I don’t know how the other various linux distros handle this but I found this by accident:
Nov 17 12:04:25 ukweb pppd[4943]: Using interface ppp0 Nov 17 12:04:25 ukweb pppd[4943]: Connect: ppp0 <--> /dev/pts/0 Nov 17 12:04:25 ukweb pptpd[4942]: GRE: Bad checksum from pppd. Nov 17 12:04:25 ukweb systemd-udevd[4944]: Using default interface naming scheme 'v249'. Nov 17 12:04:25 ukweb pppd[4943]: peer from calling number 1.1.1.1.1 authorized Nov 17 12:04:25 ukweb pppd[4943]: MPPE 128-bit stateless compression enabled Nov 17 12:04:27 ukweb systemd-networkd[592]: ppp0: Link UP Nov 17 12:04:27 ukweb systemd-networkd[592]: ppp0: Gained carrier Nov 17 12:04:27 ukweb pppd[4943]: found interface br0 for proxy arp Nov 17 12:04:27 ukweb pppd[4943]: local IP address 192.168.0.1 Nov 17 12:04:27 ukweb pppd[4943]: remote IP address 192.168.23.10 Nov 17 12:05:28 ukweb systemd[1]: Stopping PoPToP Point to Point Tunneling Server... Nov 17 12:05:28 ukweb pppd[4943]: Terminating on signal 15 Nov 17 12:05:28 ukweb pppd[4943]: Connect time 1.1 minutes. Nov 17 12:05:28 ukweb pppd[4943]: Sent 0 bytes, received 6937 bytes. Nov 17 12:05:28 ukweb systemd-networkd[592]: ppp0: Link DOWN Nov 17 12:05:28 ukweb systemd-networkd[592]: ppp0: Lost carrier
With the emphasis on “local IP address 192.168.0.1”. Which is *NOT* in my config. I went as far as adding a bridge to satisfy the proxy arp! Netplan is some yaml thing and yeah not a big fan.
ethernets:
eth0:
addresses:
- PUBLICIP/24
gateway4: GATEWAY
match:
macaddress: AA:BB:CC:00:00:01
nameservers:
addresses:
- 1.1.1.1
- 8.8.8.8
bridges:
br0:
dhcp4: no
addresses: [192.168.23.1/24]
version: 2
my /etc/ppp/pptpd.conf had the options set, but no matter what it *ALWAYS* went to 192.168.0.1
option /etc/ppp/pptpd-options
logwtmp
localip 192.168.24.1
remoteip 192.168.23.30-250
And then I found it after doing what i should have done, and grep around to find out that pptpd.conf should actually live in /etc
Yeah that’s right, there is 2 of them although they should be the same. A symlink and a restart later, and now I get this:
Nov 17 12:19:56 ukweb kernel: [ 112.718861] PPP MPPE Compression module registered Nov 17 12:19:56 ukweb pppd[1002]: MPPE 128-bit stateless compression enabled Nov 17 12:19:58 ukweb systemd-networkd[599]: ppp0: Link UP Nov 17 12:19:58 ukweb systemd-networkd[599]: ppp0: Gained carrier Nov 17 12:19:58 ukweb pppd[1002]: found interface br0 for proxy arp Nov 17 12:19:58 ukweb pppd[1002]: local IP address 192.168.23.1 Nov 17 12:19:58 ukweb pppd[1002]: remote IP address 192.168.23.10
MUCH much better. I don’t know if this is anything worth wriging about, but if I can save someone else an hour of wondering why the config isn’t working and why their pptp is always defaulting to 192.168.0.1 and why it’s wreaking havoc with any default home router, where here it is.
Use IPv6 and no longer have to worry about address conflicts at all.
Or you know, still enjoy my old stuff