wireless-lan-controller-software/200046-tac-recommended-aireos.html

The question is why TAC recommends 8.5.171.0 for upgrading AireOS since lateted recommended one is 8.10.162.0? 

Thank you

[marce1000]

 - But the paragraph only focuses on the 8.5.x train (only).

 M.

[interfacedy]

Thanks marce1000 for your reply. Not very sure your reply. Do you mean if we need to use 8.5, we can use 8.5.171.0 that cisco recommended? 

[marce1000]

  - Yes , 

 M.

[Arshad Safrulla]

8.5 has IRCM releases and Mainline releases. 

Mainline releases are for WLC's which doesn't require any Mobility tunnels with 9800. ICRM releases are required to build Mobility tunnels with 9800 WLC's.

[interfacedy]

Does 8.10 have IRCM releases and Mainline releases? 

[marce1000]

 - It's a bit of a wrong question , you need to look at IRCM compatibility requirements only for inter-controller roaming when controllers have different AireOs releases , in that case  requirements according to this table must be met :

            https://www.cisco.com/c/en/us/td/docs/wireless/compatibility/matrix/compatibility-matrix.html#ircm_aireos_rls

 M.