Problems using old internet routers as APs

RobK · 28 Apr 2017 at 17:23

The wifi signal in my house is pretty terrible, but I have wired network sockets in most of the rooms so I have been using old BT and Sky routers as access points. They all have fixed IP addresses and their built-in DHCP is disabled.

The problem I'm getting is that often my phone will connect to one of them but say there is no internet access. It appears that the phone isn't getting an IP address from my Sky Q hub, which is the router that's actually connected to the internet. If I reboot the AP it usually then works. Anyone have any idea what might be going on?

Orcvader · 28 Apr 2017 at 17:31

Make sure the "slave" routers are conncted to the main router via their LAN port, not the WAN port. On the DHCP server on the main router, shrink the range so it doesn't include the IPs of all the slave routers as well.

What models are all the routers you're using? A network map would be handy as well.

RobK · 28 Apr 2017 at 17:52

Thanks for the reply. They're all using the LAN port and their IP addresses are outside of the DHCP range. The routers are a BT HomeHub 5, a Sky Hub SR102 and a Netgear R6250. I don't have a network diagram handy but they are all connected to a Netgear 24 port switch which is then connected to the Sky Q hub.

RobK · 29 Apr 2017 at 13:11

I had a quick stab at a network diagram:

Orcvader · 29 Apr 2017 at 16:36

Any idea which router the phone is connected to when it says no internet access?

On the Netgear, have you also set the gateway to the main Sky router's IP and set the DNS to something like Google's DNS?

RobK · 29 Apr 2017 at 17:55

Orcvader said:
Any idea which router the phone is connected to when it says no internet access?

I've had the problem with both the Sky and the BT boxes. It seems to be getting more frequent for some reason.

On the Netgear, have you also set the gateway to the main Sky router's IP and set the DNS to something like Google's DNS?

The gateway and the DNS are set to the IP address of the Sky Q router, which is how the DHCP clients get configured.

This is what I see on my phone when it's not working:

joeyjojo · 29 Apr 2017 at 17:57

Also a good idea to check that the access points know the Sky hub IP is the Gateway & DNS server. I often forget to do this on DD-WRT APs and get similar symptoms.

RobK · 29 Apr 2017 at 18:00

joeyjojo said:
Also a good idea to check that the access points know the Sky hub IP is the Gateway & DNS server. I often forget to do this on DD-WRT APs and get similar symptoms.

Unfortunately these only allow you to set their IP address and netmask, there's nowhere to set the other settings

bremen1874 · 29 Apr 2017 at 18:16

If you're connected LAn-to-LAN You shouldn't need to be configuring any gateway or DNS settings on the routers you're using as APs.

RobK · 1 May 2017 at 16:23

I've just ordered a Netgear WAC104 access point to replace the old Sky hub. I'm hoping if the coverage is good I'll be able to get rid of the BT box as well.

neil_g · 1 May 2017 at 18:09

not all routers allow DHCP passthrough.

had that on a couple of older routers I was trying to use as AP.

Steve_bullockuk · 2 May 2017 at 11:36

neil_g said:
not all routers allow DHCP passthrough.

had that on a couple of older routers I was trying to use as AP.

This. Some routers have to specify a DHCP forwarding address aswell.

RobK · 17 May 2017 at 11:16

The strange thing is that they worked ok when rebooted but then at some point stopped working. The new Netgear AP is working fine so I've just got the BT hub to replace now.