F3726, F3211, F3174, R5135, R3816-HP Firewalls and UTM Devices VPN Configuration Guide-6PW100
11
• Tunnel interfaces using the same encapsulation protocol must have different source addresses and
destination addresses.
• If you configure a source interface for a tunnel interface, the tunnel interface takes the primary IP
address of the source interface as its source address.
• You can enable or disable the checksum function at both ends of a tunnel.
{ If checksum is enabled at the local end but not at the remote end, the local end calculates the
checksum of a packet to be sent but does not check the checksum of a received packet.
{ If checksum is enabled at the remote end but not at the local end, the local end checks the
checksum of a received packet but does not calculate the checksum of a packet to be sent.
• You can use the following methods to configure a route to a destination over the GRE tunnel:
{ Configure a static route, using the destination address of the original packet as the destination
address of the route and the address of the peer tunnel interface as the next hop.
{ Enable a dynamic routing protocol on both the tunnel interface and the interface connecting
the private network, so the dynamic routing protocol can establish a routing entry with the
tunnel interface as the outgoing interface.
• The IP address of the tunnel interface and the tunnel destination address configured on the tunnel
interface must be in different subnets.
333BConfiguration prerequisites
Configure an IP address for the interface (such as a VLAN interface, an Ethernet interface, or a Loopback
interface) to be used as the source interface of the tunnel interface.
334BConfiguration procedure
To configure a GRE over IPv4 tunnel:
Ste
p
Command
Remarks
1. Enter system view.
system-view N/A
2. Create a tunnel interface and
enter tunnel interface view.
interface tunnel interface-number
By default, a device has no tunnel
interface.
3. Configure an IPv4 address for
the tunnel interface.
ip address ip-address { mask |
mask-length }
By default, a tunnel interface has
no IPv4 address.
4. Set the tunnel mode to GRE
over IPv4.
tunnel-protocol gre
Optional.
The default tunnel mode is GRE
over IPv4.
You must configure the same tunnel
mode on both ends of a tunnel.
Otherwise, packet delivery will
fail.
5. Configure the source address
or interface for the tunnel
interface.
source { ip-address | interface-type
interface-number }
By default, no source address or
interface is configured for a tunnel
interface.
6. Configure the destination
address for the tunnel
interface.
destination ip-address
By default, no destination address
is configured for a tunnel interface.