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.

[Marlon]

Hi

we having the same issue where clients suddenly disconnected (need to reconnect manually) from WLAN or clients are connected but cannot reach any network including the gateway. we are using the latest Firmware version 10.11.01.0210 Controller C35 and Access Point 3801i.

can someone share the solution.

thanks
Marlon

[Sai_Prasad_Rao_]

Hi All

Limited connectivity issue is observed if 5Ghz Channel width is set to 40mhz.

If in case if anyone is facing limited / dis-connectivity issues and if your 5Ghz Channel width is set to 40mhz change it to 20mhz.

I have faced the issue and found out solution by myself. Now Issue resolved 🙂

[Alexandr_P]

Hello, Gareth!

Wi'll test 10.01 and 10.11 and after that I will have a full understanding.

Thank you!

[Gareth_Mitchell]

Alexander

10.11.x was a feature release bringing amongst other things application visibility, http redirect at AP etc (see release notes for full list.)

10.01.06 was released after 10.11.01 as a final maintenance release in the 10.01.x track, 10.01.x is now complete and there will be no more changes in this branch of code.

10.11.03 contains all current fixes and is the firmware of choice in this 10.x line (10.11.04 is currently expected by the middle of next week.)

If you have problems that 10.11.03 hasn't resolved, please open a case with GTAC and we will get it looked at.

-Gareth