Home network multiple wireless AP issue

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fieryneck

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I had a fibre line installed in my home in January. After that I decided to enhance my network to extend my wifi coverage and get a cabled connection to my xbox. Being a software developer (i.e. professional Googler) I managed to figure it out.

2 switches, 2 wireless APs and some sweaty ceiling cable running my network was up and running. I configured the 2 identical wireless APs in the same way (same SSID and passwords) so that devices could switch seamlessly.

https://71ce63da719e30f70a35eeb5301a40f8ee0f993f.googledrive.com/host/0B115cuaBtB75WXZRM3RVRWxrbGc/NetworkDiagram.jpg

The only problem is that intermittently everything would go down. I could no longer access the Internet and could not even ping 10.0.0.2 (the 2nd Telkom router and DHCP server). When running a continuous ping some messages would occasionally get through, but most were dropped.

I would reset the router (physically since I could not access the router from my pc) and everything would run happily again for a while. This would happen continuously and was starting to drive me crazy.

Eventually, I realised that it would always happen soon after my wife went to the other side of the house to tend to our baby. While using her phone which would switch to the other AP. This seemed to be the cause of the failure.

So I unplugged Network Cable 1 and the network was reliable. When going to bed I would switch over from Network Cable 2 to Network Cable 1 so that we would have working wifi in the bedrooms. Running like this for a month I never experienced the drop in connectivity, but now I am having to deal with a lot of complaining from the wife as she has no connectivity when she is tending to the baby and I am in the living room ;)

Does anyone have any ideas what could be causing this issue? Any tips or advice of how I can get both sides of the house up and running simultaneously?

Thanks in advance!
 
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Make and model of devices?
Are the 2 waps on different channels?
Have you tried setting 2nd wap with different SSID?
 
Sounds to me like the switches aren't handling the transition between aps smoothly. So the Mac of your device is learned on one port, and when you roam to the other ap your Mac is on a different port and your device is unreachable until the Mac entry times out
 
Sinbad said:
Sounds to me like the switches aren't handling the transition between aps smoothly. So the Mac of your device is learned on one port, and when you roam to the other ap your Mac is on a different port and your device is unreachable until the Mac entry times out
Click to expand...

could also be that there isn't any transition happening at all and the phone is sticking to AP #1, as it can still hear it, but the AP cant hear the phone (stronger tx on the AP than the phone)

I think having some pings timing out, and some going through is pointing to an rf issue
 
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Wow, thanks for the quick responses.
Makes and models:
Telkom Router 1 (Fibre line in) – HUAWEI EchoLife HG8245H
Telkom Router 2 (DHCP) – HUAWEI Home Gateway HG532f
Switches – TP-LINK TL-SF1005D
Wireless APs – D-Link DAP-1360

I have not changed the WAP channels but they are quite far apart, thus the need for 2. I have tried using a different SSID on one of the WAPs but same problem.

The baby monitor was causing issues when using the installed Telkom Router 2 as a WAP (which I have now disabled), this is one of the reasons I wanted 2 WAPs on each end of the house. From within the living room the baby monitor now has little effect on the wifi quality.

I’m not sure it is a switching issue or an RF issue. When it happens, the network just completely stops working, meaning I can plug my laptop directly into Telkom Router 2, disable my laptops wifi, and still only get intermittent returns on my pings until I reset the router.

The trigger for the problem definitely seems to be when there is traffic on both sides of the house at the same time.

Could it be a router malfunction? At this stage I’m just considering buying another small switch and running my 2 cables from that with a single cable into the Telkom router, would this work?

I will try do some more debugging tomorrow night.

Thanks for your help everyone, this does seem to be a strange one...
 
So you get timeouts on the wired connection too?

IP conflict?
 
Only one dhcp server enabled, right?
 
Sinbad said:
Sounds to me like the switches aren't handling the transition between aps smoothly. So the Mac of your device is learned on one port, and when you roam to the other ap your Mac is on a different port and your device is unreachable until the Mac entry times out
Click to expand...

Brilliant - would not have thought of that!
 
@nivek Yes. Once the network starts failing I get timeouts even when connected directly to the router using a network cable

@sinbad I think there is only 1 DHCP. When I do an ipconfig /all I only see 1 DHCP Server (10.0.0.2), is there another way to check?

