Contents

Configuring IPv6 multicast VLANs· 1

Overview· 1

IPv6 multicast VLAN configuration task list 3

Configuring a sub-VLAN-based IPv6 multicast VLAN· 3

Configuration prerequisites· 3

Configuration guidelines· 3

Configuration procedure· 3

Configuring a port-based IPv6 multicast VLAN· 4

Configuration prerequisites· 4

Configuring user port attributes· 4

Assigning user ports to an IPv6 multicast VLAN· 4

Setting the maximum number of IPv6 multicast VLAN forwarding entries· 5

Displaying and maintaining IPv6 multicast VLANs· 5

IPv6 multicast VLAN configuration examples· 6

Sub-VLAN-based IPv6 multicast VLAN configuration example· 6

Port-based IPv6 multicast VLAN configuration example· 9

 

Configuring IPv6 multicast VLANs

Overview

As shown in Figure 1, Host A, Host B, and Host C are in different VLANs and the same IPv6 multicast group. When Switch A (Layer 3 device) receives IPv6 multicast data for that group, it sends three copies of the data to Switch B (Layer 2 device). This occupies a large amount of bandwidth and increases the burden on the Layer 3 device.

Figure 1 Multicast transmission without the IPv6 multicast VLAN feature

 

After an IPv6 multicast VLAN is configured on Switch B, Switch A sends one copy of the IPv6 multicast data to the IPv6 multicast VLAN on Switch B. This saves network bandwidth and lessens the burden on the Layer 3 device.

IPv6 multicast VLANs include sub-VLAN-based IPv6 multicast VLANs and port-based IPv6 multicast VLANs.

Sub-VLAN-based IPv6 multicast VLAN

As shown in Figure 2:

·           Host A, Host B, and Host C are in VLAN 2 through VLAN 4, respectively.

·           On Switch B, VLAN 10 is an IPv6 multicast VLAN.

VLAN 2 through VLAN 4 are sub-VLANs of VLAN 10.

MLD snooping is enabled for the multicast VLAN and its sub-VLANs.

Figure 2 Sub-VLAN-based multicast VLAN

 

MLD snooping manages router ports in the IPv6 multicast VLAN and member ports in each sub-VLAN. When Switch A receives IPv6 multicast data from the multicast source, it sends only one copy of the IPv6 multicast data to the IPv6 multicast VLAN on Switch B. Then, Switch B sends a separate copy to each sub-VLAN of the IPv6 multicast VLAN.

Port-based IPv6 multicast VLAN

As shown in Figure 3:

·           Host A, Host B, and Host C are in VLAN 2 through VLAN 4, respectively.

·           On Switch B, VLAN 10 is an IPv6 multicast VLAN.

All the user ports are hybrid ports and are assigned to VLAN 10.

MLD snooping is enabled for the IPv6 multicast VLAN and VLAN 2 through VLAN 4.

Figure 3 Port-based IPv6 multicast VLAN

 

MLD snooping manages the router ports and member ports in the IPv6 multicast VLAN. When Switch A receives IPv6 multicast data from the multicast source, it sends only one copy of the IPv6 multicast data to the IPv6 multicast VLAN on Switch B. Then, Switch B sends a separate copy to each user port in the IPv6 multicast VLAN.

IPv6 multicast VLAN configuration task list

Tasks at a glance
(Required.) Perform one of the following tasks: ·          Configuring a sub-VLAN-based IPv6 multicast VLAN ·          Configuring a port-based IPv6 multicast VLAN ¡  Configuring user port attributes ¡  Assigning user ports to an IPv6 multicast VLAN
(Optional.) Setting the maximum number of IPv6 multicast VLAN forwarding entries

 

If you have configured both a sub-VLAN-based IPv6 multicast VLAN and a port-based IPv6 multicast VLAN on a device, the port-based IPv6 multicast VLAN configuration takes effect.

Configuring a sub-VLAN-based IPv6 multicast VLAN

You must first configure a VLAN as an IPv6 multicast VLAN, and then assign the VLANs that contain multicast receivers to the IPv6 multicast VLAN as sub-VLANs.

Configuration prerequisites

Before you configure a sub-VLAN-based IPv6 multicast VLAN, complete the following tasks:

·           Create VLANs as required.

·           Enable MLD snooping for the VLAN to be configured as the IPv6 multicast VLAN, and for the VLANs to be configured as sub-VLANs.

Configuration guidelines

When you configure a sub-VLAN-based IPv6 multicast VLAN, follow these guidelines:

·           The VLAN to be configured as the IPv6 multicast VLAN must exist.

