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Configuring IPv6 IS-IS 
Overview 
IPv6 IS-IS supports all IPv4 IS-IS features except that it advertises IPv6 routing information. This 
chapter describes only IPv6 IS-IS specific configuration tasks. For information about IS-IS, see 
"Configuring IS-IS."
 
Intermediate System-to-Intermediate System (IS-IS) supports multiple network protocols, including 
IPv6. To support IPv6, the IETF added two type-length-values (TLVs) and a new network layer 
protocol identifier (NLPID). 
The TLVs are as follows: 
• IPv6 Reachability—Contains routing prefix and metric information to describe 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 new 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 IPv6 IS-IS. 
Configuring basic IPv6 IS-IS 
Before you configure basic IPv6 IS-IS, complete the following tasks: 
•  Configure IPv6 addresses for interfaces to ensure IPv6 connectivity between neighboring 
nodes. 
•  Enable IS-IS. 
Basic IPv6 IS-IS configuration can implement the interconnection of IPv6 networks. 
To configure basic IPv6 IS-IS: 
 
Step  Command  Remarks 
1.  Enter system view. 
system-view 
N/A 
2.  Enable an IS-IS process and 
enter IS-IS view. 
isis
 [ process-id ] [ 
vpn-instance 
vpn-instance-name ] 
By default, no IS-IS process is 
enabled. 
3.  Configure the network entity 
title (NET) for the IS-IS 
process. 
network-entity
 net
 
By default, no NET is configured.
4.  Enable IPv6 for the IS-IS 
process. 
ipv6 enable 
The default setting is disabled. 
5.  Return to system view. 
quit 
N/A 
6.  Enter interface view. 
interface
 interface-type 
interface-number 
N/A 
7.  Enable IPv6 for IS-IS on the 
interface. 
isis ipv6 enable
 [ process-id ]  
By default, IPv6 is disabled for 
IS-IS on an interface. 
 
Configuring IPv6 IS-IS route control 
Before you configure IPv6 IS-IS route control, complete basic IPv6 IS-IS configuration.