RV042 as PPTP server

[Farhad Mustafayev]

Dear All,

I have PPTP server configured on RV042 and one Zyxel router which connects to Cisco as client.

There is no problem with connection itself. The problem is the follows:

Zyxel LAN clients can ping the LAN behind RV042 and RV042 itself (after adding an appropriate route in its config), but RV042 (being PPTP server) can't reach Zyxel itself and its LAN.

I've been trying to add different routes in Static Routing - no success, "Destination host unreachable" or "Request timed out".

All TCP, UDP and ICMP packets from anywhere are enabled on Zyxel.

What would you suggest?

[cchamorr]

Hello, 

I'm sorry you are having issues with the device.

It appears to me that you are trying to do something that the router was not meant for. On the RV042, when you configure the PPTO server is to allow access from remote devices to the LAN of the RV042, and it seems that functionality is working as expected.

It also appears you are trying to allow access to the devices behind the Zyxel router, and for this, you will need to create a Site to Site or Gateway to Gateway tunnel. Does the Zyxel have this capability?

In any case, it will be of great value if you can post the subnets behind all the devices.

Zyxel LAN:

RV042 LAN:

PPTP server address range:

What was the static route you created and on what device?

Please let us know.

[Farhad Mustafayev]

Dear cchamorr, thanks a lot for your response.

I also came to the mind, that "two way access" is not possible in my case.

In Zyxel KB (knowledge base) I found solution, where one Zyxel router works as PPTP server, another router connects to it as client and both of them has an access to each others LAN resources. So I supposed it will work as well for Cisco+Zyxel.

Zyxel LAN: 172.16.16.64/26 (where 172.16.16.126 is router itself)

RV042 LAN: 172.16.16.0/26 (where 172.16.16.62 is router itself)

PPTP: 172.16.16.55 - 172.16.16.59

Static route on RV042 ------ Dest. IP: 172.16.16.64, Subnet: 255.25.255.192, Default GW: 172.16.16.55, Interface: LAN. I also tried as default GW 172.16.16.126 and 172.16.16.62

Static route on Zyxel (it is really works) ---------- Dest. IP: 172.16.16.0, Subnet: 255.25.255.192, Default GW: 172.16.16.62, Interface: PPTP0.

Unfortunately this Zyxel doesn't have IPSEC tunneling feature, otherwise I would used Gateway to Gateway solution, which I successfully use to interconnect a RV042 routers. The only one reason of using Zyxel in my case - 3G USB support.

[cchamorr]

Hello, 

I'm sorry it has taken me so long to reply but this is a very busy day.

Now, I have to say that I'm very surprised that anything is working based on the information you provided.

In general, the RV042 is supported only to work with /24 subnets.

That being said, I think that you are experiencing more issues due to the fact that all of your subnets are 172.16.16.x.

Is it possible for you to change and use a completely different subnet on either side? I think this will be of great help for the router to understand were to send the traffic.

This is what I'm proposing:

1- Change the IP address of the RV042 to, lets say, 192.168.1.1

2- Then configure the PPTP server and you should setup the PPTP range as 192.168.1.200 - 192.168.1.204.

3- Then setup the connection from the Zyxel router to the new Ip address of the router and you should get connected with no problem.

4- When this works, check what is the IP address the Zyxel router is getting from the DHCP server and setup a static IP route on the Rv042 sending all the traffic destined for 172.16.16.x to the 192.168.1.x ip address the RV042 gave the Zyxel router for the PPTP connection.

I hope this helps.

[Farhad Mustafayev]

Hello,

Well, today I have finally won these routers! But using a different method.

I have configured Zyxel as transparent 3G bridge with 192.168.1.1/29 LAN connected to WAN1 port of RV042 with 172.16.16.64/26 LAN and Gateway to Gateway VPN tunnel to another RV042 (172.16.16.0/26). In this scenario everything works as I wished.

Regarding your wondering about /26 subnets not generally supported by RV042, I can assume you, that it works. I have 4 sites interconnected with each other by VPN tunnels using /26 subnets on both WAN and LAN. Moreover, one of them has dual WAN connection for remote administration and being connected to its PPTP server I have an access to all routers and their subnets.

Thank you for your proposal regarding 192.168.x.x/24, I tried it with the same result as before - one way pass.

[cchamorr]

Thank you for letting us know what you did to get it to work.

Have a nice day.