Wireless AP dropping on heavy load

[Lo¨k]

Hello all,

When there is more than 400KB/s being downloaded from the internet by a wireless client the DIR-825 says "2.4GHz Band: Wireless restart" and all the wireless clients get disconnected. I have also tried the Linksys WRT110
and the Dlink WBR-2310, they also drop on heavy load.

My question is, is it a problem with my setup or a problem with the wireless AP? If so, is there a good wireless AP that can handle in the 800KB/s of down traffic? (I'm ready to pay in the 250$+ if need be).

More details: I can reproduce a crash with only one wireless client, however most of the time there are 3 clients (max 4). Downloading a big file 1.1gig from a wireless client to another (Vista Sp1 -> WinXP pro sp2) was going at 1.1MB/s without causing the problem (the transfer was internal).

Here is my setup

cable modem -> smoothwall (old IBM box 2.66ghz w/ 756mb of RAM) -> Dlink DIR-825's gigabit switch -> 2 computers + VoIP adapter (dlink VTA)

I run the DIR-825 in AP mode (no dhcp, no QoS, no nothing) and the box running smoothwall handles everything (DHCP, QoS, Port forwarding). The problem occurs with both firmware 1.00 and 1.01.

The Wireless AP operates in the 2.4ghz band only (for testing purpose at this point) with WPA-Personal TKIP, the Group Key Update Interval is set to 3600 seconds.

I have try setting the MTU of all wireless NIC to 1300 and it did not fix the problem.

I really don't know what to do/how to troubleshoot this problem. I don't think it's interference since internal transfer works well, the strengh of the wireless network is good everywhere... I can only think of wireless AP failure but I tried 3 and they all had similar problems.

Thanks for reading.

 

[jdabbs]

You are the second person this week to complain about a restarting radio issue with the 825. Given such a small sample size, it's difficult to identify a culprit this early.

Contact D-Link tech support if you haven't already. If they've identified your issue as a problem, you may get a fix before its public release.

If I were troubleshooting, I'd also try lowering the transmit power in case the radio itself is a source of interference.

 

[thiggins]

Couple of suggestions for just shotgunning the problem:

- Turn off WMM
- Turn off WISH
- Try running with no encryption

 

[farkit55]

I have the same problem but it can definately occure while the network is idle. WMM, WISH, and QoS are all turned off.

it seems to happen most commonly right after i get his message in the log

2.4GHz Band mssid: Wireless system with MAC address mymacaddress disconnected for reason: Received Deauthentication

but the system that gets the above message seems to change. It's usually a laptop or shows a MAC of 000000000000 but sometimes it's one of the other systems.

It can also decide to reboot when there is no deauthentication event logged though.

This sucks because I really like the feature set of the 825 and the price but I've tried 2 and I can't get one to stabilize. Dlink phone support still wants to run me through their list of uselessness and is a total waste of time and I didn't even get a response from dlinks support web form.

 

[thiggins]

Sounds like it could be a bad production batch. I ran the 825 and a DWA160b1 for four hours, full blast up and downlink simultaneously without a problem.

Any chance it is heat related? Is the 825 stacked on something or in a hot location?

 

[farkit55]

It's currently sitting on a speaker which is usually turned off in a room with an ambient temperature of about 65F so if it is a heat issue it's an internal one. I picked up both my 825's from amazon i'm wondering if Lo¨k did too.

The entire 825 doesn't reboot. The OS on the device just reboots the wireless radios. It will maintain connection to any LAN devices and the the WAN network.

 

[thiggins]

I agree that it doesn't sound like an environmental heat issue. I'll see if my D-Link contacts have seen anything like this.

 

[Lo¨k]

First of all, thanks for all your answers .

I tried without WISH and WMM but it did not change much. I called dlink support and the guy told me to change the Beacon Period to 80, the RTS Threshold and Fragmentation Threshold to 2100. That didn't change much either.

I've tried to change the position of the dir-825 in my house, it seems that it's dropping less by being on the first floor... however I will have to test it on heavy load.
My guess is that there is interference with what is in the floor/roof of the house (which I have no clue what).

It seems like I see a 'restarting 2.4ghz band' when there is too much interference (my channel number is on auto) perhaps, it's trying another channel in hope of getting a less crowded channel?

I will test with channel not on auto but if I remember correctly with the 1.0 firmware, the dir-825 would stop responding if not on auto channel :|. Wonder if it works with 1.01.

thiggins: Do you think you could launch a connections test like you did for the WRT54G V5/GL? (http://www.smallnetbuilder.com/content/view/26843/51/1/4/)

 

[thiggins]

thiggins: Do you think you could launch a connections test like you did for the WRT54G V5/GL? (http://www.smallnetbuilder.com/content/view/26843/51/1/4/)

Already done and data is in the Router Charts. Maxed out at our test limit of 200 connections. (This is for wired connections.)

Do a site survey to check for surrounding networks.
How To Fix Your Wireless Network - Part 2: Site Surveying

 

[Lo¨k]

No other networks around me. I have set my ap to channel 2 which seems to work well as to now, I had 2 wireless clients and 500KB/s down with the microwave on. Connections didn't drop and the noise in Network Stubler stayed steady in the 55dBm.