From my understanding, the only other network device that is capable of being the DHCP server is Telkom Router 1. I do not fully understand the need for this router. It links to the fibre line and has a network cable that runs to Telkom Router 2 and MUST be plugged into port 4 otherwise it will not work. I assume this router is 10.0.0.1 but I cannot ping it nor browse to it. These 2 routers were setup by Telkom and the only thing I have done is disable the wifi on Telkom Router 2. The 2 WAPs are pure WAPs and not routers configured as WAPs so they cannot be a DHCP.

Would a device moving from WAP 1 to WAP 2 be assigned a new IP Address, possibly leading to an IP Address conflict? I'm not 100% sure how DHCP assigns IPs but I would assume it would get the same IP since it was the same MAC address.

2 things I still need to test:
> When it fails, if I unplug one of the network cables will it restore (i.e. without a reset of the router). To date, reset is the only way I have been able to restore the connectivity again.
> If I have only 1 network cable plugged in, but enable the wifi on Telkom Router 2, does the network still fail when I have devices using Router 2 wifi as well as WAP 2 wifi.
 
Did some diagnostics this evening. Plugged in the 2nd network cable into the router and waited for the connection to get dodgy.

Once it started failing I ran some ping tests to 3 addresses: google, the router and my office mail server - 10 second timeout.

These were the results when linked to the WAP in the living room:

PingResultsWAP1.png


(the first result happened before my laptop connected to the wifi). Many of the pings are timing out. The results from the WAP in the bedroom was the same.

Then I turned off my wifi and plugged it into the router.

PingResultsPluggedIn.png


Exact same thing. I then noticed the lights for port 1 and 2 (which lead to the 2 WAPs) were flashing like crazy. I unplugged the 1 while running the same ping test:

PingResultsUnpluggingNWCable.png


This immediately fixed the problem.

Some more info, but I am still no closer to solving the issue :wtf:

Sorry, I'm not allowed to post attachments so images are links :(
 
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When you are on AP1, the Telkom router learns this, and your mac address is forwarded to Switch 1. When you move to AP2, the Telkom router will continue to send your mac address to Switch 1 even though you are connected to Switch 2. 10 seconds later, it starts to work due to what is known as a ARP timeout.

Your transparent switching, is not as transparent as you think :P

You are effectively confusing your network when moving between the devices. I would bet that your IP doesn't change and remains in fact the same (which is the root cause of the issue).
 
Thanks @savage. I think I understand.

So even though I am not moving WAPs, since my wife is moving and her device switches APs it causes this confusion and stalls the whole network? The strange thing is that moving around does seem to work, it is only when one of us is on 1 side of the house and the other on the other side both using the network that the issue seems to occur.

10 seconds or any amount of time does not fix the problem. She can even return to the living room and it still won't work. The only fix is a reset or, as I discovered last night, unplug one of the cables and plug it back in again.

Is there any way I can fix this? I will check tonight if my IP changes when switching WAPs.
 
1. Static DHCP to MAC your Device(s) on the router that provides DHCP, ensure other router does not have DHCP
2. Check which channel in your area is less populated, set AP's to that channel (not automatic)
 
I have programmed static IPs for the mobile devices on the network and it has been working well for 2 days now! So it must have been an IP address switching issue.

Thanks for all of the help everyone!
 
The problem is the access points. D-Link is crap! I had an access point that was rated at 150mbps and would drop the connection to 1mbps. I have since dumped the D-Link AP's, as they're only made to work in the room its in and instead have moved over to what I think is the best brand in Networking Solutions called Ubiquiti.

Their AP's are insane, and the price is not too bad either. If more than one Ubiquiti AP is installed, they seamlessly work together to provide your device with the strongest signal from each one. For example, if you're on a whatsapp call or Skype, but move around the house, which ever AP provides the strongest signal, the your device will automatically connect to without dropping the signal.

Visit a website called www.scoop.co.za and see what they offer.
 
fieryneck said:
I have programmed static IPs for the mobile devices on the network and it has been working well for 2 days now! So it must have been an IP address switching issue.

Thanks for all of the help everyone!
Click to expand...

Glad to be of assistance ;-)
 
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