topic Re: File transfer issue over wireless Network in Wireless

File transfer issue over wireless Network

Farooq Muhammad — Mon, 05 Jul 2021 20:15:55 GMT

I am facing a recently explored issue . The network is recently deployed with 10G LAN Infrastructue such as Access and Core switches . The wireless is composed of Cisco 5520 Controller and the latest Catalyst 9120AXI access points.The ISP internet speed is 100Mbps.
The internet speed is perfectly fine when check with speed test on both LAN and Wireless Lan.However , the users are facing issue when uploading a file to any cloud services such as Google drive etc . The file upload takes for example a 4GB file over the LAN shows 6-7 Minutes , while the Wireless shows 60-80 Minutes.
Iperf tests results are fine when tested with an 802.11ac client and server .

The problem is the same when tested on an AP where 10 users are connected and an AP where no user is connected . Distance from laptop to AP hardly 2m.

Speed and duplex settings on switch ports to AP , UPLINK and Controller interfaces all verified.

We can understand wireless is not comparable to Wired but this seems too much unacceptable.

I can provide any output required.

Any urgent response is appreciated.

Re: File transfer issue over wireless Network

saravlak — Wed, 05 May 2021 02:38:03 GMT

check, if any uplink throttle configured in wlan or wired side for the wireless client. try from WLAN that doesn't have throttling.

There doesn't appear to be wireless issue based on wireless iperf result.

may need to check the continuous upload speed and report to ISP, if a specific issue identified.

Regarding internet speed:

https://www.speedtest.net/

what's the basic speed test result for UP & DOWN from the test AP.

Download this utility and try the continuous(upload) speed test to get an idea.

http://startrinity.com/InternetQuality/ContinuousBandwidthTester.aspx

check RF connection:

Check client connecting Radio, RSSI/SnR, connection speed and the rate it maintains.

Re: File transfer issue over wireless Network

Leo Laohoo — Wed, 05 May 2021 03:29:31 GMT

What is the model of wireless NIC?
What driver is the wireless NIC running on?

Re: File transfer issue over wireless Network

Scott Fella — Wed, 05 May 2021 04:28:38 GMT

First thing I would do is test your local LAN with iPerf. If that is fine like you stated, then wireless is not the issue and is something upstream.

Re: File transfer issue over wireless Network

Farooq Muhammad — Wed, 05 May 2021 09:01:37 GMT

The Wireless NIC details are attached.

There is no issue with ISP since the file transfers with Wired network has no issue at all.

No throttling configured at any point.

Re: File transfer issue over wireless Network

Leo Laohoo — Wed, 05 May 2021 10:33:55 GMT

Before we begin any troubleshooting, upgrade the driver of the wireless NIC card.

Download link can be found HERE.

Re: File transfer issue over wireless Network

Farooq Muhammad — Wed, 05 May 2021 11:39:05 GMT

Hi Leo,

Thanks for the response . The driver is now updated to 22.40.0.7 .

Now i am testing on an AP with no other client , distance is 2.5 m for the client test machine.

I have noted one observation , the download speed seems ok as 500Mb file only took 1minute to complete.The upload for the same file is showing 30 Minutes.

Which is not the case with Wired upload.

Hope we can get into some results now.

Re: File transfer issue over wireless Network

Leo Laohoo — Wed, 05 May 2021 12:26:45 GMT

Can you add a different test: Copy the same file from one computer to another (wireless client to another wireless client).
Try to avoid going to the WAN link.

Re: File transfer issue over wireless Network

Farooq Muhammad — Wed, 05 May 2021 12:36:30 GMT

Sure , i will do now this and attached is the show client output.

Re: File transfer issue over wireless Network

Farooq Muhammad — Wed, 05 May 2021 13:42:01 GMT

The same file via local transfer between the two Machines ( transferred as shared folder) in the same SSID takes much less time . 500Mb file almost 70 Sec . Transfer speed showing 5-7Mbps.

