0

I own two Synology NAS (at different places). The first one is set up as an OpenVPN server. All my devices(android mobile, windows pc, mac) work fine when connected to the synology VPN server but when i try to connect my second Synology to Synology VPN server although it appears connected it cannot ping the VPN site devices. The problem started back on 17 may 2021 (before that it was connected and worked fine), when suddenly all my devices couldn't connect to the vpn server so i deleted it and created it again, from then on i cannot make my second Synology nas ping other devices when connected vpn server. I deleted the whole nas and installed DSM and apps again but problem insist. Any ideas?

Azarias Spyridon Konstantinidi
  • 1
  • 1
  • Which configurations do you have? (You may mask out domain names, *public* IPs, keys.) What error messages/logs you have both on client and servers? How you determined you were actually "connected"? – Nikita Kipriyanov Jun 22 '21 at 07:43

1 Answers1

0

Thanks for your support.

At first place I think that I have to upload a simple network diagram to help, so here it is: Network Diagram - (begging=beginning)

I already opened a ticket to synology support. They told me they think the root cause is the routing policy. Originally, the traffic should be passed through the default gateway(which is the VPN gateway when it connects to VPN Server). But, the traffic destination is 192.168.1.0, this is the same as the VPN client local subnet,hence, when sending the packets to 192.168.1.0, it will send the packets via LAN interface instead of VPN.

After adding static routes in the VPN client, the VPN client could ping the VPN Servers machines with IP 192.168.1.0/24.

Also when changed the DS918+(VPN Client) LAN IP subnet mask (for example to 192.168.0.0/24) everything also worked fine.(After I changed the local subnet to 192.168.0.0/24, it is not the same as the target (192.168.1.0/24), so it will not check the local interface but directly go through the VPN interface.

They do not know why this happens but they will record this phenomenon and if they find out they will contact me

Azarias Spyridon Konstantinidi
  • 1
  • 1