·           A VLAN to be configured as a sub-VLAN must exist and must not be an IPv6 multicast VLAN or a sub-VLAN of any other IPv6 multicast VLANs.

·           The total number of IPv6 multicast VLANs on a device must not exceed the upper limit.

Configuration procedure

To configure a sub-VLAN-based IPv6 multicast VLAN:

 

Step	Command	Remarks
1.      Enter system view.	system-view	N/A
2.      Configure a VLAN as an IPv6 multicast VLAN and enter its view.	ipv6 multicast-vlan vlan-id	By default, a VLAN is not an IPv6 multicast VLAN.
3.      Assign the specified VLANs to the IPv6 multicast VLAN as sub-VLANs.	subvlan vlan-list	By default, an IPv6 multicast VLAN does not have any sub-VLANs.

 

Configuring a port-based IPv6 multicast VLAN

To configure a port-based IPv6 multicast VLAN, perform the following steps:

1.      Configure a VLAN as an IPv6 multicast VLAN.

2.      Configure the attributes for user ports that are connected to the multicast receivers.

3.      Assign the user ports to the IPv6 multicast VLAN.

You can assign a port to an IPv6 multicast VLAN only when the port is an Ethernet port or a Layer 2 aggregate interface.

Configuration prerequisites

Before you configure a port-based IPv6 multicast VLAN, complete the following tasks:

·           Create VLANs as required.

·           Enable MLD snooping for the VLAN to be configured as the IPv6 multicast VLAN.

·           Enable MLD snooping for all the VLANs that contain the multicast receivers.

Configuring user port attributes

Step	Command	Remarks
1.      Enter system view.	system-view	N/A
2.      Enter interface view.	interface interface-type interface-number	N/A
3.      Configure the link type of the user port as hybrid.	port link-type hybrid	The default setting is access. For more information about this command, see Layer 2—LAN Switching Command Reference.
4.      Specify the PVID of the current user port as the VLAN to which the user port belongs.	port hybrid pvid vlan vlan-id	By default, the PVID for a hybrid port is VLAN 1. For more information about this command, see Layer 2—LAN Switching Command Reference.
5.      Configure the current user port to permit IPv6 multicast VLAN and to untag the packets.	port hybrid vlan vlan-id-list untagged	By default, a hybrid port permits only VLAN 1. For more information about this command, see Layer 2—LAN Switching Command Reference.

 

Assigning user ports to an IPv6 multicast VLAN

You can either assign the user ports to the IPv6 multicast VLAN in IPv6 multicast VLAN view, or assign the user ports to the IPv6 multicast VLAN in interface view.

When you perform this task, follow these guidelines:

·           The VLAN to be configured as an IPv6 multicast VLAN must exist.

·           A port can belong to only one IPv6 multicast VLAN.

Assigning ports to an IPv6 multicast VLAN in IPv6 multicast VLAN view

Step	Command	Remarks
1.      Enter system view.	system-view	N/A
2.      Configure an IPv6 VLAN as an IPv6 multicast VLAN and enter its view.	ipv6 multicast-vlan vlan-id	By default, a VLAN is not an IPv6 multicast VLAN.
3.      Assign ports to the IPv6 multicast VLAN.	port interface-list	By default, an IPv6 multicast VLAN does not have any user ports.

 

Assigning a port to an IPv6 multicast VLAN in interface view

Step	Command	Remarks
1.      Enter system view.	system-view	N/A
2.      Configure an IPv6 VLAN as an IPv6 multicast VLAN and enter its view.	ipv6 multicast-vlan vlan-id	By default, a VLAN is not an IPv6 multicast VLAN.
3.      Return to system view.	quit	N/A
4.      Enter interface view.	interface interface-type interface-number	N/A
5.      Assign the current port to the IPv6 multicast VLAN.	ipv6 port multicast-vlan vlan-id	By default, a user port does not belong to any IPv6 multicast VLAN.

 

Setting the maximum number of IPv6 multicast VLAN forwarding entries

You can set the maximum number of IPv6 multicast VLAN forwarding entries on the device. When the upper limit is reached, the device does not create IPv6 multicast VLAN forwarding entries until some entries age out or are manually removed.

If the total number of entries exceeds the upper limit value that you are setting, the system does not automatically remove existing entries or create new entries. As a best practice, remove excess entries manually.

To set the maximum number of IPv6 multicast VLAN forwarding entries:

 

Step	Command	Remarks
1.      Enter system view.	system-view	N/A
2.      Set the maximum number of IPv6 multicast VLAN forwarding entries.	ipv6 multicast-vlan entry-limit limit	The default setting is 128.

