3Com MSR 50 Series, Руководство по настройке

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1594 C
HAPTER
81: GRE C
ONFIGURATION
Note that:
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For the configuration of MTU value, refer to the mtu command in “Tunneling
Configuration” on page 693 .
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The source address and destination address of a tunnel uniquely identify a
path. They must be configured at both ends of the tunnel and are mutually the
source address and the destination address.
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Two or more 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 source address of
the tunnel interface is the primary IP address of the source interface.
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If a device needs to reference a link aggregation group for the tunnel interface
to receive and send packets, the link aggregation group must already exist.
Otherwise, the tunnel interface cannot work properly and the tunnel cannot
communicate. For devices that do not support link aggregation, no link
aggregation group ID needs to be configured on the tunnel interface.
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You can enable or disable the checksum function at both ends of the tunnel as
needed. If the checksum function 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. Contrarily, 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.
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When you configure a route through the tunnel, you can configure a static
route, whose destination address is the destination address of the packet not
encapsulated in GRE and next hop is the address of the tunnel interface at the
remote end. Or, you can enable the 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. It is not allowed to set up a
static route whose destination address is in the subnet of the tunnel interface.
Configuring a GRE
over IPv6 Tunnel
Configuration
Prerequisites
Interfaces on a device, such as VLAN interfaces, Ethernet interfaces, and loopback
interfaces, are configured with IPv6 addresses and can communicate. These
interfaces can serve as the source of a virtual tunnel interface to ensure the
reachability of the destination address.
Configuration Procedure Follow these steps to configure a GRE over IPv6 tunnel:
To do... Use the command... Remarks
Enter system view system-view -
Enable the IPv6 packet
forwarding function ipv6 Required
Disabled by default