Wireless network knocking out another wireless network

techfiend

We have 2 waps on their own networks that are spaced about 10 feet apart. Only one network is dual band. Whenever there's a significant transfer on either 2.4 ghz network the other network is unusable and often drops clients. The 5ghz network still works fine. One is set on channel 1, other on 11, but tried 6 with no effect. Would separating the wap's further improve this situation or is there something else I should be looking for?

I do the same thing at home, with 2 network waps about 20 feet apart, and they don't knock each other out.

NOC-Ninja

what kind of APs?
what kind of WLC?
what kind of TS have you guys done?
why is it 10 feet apart?
have you done a site survey swipe to check any interference?
is there any other business close to your business location? they might have AP's too.

techfiend

Ubiquiti wap plugged into switch and dual band tp-link router/ap plugged into router, no wlc. 10 feet apart because that's about as far apart they could get in the server closet without hunting for an extension cord. Full signal on both wlan's throughput the office. For 90% of the office there's no other wlan's. 10% there's a wlan from a neighboring company that bounces between 1 bar and unreachable. TS?

Codeman6669

So even if they are on different channels when devices such as AP's are in the 2.4 band and they are placed to close to another device in the same band they can interfere with each other. First thing i would do, would to find a centralized location between your AP's and see if you even need two of them, or if one will give you proper coverage. 10 feet is quite close, i kinda of doubt you need two, but im not there.

If that is not possible, then you will need to lower the transmit power of the AP's.(lowering each one) It should be in the settings of the AP itself.
Also first do a channel scan in the AP. This will scan the 2.4 band for neighboring SSID broadcasts (such as your other access point). It should show dbm in a - value. In the scan you will see your other AP, and you want to adjust the transmit power down to get the two Ap's seeing each other at about -70. Anything -60's or lower can cause interference. (the lower the number the higher the signal strength) Alternatively moving the AP's further apart from each other would create the same effect. It is best to use one AP at full transmit power then it is to use two at lowered transmit power. Because reduced output means reduced speeds in more areas. (isnt wireless fun?)

But i would see if you just need one AP first.
let me know how it goes

Additionally to verify it is the problem between the two waps. Turn one off and test. If it seems improved then now you know what to do.

techfiend

Thanks for the power suggestions. We use 2 because the ubiquiti is on the network, tp-link off the network, we require both situations but maybe I'll look into 1 with a guest network, can this be trusted though? The switches are unmanaged so tough to setup a vlan for the mobile.

Codeman6669

guest network can be trusted. typically they are put on a different subnet and have a setting to make it so those devices on the guest etwork can only get to the internet, not other devices on the network.

techfiend

Thanks, I'll work on it again next week.

Edificer

Well, I had a funny incident today, we got a call today from one of the departments saying their internet did not work so the help desk guys told them to restart the routers and it would work, to infinite entertainment they reset it back to factory default settings unintentionally! We had a good laugh out of that. Not their fault.

We were dealing with 2 tp link routers and we put one in channel 11 and the other in 1, and we disabled DHCP on the one where the wan port is unplugged. It's working.

techfiend

I spent some time on this again. DNS served through DHCP became an issue. DHCP is required to give out ip's on the guest network with external dns servers, however the internal clients occasionally grab from the internal wifi and they require internal dns servers. I eventually returned it to how it was.

Now thinking I could set internal dns servers first then external. That would cause a slight delay on the guest network connections but should allow everything to work. Is this a way to get it working effectively?

It would be nice if DHCP only broadcasted to the guest network but I'm pretty sure it's not possible with the TP-LINK router.