 

Displaying and maintaining IPv6 multicast VLANs

Execute display commands in any view and reset commands in user view.

 

Task	Command
Display information about IPv6 multicast VLANs.	display ipv6 multicast-vlan [ vlan-id ]
Display information about IPv6 multicast groups in IPv6 multicast VLANs.	display ipv6 multicast-vlan group [ ipv6-source-address | ipv6-group-address | slot slot-number | verbose | vlan vlan-id ] *
Display IPv6 multicast VLAN forwarding entries.	display ipv6 multicast-vlan forwarding-table [ ipv6-source-address [ prefix-length ] | ipv6-group-address [ prefix-length ] | slot slot-number | subvlan vlan-id | vlan vlan-id ] *
Clear IPv6 multicast groups in IPv6 multicast VLANs.	reset ipv6 multicast-vlan group [ ipv6-group-address [ prefix-length ] | ipv6-source-address [ prefix-length ] | vlan vlan-id ] *

 

IPv6 multicast VLAN configuration examples

Sub-VLAN-based IPv6 multicast VLAN configuration example

Network requirements

As shown in Figure 4:

·           MLDv1 runs on Layer 3 device Switch A, and MLDv1 snooping runs on Layer 2 device Switch B.

·           Switch A acts as the MLD querier.

·           The IPv6 multicast source sends IPv6 multicast data to IPv6 multicast group FF1E::101. Host A, Host B, and Host C are receivers. They belong to VLAN 2 through VLAN 4, respectively.

Configure a sub-VLAN-based IPv6 multicast VLAN on Switch B to achieve the following goals:

·           Switch A sends the IPv6 multicast data to Switch B through the IPv6 multicast VLAN.

·           Switch B forwards the IPv6 multicast data to the receivers in different user VLANs.

Figure 4 Network diagram

 

