H3C Technologies H3C SR8800 - Manual (Page 347)

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Configuring IPv6 IS-IS
NOTE:
•
IPv6 IS-IS supports all IPv4 IS-IS features, but advertises IPv6 routing information. This document
describes only IPv6 IS-IS exclusive configuration tasks. For other configuration tasks, see the chapter
“Configuring IS-IS.”
• The term router in this document refers to both routers and Layer 3 switches.
Introduction to IPv6 IS-IS
The IS-IS routing protocol (Intermediate System-to-Intermediate System intra-domain routing information
exchange protocol) supports multiple network protocols, including IPv6. The international engineer task
force (IETF) defines two type-length-values (TLVs) and a new network layer protocol identifier (NLPID) to
enable IS-IS to support IPv6.
TLV is a variable-length field in the link state PDU or link state packet (LSP). The two TLVs are:
• IPv6 Reachability—Defines the prefix, metric of routing information to indicate network reachability,
and has a type value of 236 (0xEC).
• IPv6 Interface Address—Same as the “IP Interface Address” TLV in IPv4 ISIS, except that the 32-bit
IPv4 address is translated to the 128-bit IPv6 address.
The NLPID is an 8-bit field that identifies which network layer protocol is supported. For IPv6, the NLPID
is 142 (0x8E), which must be carried in hello packets sent by a router that supports IPv6 IS-IS.
For information about IS-IS, see the chapter “Configuring IS-IS.”
Configuring IPv6 IS-IS basic functions
NOTE:
You can implement IPv6 inter-networking through configuring IPv6 IS-IS in IPv6 network environment.
Configuration prerequisites
Before the configuration, complete the following tasks:
• Enable IPv6 globally.
• Configure IP addresses for interfaces, and make sure that all neighboring nodes are reachable to
each other.
• Enable IS-IS.
Configuration procedure
To configure the basic functions of IPv6 IS-IS: