Wireless clients intermittent loss of network connectivity and failure to connect to the network

[kwanghyun]

Hello.

I'm a beginner engineer who started my network management career.

I manage wireless network services using WLC 5508 and 2702 AP.

Wireless clients continue to experience symptoms of not being able to connect to the AP's signal.

In addition, connected clients are experiencing intermittent loss of connection.

I tried to look up the data and deal with it, but it didn't work out easily, so I'd like to ask for help.

Thank you.

[Rasika Nayanajith]

What software version running on your 5508 ? "show sysinfo" output on WLC CLI will provide that info (if not WLC GUI page)

Rasika

[kwanghyun]

Hello.

The version currently running on WLC is 8.2.151.0.

AP is operating in flexconnect mode.

Thank you.

--------------------
Manufacturer's Name.............................. Cisco Systems Inc.
Product Name..................................... Cisco Controller
Product Version.................................. 8.2.151.0
Bootloader Version............................... 1.0.1
Field Recovery Image Version..................... 6.0.182.0
Firmware Version................................. FPGA 1.7, Env 1.8, USB console 2.2
Build Type....................................... DATA + WPS
System Name...................................... WLC_B
System Location..................................
System Contact...................................
System ObjectID.................................. 1.3.6.1.4.1.9.1.1069
Redundancy Mode.................................. SSO
IP Address....................................... 192.168.5.6
IPv6 Address..................................... ::
Last Reset....................................... Software reset
System Up Time................................... 133 days 19 hrs 49 mins 57 secs
System Timezone Location......................... (GMT +9:00) Tokyo, Osaka, Sapporo
System Stats Realtime Interval................... 5
System Stats Normal Interval..................... 180
Configured Country............................... KE - Korea Extended (CK)
Operating Environment............................ Commercial (0 to 40 C)
Internal Temp Alarm Limits....................... 0 to 65 C
Internal Temperature............................. +42 C
External Temperature............................. +23 C
Fan Status....................................... OK
State of 802.11b Network......................... Enabled
State of 802.11a Network......................... Enabled
Number of WLANs.................................. 125
Number of Active Clients......................... 541
Burned-in MAC Address............................ BC:16:65:F8:78:20
Power Supply 1................................... Present, OK
Power Supply 2................................... Present, OK
Maximum number of APs supported.................. 500
System Nas-Id....................................
WLC MIC Certificate Types........................ SHA1

[Rasika Nayanajith]

Thanks for sharing that info.

You are running 8.2.x version which is bit old. So it is better to go with later code (8.5.151.0 at least). Anayway check what AP models you got (I know you said 2702, is that the only model or you got mix of different models). Check   below document & make it a bookmark for future reference

https://www.cisco.com/c/en/us/td/docs/wireless/compatibility/matrix/compatibility-matrix.html#56735

Before come to a conclusion, do bit more investigating & find out what clients having this issue (phones,tablet,laptops) & what operating system they running. If issue is only to particular device type, then pay attention to wireless drivers & its firmware version. You may be able to find some co-relation.

HTH

Rasika

*** Pls rate all useful responses ***

[kwanghyun]

Thanks for your help.

The site is a 24-hour manufacturing plant. That's why upgrading versions is difficult.

The client's OS has the same symptoms as Android, Windows 10. (Symptoms do not appear only on specific clients.)
The symptoms are the same with the latest update installation of the drivers for the client.

Thank you.

[patoberli]

Could be signal coverage issue or/and software bug of the old WLC code.
Did you do a site survey before the network was installed? If not, take a mobile phone and an app and change the signal strength. It should be at least -70 dBi.