A Tip From Kinetic Computer Services ...
Setting Up VPN Tunnels on Cisco Linksys RV042 and RV082 Routers
Description of the Problem
You have a pair of Cisco Linksys small business routers, such as the RV042 or RV082. You would like to set up a VPN tunnel between them.
In a common scenario, you may have a server in your main office, and a remote site where there are some client computers that need to connect to the server. While setting up VPN connections on each computer in the remote office is possible, it often isn't practical.
Cisco Linksys small business routers such as the RV042 and RV082 allow the creation of VPN tunnels between them. This allows you to join two private local area networks (LANs) over the internet.
In order for this solution to work, at least one of your RV042/RV082 routers must be configured with a public, static IP address on the WAN interface. This would typically be done at the main office, but it makes no difference as far as the router configuration goes.
The following values are used in our sample configuration below:
Log on to the router configuration utility. Select the VPN tab, then click the button to Add a VPN tunnel. The type of tunnel you are adding is Gateway-to-Gateway. Enter the following values:
After you add the above configuration to the routers, you can press the "Connect" button on the VPN Summary page of the remote office router. If all goes well, the tunnel status will change to "Connected". Your tunnel is now up, and your local area networks are now connected! The computers in your remote office should be able to ping and connect to the server in your home office, provided you don't have any policies or rules in the way. There is no need to add static routes or configure any additional routing between the two networks; the VPN tunnel does that for you.
If the tunnel doesn't connect, or doesn't stay connected, look at the router's system logs. One message you may see reads "Dynamic VPN client in Main Mode is only supported for Microsoft VPN client, please use Aggressive mode instead." To fix this error, edit your tunnel and click the Advanced button at the bottom of the IPSec Setup section. Make sure the "Aggressive Mode" checkbox is checked.
You may also see the following error message: "Initial Aggressive Mode message from x.x.x.x but no (wildcard) connection has been configured." Be aware that this error can have many causes. If you see it, first check your VPN tunnel configurations to make sure that you have entered the correct values. If they are correct and the error persists, simply delete the tunnel and add it back in. Believe me, this fixes the problem pretty often! If you've done that and the error still persists, update the firmware on both routers and try again. Note that it is not necessary for both routers to be of the same model, hardware version, or firmware version.
If both routers have static IP's, you can configure both ends of the tunnel to be static, if you wish.
Posted on May 7, 2012
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