Android phones zero upload on guest SSID

[JWC929]

I have a strange issue with certain clients on our Guest SSID.  We have centralized 5520 WLC and 9800-CL controllers.  9800's are VM's used only for anchoring Guest traffic.  We have 2 separate data centers and have sites split between them geographically.  Users homed to data center 1 don't seem to have issues.  Some users that are homed to data center 2 have issues with zero upload speed.  Microsoft and other business apps do not function.  Web browsing still seems to work.

We have been able to reproduce this issue and it only seems to affect Android users in data center 2.  Apple users do not report the usability issues and post normal upload and download speeds when doing a speed test.  I moved access points from a site that was homed in data center 2 over to data center 1 and the issue was no longer observed on the Android devices.  I moved them back to data center 2 and the problem began again.    All controllers have the same code versions.  All the data center hardware is the same or very similar.  Any ideas where to look here?

[Flavio Miranda]

Hi

    It seems the problem is related to the path between the site to the DC2 as per the test you did. Do you have any security system on this path?  Like IPS. Any, the who handles the guest portal?  Is it the WLC or ISE?  If ISE, is the same ISE for both DC ?

[JWC929]

Both DC's have the same firewalls and same policy.  ISE is not being used for this network, our guest SSID is open.

[Rich R]

Even if they're all on the same software versions, are they all up to date?
Refer to TAC recommended versions below.