Proroute
GEM
2M
4G
Router
GEM-2M series User Manual
103
“Peer Subnet” option here. When “Default Gateway” is chosen, all traffic from
Intranet of Business Security Gateway goes over this GRE tunnel if these
packets don’t match the Peer Subnet of other GRE tunnels. There is only one
GRE tunnel to own the “Default Gateway” property. However, when “Peer
Subnet” is chosen, peer subnet parameter needs to be filled and it should be the
LAN subnet of remote GRE server. If an Intranet packet wants to go to this peer
subnet, the GRE tunnel will be established automatically.
3.2.4 Redundancy
3.2.4.1 VRRP
The Virtual Router Redundancy Protocol (VRRP) is a computer networking protocol
providing device redundancy. It allows a backup router or switch to automatically take
over if the primary (master) router or switch fails. This increases the availability and
reliability of routing paths via automatic default gateway selections on an IP network.
The protocol achieves this by creation of virtual routers, which are an abstract
representation of multiple routers, i.e. master and backup routers, acting as a group.
The default gateway of a participating host is assigned to the virtual router instead of
a physical router. If the physical router that is routing packets on behalf of the virtual
router fails, another physical router is selected to automatically replace it. The
physical router that is forwarding packets at any given time is called the master router.
