Next: E-mail Up: VPN Previous: Router configuration Contents
The GRE4.7 protocol was developped by Cisco to encapsulate a multi variety of network layer protocols inside a specific IP tunnel. So the main idea was to create a link between Cisco routers, so two networks can stay interconnected (company headquarters and branchs for example). In these days the GRE protocol is Linux supported, so with GRE active at IPBrick, it's possible to create tunnels between IPBricks or between IPBricks and Cisco routers.
To set up a new GRE tunnel click Insert. The following options are available:
General settings
Name: GRE tunnel name;
Description: Description of the GRE connection;
State: GRE state - enable or disable.
Local Network Definitions
Local IP: IPBrick external interface address (eth1);
Server IP in local network: IPBrick internal interface address (eth0).
Remote network definitions
Remote IP: Remote IP address. Normally a public one because the tunnel is being established by Internet;
Remote subnet: Remote network address and mask;
A configuration example is shown at Figure 4.25
NOTE: When configuring a GRE tunnel between an IPBrick and a Cisco router, the Server IP in local network may need to be the local IP address of a GRE tunnel network, e.g.: GRE tunnel with specific network 10.0.0.0/24. IPBrick will have IP 10.0.0.1 and Cisco IP 10.0.0.2.
