IS-IS通过新增TLV以实现对IPv6的支持
l 236号TLV
定义路由信息前缀、度量值等信息来说明网络的可达性
l 232号TLV
相当于IPv4中的“IP Interface Address”TLV，只不过把原来的32比特的IPv4地址改为128比特的IPv6地址
拓扑：
l 全网运行IS-IS；
l R1为Level-1路由器，NET地址为49.0012.0000.0000.0001.00；R2为Level-1-2路由器， NET地址为49.0012.0000.0000.0002.00；R3为Level-2路由器，NET地址为49.0003.0000.0000.0003.00；
l 将R3的环回口地址***到区域49.0012。
配置：
R1：
ipv6 //使能IPv6
isis 1
is-level level-1 //设置级别level-1
network-entity 49.0012.0000.0000.0001.00
#
ipv6 enable topology ipv6 // 使能ISIS多拓扑
interface GigabitEthernet0/0/0
ipv6 enable
ipv6 address 2012::1/64
isis ipv6 enable 1
isis circuit-level level-1
interface LoopBack0
ipv6 enable
ipv6 address 2111::1/128
isis ipv6 enable 1
R2：
ipv6
isis 1
network-entity 49.0012.0000.0000.0002.00
#
ipv6 enable topology ipv6
#
interface GigabitEthernet0/0/0
ipv6 enable
ipv6 address 2012::2/64
isis ipv6 enable 1
#
interface GigabitEthernet0/0/1
ipv6 enable
ipv6 address 2023::2/64
isis ipv6 enable 1
interface LoopBack0
ipv6 enable
ipv6 address 2222::2/128
isis ipv6 enable 1
R3：
ipv6
isis 1
network-entity 49.0003.0000.0000.0003.00
#
ipv6 enable topology ipv6
interface GigabitEthernet0/0/1
ipv6 enable
ipv6 address 2023::3/64
isis ipv6 enable 1
interface LoopBack0
ipv6 enable
ipv6 address 2333::3/128
isis ipv6 enable 1
验证：
[AR2]dis isis peer //查看IS-IS邻居
Peer information for ISIS(1)
System Id Interface Circuit Id State HoldTime Type PRI
-------------------------------------------------------------------------------
0000.0000.0001 GE0/0/0 0000.0000.0002.01 Up 30s L1 64
0000.0000.0003 GE0/0/1 0000.0000.0002.02 Up 22s L2(L1L2) 64
Total Peer(s): 2
[AR2]dis isis lsdb //查看IS-IS LSDB数据库
Database information for ISIS(1)
--------------------------------
Level-1 Link State Database
LSPID Seq Num Checksum Holdtime Length ATT/P/OL
-------------------------------------------------------------------------------
0000.0000.0001.00-00 0x00000003 0x5cf4 971 126 0/0/0
0000.0000.0002.00-00* 0x00000007 0xff2a 952 156 1/0/0
0000.0000.0002.01-00* 0x00000001 0xab1d 952 55 0/0/0
Total LSP(s): 3
*(In TLV)-Leaking Route, *(By LSPID)-Self LSP, +-Self LSP(Extended),
ATT-Attached, P-Partition, OL-Overload
Level-2 Link State Database
LSPID Seq Num Checksum Holdtime Length ATT/P/OL
-------------------------------------------------------------------------------
0000.0000.0002.00-00* 0x0000000d 0xfa5c 972 178 0/0/0
0000.0000.0002.01-00* 0x00000001 0xe90f 0 (748) 27 0/0/0
0000.0000.0002.02-00* 0x00000001 0xdce8 496 55 0/0/0
0000.0000.0003.00-00 0x00000009 0x12d2 747 126 0/0/0
0012.0000.0001.00-00 0x00000004 0xc190 709 124 0/0/0
Total LSP(s): 5
*(In TLV)-Leaking Route, *(By LSPID)-Self LSP, +-Self LSP(Extended),
ATT-Attached, P-Partition, OL-Overload
此时在R1上查看路由表，检查是否可以学习到R3的环回接口的明细路由。
[AR1]dis ipv routing-table protocol isis //查看ISIS路由表
Public Routing Table : ISIS
Summary Count : 3
ISIS Routing Table's Status : < Active >
Summary Count : 3
Destination : :: PrefixLength : 0
NextHop : FE80::2E0:FCFF:FE5D:4AD Preference : 15
Cost : 10 Protocol : ISIS-L1
RelayNextHop : :: TunnelID : 0x0
Interface : GigabitEthernet0/0/0 Flags : D
Destination : 2023:: PrefixLength : 64
NextHop : FE80::2E0:FCFF:FE5D:4AD Preference : 15
Cost : 20 Protocol : ISIS-L1
RelayNextHop : :: TunnelID : 0x0
Interface : GigabitEthernet0/0/0 Flags : D
Destination : 2222::2 PrefixLength : 128
NextHop : FE80::2E0:FCFF:FE5D:4AD Preference : 15
Cost : 10 Protocol : ISIS-L1
RelayNextHop : :: TunnelID : 0x0
Interface : GigabitEthernet0/0/0 Flags : D
ISIS Routing Table's Status : < Inactive >
Summary Count : 0
此时R1属于L1区域，不能学习到L2区域的R3 loopback0接口的明细路由。
需要在R2上针对L2区域的路由进行路由泄漏。
AR2：
isis 1
ipv6 import-route isis level-2 into level-1 //将L2的路由引入到L1中
[AR1]dis ipv routing-table protocol isis
Public Routing Table : ISIS
Summary Count : 4
ISIS Routing Table's Status : < Active >
Summary Count : 4
Destination : :: PrefixLength : 0
NextHop : FE80::2E0:FCFF:FE5D:4AD Preference : 15
Cost : 10 Protocol : ISIS-L1
RelayNextHop : :: TunnelID : 0x0
Interface : GigabitEthernet0/0/0 Flags : D
Destination : 2023:: PrefixLength : 64
NextHop : FE80::2E0:FCFF:FE5D:4AD Preference : 15
Cost : 20 Protocol : ISIS-L1
RelayNextHop : :: TunnelID : 0x0
Interface : GigabitEthernet0/0/0 Flags : D
Destination : 2222::2 PrefixLength : 128
NextHop : FE80::2E0:FCFF:FE5D:4AD Preference : 15
Cost : 10 Protocol : ISIS-L1
RelayNextHop : :: TunnelID : 0x0
Interface : GigabitEthernet0/0/0 Flags : D
Destination : 2333::3 PrefixLength : 128
NextHop : FE80::2E0:FCFF:FE5D:4AD Preference : 15
Cost : 20 Protocol : ISIS-L1
RelayNextHop : :: TunnelID : 0x0
Interface : GigabitEthernet0/0/0 Flags : D
ISIS Routing Table's Status : < Inactive >
Summary Count : 0