Configuration procedure

1.      Configure Switch A:

# Enable IPv6 multicast routing globally.

<SwitchA> system-view

[SwitchA] ipv6 multicast routing

[SwitchA-mrib6] quit

# Create VLAN 20, and assign Ten-GigabitEthernet 1/0/2 to this VLAN.

[SwitchA] vlan 20

[SwitchA-vlan20] port ten-gigabitethernet 1/0/2

[SwitchA-vlan20] quit

# Assign an IPv6 address to VLAN-interface 20, and enable IPv6 PIM-DM.

[SwitchA] interface vlan-interface 20

[SwitchA-Vlan-interface20] ipv6 address 1::2 64

[SwitchA-Vlan-interface20] ipv6 pim dm

[SwitchA-Vlan-interface20] quit

# Create VLAN 10.

[SwitchA] vlan 10

[SwitchA-vlan10] quit

# Configure Ten-GigabitEthernet 1/0/1 as a hybrid port, and assign it to VLAN 10 as a tagged VLAN member.

[SwitchA] interface ten-gigabitethernet 1/0/1

[SwitchA-Ten-GigabitEthernet1/0/1] port link-type hybrid

[SwitchA-Ten-GigabitEthernet1/0/1] port hybrid vlan 10 tagged

[SwitchA-Ten-GigabitEthernet1/0/1] quit

# Assign an IPv6 address to VLAN-interface 10, and enable MLD on this interface.

[SwitchA] interface vlan-interface 10

[SwitchA-Vlan-interface10] ipv6 address 2001::1 64

[SwitchA-Vlan-interface10] mld enable

[SwitchA-Vlan-interface10] quit

2.      Configure Switch B:

# Enable MLD snooping globally.

<SwitchB> system-view

[SwitchB] mld-snooping

[SwitchB-mld-snooping] quit

# Create VLAN 2, assign Ten-GigabitEthernet 1/0/2 to this VLAN, and enable MLD snooping for this VLAN.

[SwitchB] vlan 2

[SwitchB-vlan2] port ten-gigabitethernet 1/0/2

[SwitchB-vlan2] mld-snooping enable

[SwitchB-vlan2] quit

# Create VLAN 3, assign Ten-GigabitEthernet 1/0/3 to this VLAN, and enable MLD snooping for this VLAN.

[SwitchB] vlan 3

[SwitchB-vlan3] port ten-gigabitethernet 1/0/3

[SwitchB-vlan3] mld-snooping enable

[SwitchB-vlan3] quit

# Create VLAN 4, assign Ten-GigabitEthernet1/0/4 to this VLAN, and enable MLD snooping for this VLAN.

[SwitchB] vlan 4

[SwitchB-vlan4] port ten-gigabitethernet 1/0/4

[SwitchB-vlan4] mld-snooping enable

[SwitchB-vlan4] quit

# Create VLAN 10, and enable MLD snooping for this VLAN.

[SwitchB] vlan 10

[SwitchB-vlan10] mld-snooping enable

[SwitchB-vlan10] quit

# Configure Ten-GigabitEthernet 1/0/1 as a hybrid port, and assign it to VLAN 10 as a tagged VLAN member.

[SwitchB] interface ten-gigabitethernet 1/0/1

[SwitchB-Ten-GigabitEthernet1/0/1] port link-type hybrid

[SwitchB-Ten-GigabitEthernet1/0/1] port hybrid vlan 10 tagged

[SwitchB-Ten-GigabitEthernet1/0/1] quit

# Configure VLAN 10 as an IPv6 multicast VLAN, and configure VLAN 2 through VLAN 4 as sub-VLANs.

[SwitchB] ipv6 multicast-vlan 10

[SwitchB-ipv6-mvlan-10] subvlan 2 to 4

[SwitchB-ipv6-mvlan-10] quit

Verifying the configuration

# Display information about all IPv6 multicast VLANs on Switch B.

[SwitchB] display ipv6 multicast-vlan

Total 1 IPv6 multicast VLANs.

 

IPv6 multicast VLAN 10:

  Sub-VLAN list(3 in total):

     2-4

  Port list(0 in total):

# Display IPv6 multicast VLAN forwarding entries on Switch B.

[SwitchB] display ipv6 multicast-vlan group

Total 1 entries.

 

IPv6 multicast VLAN 10: Total 1 entries.

  (::, FF1E::101)

    Sub-VLANs (3 in total):

      VLAN 2

      VLAN 3

      VLAN 4

The output shows that the IPv6 multicast VLAN (VLAN 10) contains sub-VLANs VLAN 2 through VLAN 4. Switch B will replicate the IPv6 multicast data of VLAN 10 to VLAN 2 through VLAN 4.

Port-based IPv6 multicast VLAN configuration example

Network requirements

As shown in Figure 5:

·           MLDv1 runs on Switch A. MLDv1 snooping runs on Switch B.

·           Switch A acts as the MLD querier.

·           The IPv6 multicast source sends IPv6 multicast data to IPv6 multicast group FF1E::101. Host A, Host B, and Host C are receivers. They belong to VLAN 2 through VLAN 4, respectively.

Configure a port-based IPv6 multicast VLAN on Switch B to achieve the following goals:

·           Switch A sends IPv6 multicast data to Switch B through the IPv6 multicast VLAN.

·           Switch B forwards the IPv6 multicast data to the receivers in different user VLANs.

Figure 5 Network diagram

 

