R3303-HP HSR6800 Routers Layer 3 - IP Services Configuration Guide

278
• On an HSR6802/HSR6804/HSR6808 router, you must execute the service command specify the
service card that forwards the traffic on the current interface. For more information about the service
command, see Layer 3—IP Services Command Reference.
• Two or more P2MP GRE tunnel interfaces cannot share the same source address.
• If you specify a source interface for a P2MP GRE 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 the 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 the checksum function 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.
• When configuring a route through the tunnel, you are not allowed to set up a static route whose
destination address is in the subnet of the tunnel interface. Instead, you can do one of the following:
{ Configure a static route, using the address of the subnet that the original packet is destined for
as its destination address and the address of the peer tunnel interface as its next hop.
{ Enable a dynamic routing protocol on both the tunnel interface and the router interface
connecting the private network, so that the dynamic routing protocol can establish a routing
entry that allows the tunnel to forward packets through the tunnel.
Configuration prerequisites
Configure an IP address for the interface to be used as the source interface of the tunnel interface (which
can be a, for example, VLAN interface, GigabitEthernet interface, or loopback interface), and make sure
this interface can communicate with the interface used as the source interface of the tunnel interface on
the peer device.
Configuration procedure
To configure a P2MP GRE 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 P2MP
GRE.
tunnel-protocol gre p2mp
In P2MP GRE tunnel mode, both
the transport protocol and
passenger protocol are IPv4.
You must configure the tunnel
mode as GRE over IPv4 on the
tunnel peers.