H3C IS-IS配置2-DIS选择配置举例

1.组网需求

  Switch A、Switch B、Switch C和Switch D都运行IS-IS路由协议以实现互连，它们属于同一区域10，网络类型为广播网（以太网）。

  Switch A和Switch B是Level-1-2交换机，Switch C为Level-1交换机，Switch D为Level-2交换机。要求通过改变接口的DIS优先级，将Switch A配置为Level-1-2的DIS。

  

 2.配置步骤

  1）配置ISIS  

SW A
[SwitchA] isis 1
[SwitchA-isis-1] network-entity 10.0000.0000.0001.00
[SwitchA-isis-1] quit
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] isis enable 1

SW B
[SwitchB] isis 1
[SwitchB-isis-1] network-entity 10.0000.0000.0002.00
[SwitchB-isis-1] quit
[SwitchB] interface vlan-interface 100
[SwitchB-Vlan-interface100] isis enable 1

SW C
[SwitchC] isis 1
[SwitchC-isis-1] network-entity 10.0000.0000.0003.00
[SwitchC-isis-1] is-level level-1
[SwitchC-isis-1] quit
[SwitchC] interface vlan-interface 100
[SwitchC-Vlan-interface100] isis enable 1

SW D
[SwitchD] isis 1
[SwitchD-isis-1] network-entity 10.0000.0000.0004.00
[SwitchD-isis-1] is-level level-2
[SwitchD-isis-1] quit
[SwitchD] interface vlan-interface 100
[SwitchD-Vlan-interface100] isis enable 1

  2）查看当前配置  

# 查看Switch A的IS-IS邻居信息。
[SwitchA] display isis peer
                          Peer information for IS-IS(1)
                          ----------------------------
  System ID: 0000.0000.0002
  Interface: Vlan-interface100       Circuit Id: 0000.0000.0003.01
  State: Up     HoldTime: 21s        Type: L1(L1L2)     PRI: 64
  System ID: 0000.0000.0003
  Interface: Vlan-interface100       Circuit Id: 0000.0000.0003.01
  State: Up     HoldTime: 27s        Type: L1           PRI: 64
  System ID: 0000.0000.0002
  Interface: Vlan-interface100       Circuit Id: 0000.0000.0004.01
  State: Up     HoldTime: 28s        Type: L2(L1L2)     PRI: 64

  System ID: 0000.0000.0004

  Interface: Vlan-interface100       Circuit Id: 0000.0000.0004.01

  State: Up     HoldTime: 30s        Type: L2          PRI: 64  

# 显示Switch A的IS-IS接口信息。
[SwitchA] display isis interface
                       Interface information for IS-IS(1)
                       ----------------------------------
  Interface:  Vlan-interface100
  Index     IPv4 state      IPv6 state     Circuit ID   MTU   Type   DIS
  00001     Up              Down           1            1497  L1/L2  No/No

# 显示Switch C的IS-IS接口信息。
[SwitchC] display isis interface
                       Interface information for IS-IS(1)
                       ----------------------------------
  Interface:  Vlan-interface100
  Index     IPv4 state      IPv6 state     Circuit ID   MTU   Type   DIS
  00001     Up              Down           1            1497  L1/L2  Yes/No

# 显示Switch D的IS-IS接口信息。
[SwitchD] display isis interface
                       Interface information for IS-IS(1)
                       ----------------------------------
  Interface:  Vlan-interface100
  Index     IPv4 state      IPv6 state     Circuit ID   MTU   Type   DIS
  00001     Up              Down           1            1497  L1/L2  No/Yes

  从接口信息中可以看到，在使用缺省DIS优先级的情况下，Switch C为Level-1的DIS，Switch D为Level-2的DIS。Level-1和Level-2的伪节点分别是0000.0000.0003.01和0000.0000.0004.01。

3）修改DIS  

# 配置Switch A的DIS优先级。
[SwitchA] interface vlan-interface 100
[SwitchA-Vlan-interface100] isis dis-priority 100

# 查看Switch A的IS-IS邻居信息。
[SwitchA] display isis peer

                          Peer information for IS-IS(1)
                          ----------------------------
  System ID: 0000.0000.0002
  Interface: Vlan-interface100       Circuit Id: 0000.0000.0001.01
  State: Up     HoldTime: 21s        Type: L1(L1L2)     PRI: 64
  System ID: 0000.0000.0003
  Interface: Vlan-interface100       Circuit Id: 0000.0000.0001.01
  State: Up     HoldTime: 27s        Type: L1           PRI: 64
  System ID: 0000.0000.0002
  Interface: Vlan-interface100       Circuit Id: 0000.0000.0001.01
  State: Up     HoldTime: 28s        Type: L2(L1L2)     PRI: 64
  System ID: 0000.0000.0004
  Interface: Vlan-interface100       Circuit Id: 0000.0000.0001.01
  State: Up     HoldTime: 30s        Type: L2           PRI: 64

# 查看Switch A的IS-IS接口信息。
[SwitchA] display isis interface
                       Interface information for IS-IS(1)
                       ----------------------------------
  Interface:  Vlan-interface100
  Index     IPv4 state      IPv6 state     Circuit ID   MTU   Type   DIS
  00001     Up              Down           1            1497  L1/L2  Yes/Yes

  从上述信息中可以看到，在改变IS-IS接口的DIS优先级后，Switch A立即成为Level-1-2的DR（DIS），且伪节点是0000.0000.0001.01。