Packet loss wireless users 802.1x

[JlassiAhmed0345]

I have two WLC 5520 on HA SOO  with flex connect APs 702i, and I have configured SSID corporate flexconnect local switching with 802.1x authentication using ISE server 2.3 as AAA server. so when we tested the network, we have faced a problem of loss packets incorporate SSID, for example when the endpoint  (phone or desktop ) launch ping -t 8.8.8.8, we remarked some loss of packets.

I isolated the problem by testing to ping -t 8.8.8.8 from a wired connection, and found that there is no packet loss which is mean that the problem is in the wireless connection.

any idea about this problem plz ? and how can I resolve it 

[balaji.bandi]

how about Wireless Gateway? do you see packet loss

how about you Router Gateway before you go out to the internet, do you see packet loss.

From the controller do you see the same packet loss?

do you have any network diagram to understand better, what all the components involved in the path from Wireless client to Internet?

[JlassiAhmed0345]

Hi sir, 

there is no packet loss from the internet router, I tested another client that used a wired connection in the same VLAN id of the wireless users and I never faced the issue of the packet loss, otherwise, when I balance to the wireless SSID using the 802.1x authentication I remark some packet loss in the CLI prompt.

below you will find the topology deployed.

[JlassiAhmed0345]

Hi is there any workarround to solve this issue ?

[balaji.bandi]

it might have slipped in our reply, Looking at the diagram

can you post examples of the same ping from SW-ACC and Wireless clients, is this a wireless client issue for all the users?

what is the end device ?

[JlassiAhmed0345]

this issue has appeared in all wireless client (laptops, android phones, ISO phones ), that use 802.1x SSID, the loss of a packet are not periodically, but it happens randomly with one or two packets of loss .

[patoberli]

How is the signal quality (noise) of the tested AP?

This could be cause by to much noise and interference in the air. 

[JlassiAhmed0345]

when I run a debug client, I found that RSSI of the connected client is -67dbm which is means is very good. i face this issue with all wireless devices, (android phones,IOS, laptops ) that are authenticated the network using the SSID 802.1x.

[patoberli]

Can you run a 'show client detail macaddress' and output here the full results?

The RSSI is only one of the important values, the SNR is a bit more important for example. 

[JlassiAhmed0345]

Hi , please you find the output of command "show client mac " here .

[patoberli]

Thanks.

      Number of Packets Received................. 5630
      Number of Packets Sent..................... 9785
.......
      Number of Data Retries..................... 3729

This looks fairly bad. Not sure why the Data Retries are so high, as all other numbers look ok. Was this client moving before you took the details?

Which firmware version is currently active on the 5520?

      Radio Signal Strength Indicator............ -75 dBm
      Signal to Noise Ratio...................... 24 dB

Here the client had a weak RSSI, the SNR was ok though (not much noise).  

If this is mostly a data wireless, you can disable some Data Rates: 

Supported Rates.................................. 6.0,9.0,12.0,18.0,24.0,36.0,
    ............................................. 48.0,54.0

If your AP density is enough, it's advised to change it on 5 GHz to the following:

6, 9 and 12 Disabled

18, 24 Mandatory

36, 48, 54 Supported

This will limit the range a little bit, but vastly increase the throughput if you use more than 1 SSID. 

[JlassiAhmed0345]

thanks for your prompt reply,

actually, my wireless controller version is 8.3.150.

[JlassiAhmed0345]

this is a screenshot of the command ping -t 8.8.8.8 from a wireless user.

[patoberli]

Can you run the Ping longer, is it (nearly) always the 10th Ping that doesn't go through? That could be background scanning of the wireless driver or Windows. 

It could also be "Off channel Scanning Defer" in the SSID settings (leave that on default values). It could also be a few other features, but before I check those, check if it's every 10 seconds (every 10th Ping). 

[balaji.bandi]

Can you post same ping from Switch that is connected AP ?

One ping results from switch

One using SVI as source where the WLAN uses