请教大佬们，VLAN100，200，300这3个vlan怎么配置都变成VLAN400访问？

您好，请知：

配置vlan映射就好，以下是配置案例，请参考：

1.6  VLAN映射典型配置举例

1.6.1  1:1和N:1 VLAN映射配置举例

1. 组网需求

·     在某小区，服务提供商为每个家庭都提供了PC、VoD和VoIP这三种数据服务，每个家庭都通过各自的家庭网关接入楼道交换机，并通过DHCP方式自动获取IP地址。

·     服务提供商希望实现以下网络规划：在家庭网关上，分别将PC、VoD和VoIP业务依次划分到VLAN 1～3；在楼道交换机上，为了隔离不同家庭的同类业务，将每个家庭的每种业务都划分到不同的VLAN；而在园区交换机上，为了节省VLAN资源，将所有家庭的同类业务都划分到相同的VLAN，即分别将PC、VoD和VoIP业务依次划分到VLAN 501～503。

2. 组网图

图1-11 1:1和N:1 VLAN映射配置组网图

3. 配置步骤

(1)     配置Switch A

# 配置下行端口GigabitEthernet1/0/1和GigabitEthernet1/0/2为Trunk端口且允许原始VLAN及转换后VLAN通过，同时在端口上配置1:1 VLAN映射。

<SwitchA> system-view

[SwitchA] vlan 2 to 3

[SwitchA] vlan 101 to 102

[SwitchA] vlan 201 to 202

[SwitchA] vlan 301 to 302

[SwitchA] interface gigabitethernet 1/0/1

[SwitchA-GigabitEthernet1/0/1] port link-type trunk

[SwitchA-GigabitEthernet1/0/1] port trunk permit vlan 1 2 3 101 201 301

[SwitchA-GigabitEthernet1/0/1] vlan mapping 1 translated-vlan 101

[SwitchA-GigabitEthernet1/0/1] vlan mapping 2 translated-vlan 201

[SwitchA-GigabitEthernet1/0/1] vlan mapping 3 translated-vlan 301

[SwitchA-GigabitEthernet1/0/1] quit

[SwitchA] interface gigabitethernet 1/0/2

[SwitchA-GigabitEthernet1/0/2] port link-type trunk

[SwitchA-GigabitEthernet1/0/2] port trunk permit vlan 1 2 3 102 202 302

[SwitchA-GigabitEthernet1/0/2] vlan mapping 1 translated-vlan 102

[SwitchA-GigabitEthernet1/0/2] vlan mapping 2 translated-vlan 202

[SwitchA-GigabitEthernet1/0/2] vlan mapping 3 translated-vlan 302

[SwitchA-GigabitEthernet1/0/2] quit

# 配置上行端口GigabitEthernet1/0/3为Trunk端口，且允许转换后VLAN通过。

[SwitchA] interface gigabitethernet 1/0/3

[SwitchA-GigabitEthernet1/0/3] port link-type trunk

[SwitchA-GigabitEthernet1/0/3] port trunk permit vlan 101 201 301 102 202 302

[SwitchA-GigabitEthernet1/0/3] quit

(2)     配置Switch B

Switch B的配置与Switch A相似，配置过程略。

(3)     配置Switch C

# 使能DHCP Snooping功能。

<SwitchC> system-view

[SwitchC] dhcp snooping enable

# 创建原始VLAN和转换后VLAN，并在这些VLAN上分别使能ARP Detection功能。

[SwitchC] vlan 101

[SwitchC-vlan101] arp detection enable

[SwitchC-vlan101] vlan 201

[SwitchC-vlan201] arp detection enable

[SwitchC-vlan201] vlan 301

[SwitchC-vlan301] arp detection enable

[SwitchC-vlan301] vlan 102

[SwitchC-vlan102] arp detection enable

[SwitchC-vlan102] vlan 202

[SwitchC-vlan202] arp detection enable

[SwitchC-vlan202] vlan 302

[SwitchC-vlan302] arp detection enable

[SwitchC-vlan302] vlan 103

[SwitchC-vlan103] arp detection enable

[SwitchC-vlan103] vlan 203

[SwitchC-vlan203] arp detection enable

[SwitchC-vlan203] vlan 303

[SwitchC-vlan303] arp detection enable

[SwitchC-vlan303] vlan 104

[SwitchC-vlan104] arp detection enable

[SwitchC-vlan104] vlan 204

[SwitchC-vlan204] arp detection enable

[SwitchC-vlan204] vlan 304

[SwitchC-vlan304] arp detection enable

[SwitchC-vlan304] vlan 501

[SwitchC-vlan501] arp detection enable

[SwitchC-vlan501] vlan 502

[SwitchC-vlan502] arp detection enable

[SwitchC-vlan502] vlan 503

[SwitchC-vlan503] arp detection enable

[SwitchC-vlan503] quit

# 配置下行端口GigabitEthernet1/0/1和GigabitEthernet1/0/2为Trunk端口且允许原始VLAN及转换后VLAN通过，同时在端口上配置N:1 VLAN映射，并启用DHCP Snooping表项记录功能。

[SwitchC] interface gigabitethernet 1/0/1

[SwitchC-GigabitEthernet1/0/1] port link-type trunk

[SwitchC-GigabitEthernet1/0/1] port trunk permit vlan 101 102 201 202 301 302 501 to 503

