H3C Technologies H3C SecPath F1000-E - Manual (Page 61)

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Figure 52 Verifying the configuration result on SecPath A (3)
Configuring a P2MP GRE tunnel at the CLI
Configuration guidelines
• 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 as needed. 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. In contrast, 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 network segment 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
On each of the peer devices, 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 that this interface can communicate with the interface used as the
source interface of the tunnel interface on the peer device normally.
Configuration procedure
To configure a P2MP GRE tunnel: