Wireless clients sporadically getting Limited Connectivity, APs dropping packets

[John_Rowler]

We have a pair of V2110 wireless controllers and around 400 3825i access points. Controller firmware is 09.21.06.0002. AP firmware is 9.21.27.1387X.

About 4 months ago we noticed a problem where the APs would just drop traffic. A packet capture will show a ping coming into the radio from the client, going out the Eth interface on the AP, the reply coming back into the Eth interface, and never going out of the radio.

A particularly strange detail is that this only happens with certain source/destination traffic. For instance a client cant ping the gateway of 10.1.20.1/24. but cannot pint the server at 10.1.20.2. Since we can see the ping making it to the server and the ping reply making it back to the AP, we know it's not a firewall/ACL/routing issue on any other part of the network. The traffic disappears at the AP. Clients cannot communicate with anything on the Internet or any of our servers (DNS, DHCP, etc.) during this time. They can ping gateways in any subnet but that's it; everything else is failed.

More details:

-We've gone through several firmware updates with GTAC. Nothing has helped.
-The issue can affect any client on any AP in any location at any time.
-The issue is intermittent; it may happen every few minutes or once per month to a particular client in a particular area. Once failed it may last for seconds or days.
-While it's affecting one client, other clients on the AP may be working fine or may also fail.
-It can happen on either 2.4 or 5.7GHz.
-It can affect any type of client (phone, laptop, tablet) and any OS.
-Restarting the client or AP will sometimes fix the issue, sometimes not.
-It happens with our without using NAC, or any other type of authentication. It happens on completely open networks as well.
-It happens on both bridged at AP and bridged at controller topologies.
-It's not limited to a particular subnet or VLAN.
-It happens with or without Flexible Client Access enabled.
-It happens on either controller.
-GTAC hasn't made much progress on the issue in 4 months.

[FES]

Hi,
Im confused... Extreme said us that we must use 10.11.xx instead 10.01. But the last improves and corrected bugs are solved in 10.01 releases... I have to believe that 10.11 release don't have this bugs...
Since two days we have a better behavior in our infrastructure... no aps moving through the controllers, no disconnected clients... ALL PERFECT.
The change that we have made is to reserve all the memory in the resources tab of the vm. (i find in GTACK https://gtacknowledge.extremenetworks.com/articles/Solution/v2110-wireless-controller-may-run-out-of...)
If you have problems with your V2110 you can try this...
Byeeee

[Alexandr_P]

Hello, Andre!

Why do you think that 10.01.06.0006 was released after 10.11.x.x?

I look at - https://extranet.extremenetworks.com/downloads/Pages/WirelessControllers.aspx:
Release dates
10.01.06.0006 - Monday, July 11, 2016
10.11.03.0004 - Tuesday, September 20, 2016

Thank you!

[Andre_Brits_Kan]

Hi

From my open case the following improved alot of the problems:

Disable MFP (not all clients support/like this.)
Enable uapsd
Enable short guard
Set DTIM 1
pmode auto
AMPDU enable
ADDBA enable
Enable station event logs

Also install the version 10.01.06.0006 not the latest version 10.11.x.x.
Version 10.01.06.0006 was released after 10.11.x.x and it addresses alot of the 38xx series problems:

• Optimized background scanning algorithm to improve stability of AP3800 series APs

• Corrected issue that could cause inadvertent blocking of Client’s ARP traffic

• Addressed possible instability for AP3800 series devices in handling of client connectivity management feature (Steering, Balance, Probe Suppression) wns0015218 Relaxed timestamp validation for Fast Failover user registrations to allow for time drift from the AP

• Adjusted validation logic for derived key maximum key length for 802.11r (Fast Transition) configuration. Misconfiguration could cause AP3800 series radio to not initialize correctly.

• Addressed issue with limited connectivity for Intel Clients. See known issues for other cases

[Sai_Prasad_Rao_]

As per Extreme recommended OS version is 9.21.10.0005 for dis connectivity issues

with below settings:
enable Probe Suppression
enable Force Disassociate
RSS Threshold -80 dBm
Change Radio 2 (2.4Ghz) settings from 802.11 b/g/n to g/n

[FES]

At now we have stable configuration, with correct roaming behaviour, with Probe Supression Disabled... we have all avanced configurations disabled and we have no desconexions... in 9.21.008 version. We have deleted the sesion_timeout value at radius config because we had macbook desconexions.

We need to upgrade soon to v10 because we have 39xx aps. Anyone have problems with this version? Any recomended version?