[SwitchC-GigabitEthernet1/0/1] vlan mapping uni range 101 to 102 translated-vlan 501

[SwitchC-GigabitEthernet1/0/1] vlan mapping uni range 201 to 202 translated-vlan 502

[SwitchC-GigabitEthernet1/0/1] vlan mapping uni range 301 to 302 translated-vlan 503

[SwitchC-GigabitEthernet1/0/1] dhcp snooping binding record

[SwitchC-GigabitEthernet1/0/1] quit

[SwitchC] interface gigabitethernet 1/0/2

[SwitchC-GigabitEthernet1/0/2] port link-type trunk

[SwitchC-GigabitEthernet1/0/2] port trunk permit vlan 103 104 203 204 303 304 501 to 503

[SwitchC-GigabitEthernet1/0/2] vlan mapping uni range 103 to 104 translated-vlan 501

[SwitchC-GigabitEthernet1/0/2] vlan mapping uni range 203 to 204 translated-vlan 502

[SwitchC-GigabitEthernet1/0/2] vlan mapping uni range 303 to 304 translated-vlan 503

[SwitchC-GigabitEthernet1/0/2] dhcp snooping binding record

[SwitchC-GigabitEthernet1/0/2] quit

# 在上行端口GigabitEthernet1/0/3上配置网络侧N:1 VLAN映射。

[SwitchC] interface gigabitethernet 1/0/3

[SwitchC-GigabitEthernet1/0/3] vlan mapping nni

# 配置端口GigabitEthernet1/0/3为Trunk端口且允许转换后VLAN通过，并配置该端口为DHCP Snooping信任端口和ARP信任端口。

[SwitchC-GigabitEthernet1/0/3] port link-type trunk

[SwitchC-GigabitEthernet1/0/3] port trunk permit vlan 501 to 503

[SwitchC-GigabitEthernet1/0/3] dhcp snooping trust

[SwitchC-GigabitEthernet1/0/3] arp detection trust

[SwitchC-GigabitEthernet1/0/3] quit

(4)     配置Switch D

# 配置端口GigabitEthernet1/0/1为Trunk端口且允许转换后VLAN通过。

<SwitchD> system-view

[SwitchD] vlan 501 to 503

[SwitchD] interface gigabitethernet 1/0/1

[SwitchD-GigabitEthernet1/0/1] port link-type trunk

[SwitchD-GigabitEthernet1/0/1] port trunk permit vlan 501 to 503

[SwitchD-GigabitEthernet1/0/1] quit

4. 验证配置

(1)     查看Switch A上的VLAN映射配置信息

[SwitchA] display vlan mapping

Interface GigabitEthernet1/0/1:

  Outer VLAN    Inner VLAN    Translated Outer VLAN    Translated Inner VLAN

  1             N/A           101                      N/A

  2             N/A           201                      N/A

  3             N/A           301                      N/A

Interface GigabitEthernet1/0/2:

  Outer VLAN    Inner VLAN    Translated Outer VLAN    Translated Inner VLAN

  1             N/A           102                      N/A

  2             N/A           202                      N/A

  3             N/A           302                      N/A

(2)     查看Switch B上的VLAN映射配置信息

Switch B上的VLAN映射配置信息与Switch A相似，显示信息略。

(3)     查看Switch C上的VLAN映射配置信息

[SwitchC] display vlan mapping

Interface GigabitEthernet1/0/1:

  Outer VLAN    Inner VLAN    Translated Outer VLAN    Translated Inner VLAN

  101-102       N/A           501                      N/A

  201-202       N/A           502                      N/A

  301-302       N/A           503                      N/A

Interface GigabitEthernet1/0/2:

  Outer VLAN    Inner VLAN    Translated Outer VLAN    Translated Inner VLAN

  103-104       N/A           501                      N/A

  203-204       N/A           502                      N/A

  303-304       N/A           503                      N/A

以上信息表明，Switch A和Switch B上的1:1 VLAN映射，以及Switch C上的N:1 VLAN映射配置成功。

1.6.2  1:2和2:2 VLAN映射配置举例

1. 组网需求

·     VPN A中的Site 1和Site 2是某公司的两个分支机构，且分别利用VLAN 5和VLAN 6承载业务。由于分处不同地域，这两个分支机构采用了不同的SP所提供的VPN接入服务，SP 1和SP 2分别将VLAN 100和VLAN 200分配给这两个分支机构使用。

·     该公司希望其下属的这两个分支机构可以跨越SP 1和SP 2的网络实现互通。

2. 组网图

图1-12 1:2和2:2 VLAN映射配置组网图

3. 配置步骤

(1)     配置PE 1

# 在下行端口GigabitEthernet1/0/1上配置1:2 VLAN映射，为VLAN 5的报文添加VLAN 100的外层VLAN Tag。

<PE1> system-view

[PE1] interface gigabitethernet 1/0/1

[PE1-GigabitEthernet1/0/1] vlan mapping nest single 5 nested-vlan 100

# 配置GigabitEthernet1/0/1为Hybrid端口且允许VLAN 100的报文不携带VLAN Tag通过。

[PE1-GigabitEthernet1/0/1] port link-type hybrid

[PE1-GigabitEthernet1/0/1] port hybrid vlan 100 untagged

[PE1-GigabitEthernet1/0/1] quit

# 配置上行端口GigabitEthernet1/0/2为Trunk端口且允许VLAN 100通过。

[PE1] interface gigabitethernet 1/0/2

[PE1-GigabitEthernet1/0/2] port link-type trunk

[PE1-GigabitEthernet1/0/2] port trunk permit vlan 100

[PE1-GigabitEthernet1/0/2] quit

(2)     配置PE 2

# 配置端口GigabitEthernet1/0/1为Trunk端口且允许VLAN 100通过。

<PE2> system-view

[PE2] interface gigabitethernet 1/0/1

[PE2-GigabitEthernet1/0/1] port link-type trunk

[PE2-GigabitEthernet1/0/1] port trunk permit vlan 100

[PE2-GigabitEthernet1/0/1] quit

# 配置端口GigabitEthernet1/0/2为Trunk端口且允许VLAN 100通过。

[PE2] interface gigabitethernet 1/0/2

[PE2-GigabitEthernet1/0/2] port link-type trunk

[PE2-GigabitEthernet1/0/2] port trunk permit vlan 100

[PE2-GigabitEthernet1/0/2] quit

(3)     配置PE 3

# 配置端口GigabitEthernet1/0/1为Trunk端口且允许VLAN 100和200通过。

<PE3> system-view

[PE3] interface gigabitethernet 1/0/1

[PE3-GigabitEthernet1/0/1] port link-type trunk

[PE3-GigabitEthernet1/0/1] port trunk permit vlan 100 200

# 在端口GigabitEthernet1/0/1上配置2:2 VLAN映射，将外层VLAN为100、内层VLAN为5的报文的VLAN ID转换为外层VLAN为200、内层VLAN为6。

[PE3-GigabitEthernet1/0/1] vlan mapping tunnel 100 5 translated-vlan 200 6

[PE3-GigabitEthernet1/0/1] quit

# 配置端口GigabitEthernet1/0/2为Trunk端口且允许VLAN 200通过。

[PE3] interface gigabitethernet 1/0/2

[PE3-GigabitEthernet1/0/2] port link-type trunk

[PE3-GigabitEthernet1/0/2] port trunk permit vlan 200

[PE3-GigabitEthernet1/0/2] quit

(4)     配置PE 4

# 配置上行端口GigabitEthernet1/0/1为Trunk端口且允许VLAN 200通过。

<PE4> system-view

[PE4] interface gigabitethernet 1/0/1

[PE4-GigabitEthernet1/0/1] port link-type trunk

[PE4-GigabitEthernet1/0/1] port trunk permit vlan 200

[PE4-GigabitEthernet1/0/1] quit

# 配置下行端口GigabitEthernet1/0/2为Hybrid端口且允许VLAN 200的报文不携带VLAN Tag通过。

[PE4] interface gigabitethernet 1/0/2

[PE4-GigabitEthernet1/0/2] port link-type hybrid

[PE4-GigabitEthernet1/0/2] port hybrid vlan 200 untagged

# 在端口GigabitEthernet1/0/2上配置1:2 VLAN映射，为VLAN 6的报文添加VLAN 200的外层VLAN Tag。

[PE4-GigabitEthernet1/0/2] vlan mapping nest single 6 nested-vlan 200

[PE4-GigabitEthernet1/0/2] quit

4. 验证配置

(1)     查看PE 1上的VLAN映射配置信息

[PE1] display vlan mapping

Interface GigabitEthernet1/0/1:

  Outer VLAN    Inner VLAN    Translated Outer VLAN    Translated Inner VLAN

  5             N/A           100                      5

(2)     查看PE 3上的VLAN映射配置信息

[PE3] display vlan mapping

Interface GigabitEthernet1/0/1:

  Outer VLAN    Inner VLAN    Translated Outer VLAN    Translated Inner VLAN

  100           5             200                      6

(3)     查看PE 4上的VLAN映射配置信息

[PE4] display vlan mapping

Interface GigabitEthernet1/0/2:

  Outer VLAN    Inner VLAN    Translated Outer VLAN    Translated Inner VLAN

  6             N/A           200                      6

以上信息表明，PE 1和PE 4上的1:2 VLAN映射，以及PE 3上的2:2 VLAN映射配置成功。