Configuration procedure

1.      Configure Switch A:

# Enable IPv6 multicast routing globally.

<SwitchA> system-view

[SwitchA] ipv6 multicast routing

[SwitchA-mrib6] quit

# Create VLAN 20, and assign Ten-GigabitEthernet 1/0/2 to this VLAN.

[SwitchA] vlan 20

[SwitchA-vlan20] port ten-gigabitethernet 1/0/2

[SwitchA-vlan20] quit

# Assign an IPv6 address to VLAN-interface 20, and enable IPv6 PIM-DM on this interface.

[SwitchA] interface vlan-interface 20

[SwitchA-Vlan-interface20] ipv6 address 1::2 64

[SwitchA-Vlan-interface20] ipv6 pim dm

[SwitchA-Vlan-interface20] quit

# Create VLAN 10, and assign Ten-GigabitEthernet 1/0/1 to the VLAN.

[SwitchA] vlan 10

[SwitchA-vlan10] port ten-gigabitethernet 1/0/1

[SwitchA-vlan10] quit

# Assign an IPv6 address to VLAN-interface 10, and enable MLD on this interface.

[SwitchA] interface vlan-interface 10

[SwitchA-Vlan-interface10] ipv6 address 2001::1 64

[SwitchA-Vlan-interface10] mld enable

[SwitchA-Vlan-interface10] quit

2.      Configure Switch B:

# Enable MLD snooping globally.

<SwitchB> system-view

[SwitchB] mld-snooping

[SwitchB-mld-snooping] quit

# Create VLAN 10, assign Ten-GigabitEthernet 1/0/1 to VLAN 10, and enable MLD snooping for this VLAN.

[SwitchB] vlan 10

[SwitchB-vlan10] port ten-gigabitethernet 1/0/1

[SwitchB-vlan10] mld-snooping enable

[SwitchB-vlan10] quit

# Create VLAN 2, and enable MLD snooping for the VLAN.

[SwitchB] vlan 2

[SwitchB-vlan2] mld-snooping enable

[SwitchB-vlan2] quit

# Create VLAN 3, and enable MLD snooping for the VLAN.

[SwitchB] vlan 3

[SwitchB-vlan3] mld-snooping enable

[SwitchB-vlan3] quit

# Create VLAN 4, and enable MLD snooping for the VLAN.

[SwitchB] vlan 4

[SwitchB-vlan4] mld-snooping enable

[SwitchB-vlan4] quit

# Configure Ten-GigabitEthernet 1/0/2 as a hybrid port, and configure VLAN 2 as the PVID of the hybrid port.

[SwitchB] interface ten-gigabitethernet 1/0/2

[SwitchB-Ten-GigabitEthernet1/0/2] port link-type hybrid

[SwitchB-Ten-GigabitEthernet1/0/2] port hybrid pvid vlan 2

# Assign Ten-GigabitEthernet 1/0/2 to VLAN 2 and VLAN 10 as an untagged VLAN member.

[SwitchB-Ten-GigabitEthernet1/0/2] port hybrid vlan 2 untagged

[SwitchB-Ten-GigabitEthernet1/0/2] port hybrid vlan 10 untagged

[SwitchB-Ten-GigabitEthernet1/0/2] quit

# Configure Ten-GigabitEthernet 1/0/3 as a hybrid port, and configure VLAN 3 as the PVID of the hybrid port.

[SwitchB] interface ten-gigabitethernet 1/0/3

[SwitchB-Ten-GigabitEthernet1/0/3] port link-type hybrid

[SwitchB-Ten-GigabitEthernet1/0/3] port hybrid pvid vlan 3

# Assign Ten-GigabitEthernet 1/0/3 to VLAN 3 and VLAN 10 as an untagged VLAN member.

[SwitchB-Ten-GigabitEthernet1/0/3] port hybrid vlan 3 untagged

[SwitchB-Ten-GigabitEthernet1/0/3] port hybrid vlan 10 untagged

[SwitchB-Ten-GigabitEthernet1/0/3] quit

# Configure Ten-GigabitEthernet 1/0/4 as a hybrid port, and configure VLAN 4 as the PVID of the hybrid port.

[SwitchB] interface ten-gigabitethernet 1/0/4

[SwitchB-Ten-GigabitEthernet1/0/4] port link-type hybrid

[SwitchB-Ten-GigabitEthernet1/0/4] port hybrid pvid vlan 4

# Assign Ten-GigabitEthernet 1/0/4 to VLAN 4 and VLAN 10 as an untagged VLAN member.

[SwitchB-Ten-GigabitEthernet1/0/4] port hybrid vlan 4 untagged

[SwitchB-Ten-GigabitEthernet1/0/4] port hybrid vlan 10 untagged

[SwitchB-Ten-GigabitEthernet1/0/4] quit

# Configure VLAN 10 as an IPv6 multicast VLAN.

[SwitchB] ipv6 multicast-vlan 10

# Assign Ten-GigabitEthernet 1/0/2 and Ten-GigabitEthernet 1/0/3 to VLAN 10.

[SwitchB-ipv6-mvlan-10] port ten-gigabitethernet 1/0/2 to ten-gigabitethernet 1/0/3

[SwitchB-ipv6-mvlan-10] quit

# Assign Ten-GigabitEthernet 1/0/4 to VLAN 10.

[SwitchB] interface ten-gigabitethernet 1/0/4

[SwitchB-Ten-GigabitEthernet1/0/4] ipv6 port multicast-vlan 10

[SwitchB-Ten-GigabitEthernet1/0/4] quit

Verifying the configuration

# Display information about IPv6 multicast VLANs on Switch B.

[SwitchB] display ipv6 multicast-vlan

Total 1 IPv6 multicast VLANs.

 

IPv6 multicast VLAN 10:

  Sub-VLAN list(0 in total):

  Port list(0 in total):

    XGE1/0/2

    XGE1/0/3

    XGE1/0/4

# Display MLD snooping forwarding entries for the dynamic IPv6 multicast groups on Switch B.

[SwitchB] display mld-snooping group

Total 1 entries.

 

VLAN 10: Total 1 entries.

  (::, FF1E::101)

    Host slots (0 in total):

    Host ports (3 in total):

      XGE1/0/2         (00:03:23)

      XGE1/0/3         (00:04:07)

      XGE1/0/4         (00:04:16)

The output shows that MLD snooping maintains the user ports in VLAN 10. Switch B will forward the IPv6 multicast data of VLAN 10 through these user ports.