Posted: Thu Oct 19, 2017 8:14 Post subject: Client Bridge and AP with External Router/DHCP Server
I'm having an issue with client bridge mode. The DD-WRT client bridge router is set up to connect to a DD-WRT AP. The AP has DHCP, WAN and the firewall disabled. This AP is connected LAN-to-LAN to the Ubiquiti router. The Ubiquiti is connected to the modem, and is what's serving DHCP, doing NAT, and is the firewall.
The CBR and AP both have different local IP addresses than the Ubiquiti, but all three are on the same subnet. The CBR and AP's gateways are set to 192.168.1.1 which is the local IP address of the Ubiquiti router. The problem I am having is that in this setup, if I ping the AP or google, I get fairly severe packet loss. I can get internet traffic coming through, but there are severe delays in loading pages, obviously because of the packet loss. If I ping the CBR which I have a wired connection to from my PC, I get DUP packets coming back.
Wireless clients connecting to the AP have no issues whatsoever. I then tried WDS mode and all of the above problems mostly went away, except it's not reliable as the WDS station will eventually lose connection with the WDS AP. Rebooting the station isn't enough to get it working again, and I had to change the Wireless Network Mode on the WDS AP to something else and back again to get it to reconnect, just short of rebooting it. In WDS mode accessing the WDS AP and the WDS station's local IP takes a long time to load, but in my tests there is no packet loss when I ping them. But I can tell that there is an initial delay before pings start coming back to my PC, which corresponds to the delay in accessing the AP's local IP address.
I know this is an unconventional and more complicated than average setup, but the question I have is:
Why does the CBR not like it when the AP has an external router/firewall but works just fine when the AP is connected to the modem via the WAN port and doing DHCP (taking the Ubiquiti out of the equation)? I technically should be able to have everything on the same subnet, correct?
Perhaps try to connect the AP device in a different way to the modem router.
- Leave WAN port and firewall in their default state on the AP device.
- Disable DCHP server on the AP
- use wires between a LAN port on the AP device and a LAN port on the modem-router.
This way you have made as few changes to the workings of the AP device as possible, but you will still have the same functionality, as if is was connected via the wan port etc. Only it is now on the same LAN as the modem-router device.
If they are using the same chipset (both Atheros or both Broadcom), use WDS.
After you set up WDS, on the WDS station, go to the Admin, Keep Alive tab, then enable the connection watchdog, put in the ip of the WDS AP, and 300 seconds.
Client bridge is not a transparent bridge, it is a hack in a way.