Hi,
I have two PPTP VPN servers (one at work, one in a data centre) that work perfectly. The only problem is that when I am at home, on my DD-WRT home network (Wi-Fi and wired), I can’t connect to these PPTP servers. The machines (debian laptop, android phones) that used to be able to connect to the VPN servers can’t do it from home.
I can SSH (custom port) and ping the machines that have the VPN servers just fine from inside the home network.
Google searching for this issue brings me tons of “how to setup a VPN server on your router”, which isn’t the problem at all. I have set up “VPN passthrough” : http://i.imgur.com/UoMwUoi.png (WAN IP changed between the screenshot and the posting of this link)
Any idea? Thanks !
I am just trying to understand your problem here.
Are the servers dd wrt too?
So you can connect to vpn from your phone using mobile data, but can’t connect as soon as you switch to wifi at home? You used a past perfect tense when talking about laptop and phone, so I am a bit confused.
I routinely connect to a dd wrt pptp server from my home network which again runs on dd wrt.
Sorry if I wasn’t clear. The servers are Debian (wheezy and jessie). When I am on mobile data or work Wi-Fi I can connect to the VPN, when I’m on home Wi-Fi I can’t. Same with the laptop: work wired or work Wi-Fi: VPN ok, home Wi-Fi or home wired: VPN not ok.
I suppose there’s a wrong setting in my router, which is a R7000 running dd-wrt. My ISP does not block VPN, as it used to work before I got the R7000.
Thanks!
Interesting.
There is one thing you could check. Is the range of ips assigned by home dhcp the same as your vpn server? It should be different. So if home assigns 192.168.1.xx, then vpn should assign something different, such as 192.168.25.xx.
Oh, I didn’t think of that, I’ll try and get back to you.
EDIT: I’m wrong, server does assign 192.168.0.x (but my home LAN is on 192.168.1.x) :
Jun 21 20:37:24 serveur pppd[15637]: local IP address 192.168.0.1
Jun 21 20:37:24 serveur pppd[15637]: remote IP address 192.168.0.5
Home assigns in the 192.168.1.xx, server assigns in the 164.xx.xx.xx, so no luck there 
If it helps, here are the logs :
on mobile network
Jun 21 20:54:47 penisland pppd[17068]: pppd 2.4.6 started by root, uid 0
Jun 21 20:54:47 penisland pppd[17068]: Using interface ppp0
Jun 21 20:54:47 penisland pppd[17068]: Connect: ppp0 <--> /dev/pts/1
Jun 21 20:54:53 penisland pppd[17068]: peer from calling number 81.x.x.x authorized
Jun 21 20:54:54 penisland pppd[17068]: MPPE 128-bit stateless compression enabled
Jun 21 20:54:54 penisland pppd[17068]: Cannot determine ethernet address for proxy ARP
Jun 21 20:54:54 penisland pppd[17068]: local IP address 192.168.0.1
Jun 21 20:54:54 penisland pppd[17068]: remote IP address 192.168.0.5
Jun 21 20:55:34 penisland pptpd[17067]: CTRL: EOF or bad error reading ctrl packet length.
Jun 21 20:55:34 penisland pptpd[17067]: CTRL: couldn't read packet header (exit)
Jun 21 20:55:34 penisland pptpd[17067]: CTRL: CTRL read failed
Jun 21 20:55:34 penisland pptpd[17067]: CTRL: Reaping child PPP[17068]
Jun 21 20:55:34 penisland pppd[17068]: Modem hangup
Jun 21 20:55:34 penisland pppd[17068]: Connect time 0.7 minutes.
Jun 21 20:55:34 penisland pppd[17068]: Sent 337780 bytes, received 126146 bytes.
Jun 21 20:55:34 penisland pppd[17068]: MPPE disabled
Jun 21 20:55:34 penisland pppd[17068]: Connection terminated.
Jun 21 20:55:34 penisland pppd[17068]: Exit.
Jun 21 20:55:34 penisland pptpd[17067]: CTRL: Client 81.x.x.x control connection finished
connecting to Wi-Fi on client
Jun 21 20:55:50 penisland pptpd[17264]: CTRL: Client 109.x.x.x control connection started
Jun 21 20:55:50 penisland pptpd[17264]: CTRL: Starting call (launching pppd, opening GRE)
Jun 21 20:55:50 penisland pppd[17265]: Plugin /usr/lib/pptpd/pptpd-logwtmp.so loaded.
Jun 21 20:55:50 penisland pppd[17265]: pppd 2.4.6 started by root, uid 0
Jun 21 20:55:50 penisland pppd[17265]: Using interface ppp0
Jun 21 20:55:50 penisland pppd[17265]: Connect: ppp0 <--> /dev/pts/1
Jun 21 20:56:20 penisland pppd[17265]: LCP: timeout sending Config-Requests
Jun 21 20:56:20 penisland pppd[17265]: Connection terminated.
Jun 21 20:56:21 penisland pppd[17265]: Modem hangup
Jun 21 20:56:21 penisland pppd[17265]: Exit.
Jun 21 20:56:21 penisland pptpd[17264]: GRE: read(fd=6,buffer=7f3f9ede3580,len=8196) from PTY failed: status = -1 error = Input/output error, usually caused by unexpected termination of pppd, check option syntax and pppd logs
Jun 21 20:56:21 penisland pptpd[17264]: CTRL: PTY read or GRE write failed (pty,gre)=(6,7)
Jun 21 20:56:21 penisland pptpd[17264]: CTRL: Reaping child PPP[17265]
Jun 21 20:56:21 penisland pptpd[17264]: CTRL: Client 109.x.x.x control connection finished
Ok I am out of ideas now. Maybe check work network’s netmask to see it doesn’t conflict with home network. Or change home network to something very different such as 192.168.129.x or 192.111.1.x
Also see how things work at a friend’s place using their wifi.
Let me know if you fix it, and how.
