Posted: Mon Sep 01, 2014 6:42 Post subject: PPTP mode won't use DHCP
I have a TP-Link TL-WDR4310 router, running DD-WRT v24-sp2, build 21061 (3/25/2013), which still shows that the stable release for this model. The router has worked great, but just started having issues.
I can use the router with static and auto configuration (DHCP) with no problem. However, I primarily use it to log on to my VPN. Whenever I select PPTP mode in the Setup tab, it seems to default to not using DHCP. I can select the Use DHCP Yes radio button, which removes the static IP fields in the GUI, but as soon as I click Save or Apply Settings, the manual IP fields are displayed, usually with my local IP address in the WAN IP address field, zeros in the subnet and 255.255.255.0 as the gateway.
I need to use the VPN DHCP to get a correct IP address for the tunnel. When I try to connect, I typically get a gateway IP address from the VPN, but the device address is still the local (192.168.0.x) one and the subnet is 0.0.0.0. The router then does not allow any LAN clients to connect to any external network.
Is there any other way to force the PPTP connection to use DHCP? (possibly from the command line). I have reflashed the router with the stable build file and done several 30-30-30 resets but continue to have the same problem. Is there a different build that I should try?
Thanks for the help. I did try the ssh commands, but without any change. I checked afterwards, and nvram show pptp_use_dhcp was 1.
I also tried updating to build 23919, which did help a little, but still didn't fix everything. The Setup tab now behaves as expected, showing Use DHCP as Yes, and without displaying the fields for the manual IP addresses. However, when I try to connect to VPN/PPTP, I still end up with my local router IP (192.168.0.3) and a subnet of 0.0.0.0, though the gateway seems to come from my VPN. I still cannot reach anything else online through this router. How can I force the PPTP connection to generate a new IP address? It would seem to be a firmware/software issue rather than a hardware problem with the device.
Yes, I'm sure that the provider requires DHCP. I am able to log on with any of several computers through my regular wifi connection, but I would prefer to have DD-WRT log on one time and let various devices (my family has 4 tablets, 4 phones, 2 computers and a gaming system) all connect through one persistent logon. (We live in a country where we all need VPN regularly).
The system has worked fine for over 6 months, but after the last time the main Internet connection dropped, I haven't been able to get the DD-WRT to use DHCP correctly. It seems to be doing everything else right, since the router shows me a gateway IP that shows a geolocation search at the VPN server, rather than my location. I wish I knew how to logon correctly, though why the problem persists after reflashing new firmware is puzzling.
I was running build 21061, which was fine until the last week or so. I have a friend running 20675 successfully on the same router, so I tried that, but had the same result (Use DHCP Yes, but the manual IP fields were displayed after every Save/Apply Settings). I am now using 23919.
