Can't connect to router from a client on VPN

VPN
1

I’ve setup a L2TP VPN on my Synology router (a RT6600ax). The VPN works great and when connected to it, I can access everything on my local network… except for the router itself. I can’t ping the router’s internal IP, I can’t open the router’s web UI, I can’t even access the router through the DS Router app on my iPhone (when that’s connected to the VPN).

The IP address my host receives is correct (192.168.0.xxx, my router’s internal LAN IP is 192.168.0.1). At the same time, if I connect to another machine on my local network (via say RDP, SSH, whatever), I can access the router’s WebUI through that with no problems.

I’ve been pouring over all of the settings on the router, in the Network Cnter, the main Control Panel, the VPN Plus Server and I can’t find anything which could help.

Does anyone have any ideas before I go insane? The router is running the latest SRM 1.3.1-9346 Update 2.

2

I have the exact same problem with L2TP, and I’m going insane also, I have never had a VPN setup with such frustration…

Can’t disable the Virtual IP setting for VPN, can’t access SRM but can access to other devices in the same subnet with the SRM.

3

SRM 1.3.1-9346 Update 3 here. Having the same issue. I believe this is a bug.

A workaround is to add a new firewall rule as below:

Protocol
TCP

Source
Network Interface: Internet (Yea it weird)
IP address: Specific IP > 192.168.1.0/24 (Don’t set All, otherwise everyone can connect to your router through WAN IP)
Ports: All

Destination
Network Interface: All
IP address: SRM
Ports: Custom > 8001

Action
Allow

4

Network center → Local Networks → choose network VPN client uses → Edit → first option “Allow managing Synology router

5

Yeah, and it’s almost impossible to search for this online :frowning: I have the feeling that it’s either a setting somewhere in SRM or just a bug.

I’ve kind of gone beyond this since I have access to everything else which includes a virtual machine I can use if I need to access SRM, plus I’ve pretty much got it setup and I’m not really messing with it anymore but its still annoying - especially since the iOS app also doesn’t work.

6

Cool, thanks for coming back here with this, I’ll try to give it a shot :slight_smile:

7

OMG this is working, the “Network Interface: Internet” did the magic, thanks a lot!

8

I don’t have any such option. The network the VPN client uses is my primary network - the same one all my other devices or on. It also gets an IP which is a part of this network.