H3C Technologies H3C SecPath F1000-E - Manual (Page 22)

6
To do… Use the command… Remarks
Configure the source
address or interface for the
tunnel interface
source { ip-address | interface-type
interface-number }
Required
By default, no source address or
interface is configured for a tunnel
interface.
On each branch node, you need to
configure the tunnel destination
address as this source address.
Enable the GRE packet
checksum function
gre checksum
Optional
Disabled by default
For more information about the
GRE packet checksum function, see
GRE Security Options .
Configure a route for packet
forwarding through the
tunnel
See the IP Routing Volume.
Required
Each end of the tunnel must have a
route (static or dynamic) through
the tunnel to the other end.
Configure the aging time for
the tunnel entries
gre p2mp aging-time aging-time
Optional
5 seconds by default
Specify the backup interface
gre p2mp backup-interface
tunnel number
Optional
By default, no backup interface is
specified.
The backup interface must be an
existing tunnel interface that works
in GRE over IPv4 mode.
Configure the mask or mask
length of the private network
addresses of the branch
gre p2mp branch-network-mask
{ mask | mask-length }
Optional
By default, the mask of the private
network address of a branch is
255.255.255.255, that is, the
default mask length is 32.
Note that:
• For more information about tunnel interfaces and related configurations, see Tunneling
Configuration in the IP Services Volume.
• For information about commands interface tunnel, tunnel-protocol, and source, see
Tunneling Commands in the IP Services Volume.
• 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.