The same case for local transfer has been repeated between different SSIDs with one machine in another SSID and the reponse is identical with end result of 70 sec.

Re: File transfer issue over wireless Network

patoberli — Wed, 05 May 2021 14:02:23 GMT

Do you have special QoS or AVC enabled on the SSID?

And just to confirm, it's also slow when copying from one Wi-Fi client to one wired client without going through internet?

On the switch connecting to the WLC are you using a port-channel? Is LAG correctly enabled on both sides:

http://www.firewall.cx/cisco-technical-knowledgebase/cisco-wireless/1223-how-to-configure-wlc-lag-and-port-channel-with-nexus-catalyst-switches.html

Re: File transfer issue over wireless Network

Farooq Muhammad — Wed, 05 May 2021 14:43:20 GMT

Yes Patoberli, the LAGs are already configured with dual 10G ports . I did the LAN to WLAN transfer of the same file on the same two machines , the response is similarly acceptable as between local WLAN.

AVC is not enabled on WLC.

There is only a firewall and WAN router involved for internet . Firewall is permitting any any for testing phase and are not giving any different treatment to packets from LAN or WLAN , infact both are permitted via same rule.

Re: File transfer issue over wireless Network

saravlak — Wed, 05 May 2021 15:59:09 GMT

it appear, its one of the following ie., either at the source of AP or at the edge of your network.

Do you've a special switch port config for wired devices Vs AP switchports for the upstream.

in your network, There could be uplink throttle set on wired/DMZ-infra for all wireless users/VLANs leaving the internet.

check for any filtering/proxy services adding delay.

Re: File transfer issue over wireless Network

Rich R — Wed, 05 May 2021 17:05:57 GMT

Try "config ap tcp-adjust-mss enable all 1250" - that will only help for TCP traffic, not UDP.
Try using a browser with QUIC (HTTP/3) disabled.for the uploads (to force it to use TCP).

Are you using the latest code - 8.10.151.0?

How you checked all your switch and router ports in the path for input/output drops and/or buffer failures? (feeding 10G infra into 100M can cause microbursts resulting in drops).

Is this flex local switching or central switching over CAPWAP?

Have you done a packet capture on the device, on the AP-WLC connection (if central switching) and at the connection to your internet router (ideally synchronised) which will show fragmentation, packet loss, retransmissions etc?

Re: File transfer issue over wireless Network

saravlak — Wed, 05 May 2021 17:08:32 GMT

Good Suggestions!!!

Re: File transfer issue over wireless Network

Leo Laohoo — Wed, 05 May 2021 23:23:33 GMT

So the transfer from one wireless client to another wireless client takes only 70 seconds?

This just proven this is no longer a "wireless issue".

Can you check the router if any QoS is enabled?

Re: File transfer issue over wireless Network

Scott Fella — Thu, 06 May 2021 07:18:19 GMT

Out of curiosity, can you provide a screen shot of the iPerf test from the local lan? Also, have you tired iPerf test on some public iPerf servers? Also do the same test from a wired laptop on the same subnet as the wireless client for both local and public iPerf.

https://iperf.cc/

https://iperf.fr/iperf-servers.php

Re: File transfer issue over wireless Network

Farooq Muhammad — Thu, 06 May 2021 12:10:53 GMT

There is no QOS enabled any where on the network including WAN Router , Firewall and no proxy etc.

Checked the complete path there are no drops on the interfaces.

Re: File transfer issue over wireless Network

Rich R — Thu, 06 May 2021 13:56:01 GMT

So then you need those packet captures and try the config I suggested.

You should really be doing packet captures right at the beginning to understand problems like this.

Re: File transfer issue over wireless Network

Leo Laohoo — Fri, 07 May 2021 07:44:57 GMT

@Farooq Muhammad wrote:

There is no QOS enabled any where on the network including WAN Router

WTF ...
You have a 100 Mbps link and no QoS or traffic shaping policy is in place?
I think that is where the problem is.

The router is probably trying to push (up the WAN link) more than 100 Mbps and the ISP is dropping the packets.