OpenVPN Client: Error Connecting - IP/Routing Conflict (RT-AC68U / 380.62_1)

[Alex Tiedemann]

Hi,

I'm trying to figure out why OpenVPN clients in my AC68U have Routing Conflicts.

Have an AC68U connected to a Hitron router (from ISP), everything works great, except from the issue with OpenVPN clients in the AC68U.

AC68U have the following settings:
LAN: 192.168.1.1
SUB: 255.255.255.0
GW: 192.168.1.1
WINS: 192.168.1.1
DNS: 77.66.108.93
DNS: 91.214.71.181
DHCP: 192.168.1.21 - 192.168.1.254
Lease time: 86400

WAN: 192.168.0.2 (Static)
SUB: 255.255.255.240 (Only need few IP's here)
GW: 192.168.0.1
DNS: 77.66.108.93
DNS: 91.214.71.181

The Hitron router (CVE-30360):
LAN: 192.168.0.1
SUB: 255.255.255.240
DHCP: 192.168.0.5 - 192.168.0.14
AC68U is linked to it's MAC address and assigned 192.168.0.2.

OpenVPN Client in AC68U:
Have upgraded the firmware in AC68U (to 380.62_1), started from scratch, factory restore and had a clean start, so all settings have been done again.
When configuring the client, i find the config on my harddrive, upload it to the router, enter username, password, IP's to be routed via the client, apply the settings.
Initially things are working, and selected IP's are routed via OpenVPN in the router.

Then comes the issue, after changing the list of IP's to be routed via the client, and new settings are saved, i get the error message: Error - Routing conflict!
When looking at the VPN status page, Error connecting - IP/Routing conflict is shown.

Have tried to upload the config file with connection settings again, but still get the error message.
Also the error message shows when deleting the IP's added to the list for routing via VPN.

The only way to make a new connection, with the same OpenVPN client, is to change the server i connect to, then it works again. So if i change the norwegian vpn server to a finnish vpn server, i manage to connect and IP's are routed.

When changing the list of IP's to be routed, now with the finnish vpn server, the same error message shows, and then it works again, if i change to let's say a server in Holland.

When i look at the routing table, all previous servers are listed there, even though they are no longer in use, and every time i change the server, the routing table gets longer.
So somehow the routes seems to stay in the table.

Have attatched a couple of screen dumps to show what's going on.
The IP 10.8.20.0 in image 0002009 is when the vpn connection is made to one of the servers masked out.

Any ideas, anything i can try to change?


--
Kind regards,

Alex T.

 

[Martineau]

Hi,

I'm trying to figure out why OpenVPN clients in my AC68U have Routing Conflicts.

Have an AC68U connected to a Hitron router (from ISP), everything works great, except from the issue with OpenVPN clients in the AC68U.

AC68U have the following settings:
LAN: 192.168.1.1
SUB: 255.255.255.0
GW: 192.168.1.1
WINS: 192.168.1.1
DNS: 77.66.108.93
DNS: 91.214.71.181
DHCP: 192.168.1.21 - 192.168.1.254
Lease time: 86400

WAN: 192.168.0.2 (Static)
SUB: 255.255.255.240 (Only need few IP's here)
GW: 192.168.0.1
DNS: 77.66.108.93
DNS: 91.214.71.181

The Hitron router (CVE-30360):
LAN: 192.168.0.1
SUB: 255.255.255.240
DHCP: 192.168.0.5 - 192.168.0.14
AC68U is linked to it's MAC address and assigned 192.168.0.2.

OpenVPN Client in AC68U:
Have upgraded the firmware in AC68U (to 380.62_1), started from scratch, factory restore and had a clean start, so all settings have been done again.
When configuring the client, i find the config on my harddrive, upload it to the router, enter username, password, IP's to be routed via the client, apply the settings.
Initially things are working, and selected IP's are routed via OpenVPN in the router.

Then comes the issue, after changing the list of IP's to be routed via the client, and new settings are saved, i get the error message: Error - Routing conflict!
When looking at the VPN status page, Error connecting - IP/Routing conflict is shown.

Have tried to upload the config file with connection settings again, but still get the error message.
Also the error message shows when deleting the IP's added to the list for routing via VPN.

The only way to make a new connection, with the same OpenVPN client, is to change the server i connect to, then it works again. So if i change the norwegian vpn server to a finnish vpn server, i manage to connect and IP's are routed.

When changing the list of IP's to be routed, now with the finnish vpn server, the same error message shows, and then it works again, if i change to let's say a server in Holland.

When i look at the routing table, all previous servers are listed there, even though they are no longer in use, and every time i change the server, the routing table gets longer.
So somehow the routes seems to stay in the table.

Have attatched a couple of screen dumps to show what's going on.
The IP 10.8.20.0 in image 0002009 is when the vpn connection is made to one of the servers masked out.

Any ideas, anything i can try to change?


--
Kind regards,

Alex T.

View attachment 7602 View attachment 7603 View attachment 7605 View attachment 7606

http://www.snbforums.com/threads/op...service-state-apply-button.30410/#post-237935

 

[Mcavity]

Ok as a complete noob.. how do we run that code? just ssh and copy and paste?

 

[Martineau]

Ok as a complete noob.. how do we run that code? just ssh and copy and paste?

Yes, see the wiki for creation/use of scripts etc.

https://github.com/RMerl/asuswrt-merlin/wiki

 

[Alex Tiedemann]

Hi Mcavity,

The settings mentioned in my first post is something that can be done in the GUI via the browser.

What Martineau is linking to needs to be done via SSH.

I use WinSCP for windows as a SSH client.

When i get the error message about routing conflict, i SSH to the router and find the openvpn route in the routing table by typing route.
Here it would look something like:
vpn1.xxx.xxx.xxx 192.168.0.1 255.255.255.255 UGH 0 0 0 eth0

(See attatched screendump, have two openvpn routes here, both connected.)

Then i delete the route by typing: route del -net vpn1.xxx.xxx.xxx netmask 255.255.255.255 gw 192.168.0.1 dev eth0

(See attatched screendump.)

When the route has been deleted, i save the settings for the specific OpenVPN client in the router GUI.

vpn1.xxx.xxx.xxx is ofcourse the IP of the OpenVPN server.


--
Kind regards,

Alex T.

 

[Mcavity]

Thanks all! I have some homework for tonight..

 

[Mcavity]

ok heres an interesting bit of weirdness. winscp didnt seem to do anything.. and when i SSH to the router.. it closes the connection after a short period of time. about 90 seconds.

 

[Alex Tiedemann]

Hi Mcavity,

Have made a couple of screendumps to show you how my settings are.


--
Kind regards,

Alex T.