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This chapter contains the following sections:
To delete the IPv6 multicast Listener Discovery (MLD) group cache entries, use the clear ipv6 mld snooping groups Privileged EXEC mode command.
clear ipv6 mld snooping groups [dynamic | static]
dynamic—(Optional) Deletes dynamic MLD groups.
static—(Optional) Deletes static MLD groups.
Privileged EXEC mode
switchxxxxxx# clear ipv6 mld snooping groupsTo clear the IPv6 MLD snooping statistics, use the clear ipv6 mld snooping statistics Privileged EXEC mode command.
clear ipv6 mld snooping statistics
N/A
Privileged EXEC mode
switchxxxxxx# clear ipv6 mld snooping statisticsTo control whether or not all hosts on a Layer 2 interface can join one or more IPv6 multicast groups by applying a MLD profile to the interface, use the ipv6 mld filter Interface Configuration mode command.
To remove a MLD profile from the interface, use the no form of this command.
ipv6 mld filter profile-number
no ipv6 mld filter
profile-number—The MLD profile number to be applied. (Range: 1 to 128)
No MLD profiles are applied.
Interface Configuration mode
You can apply the MLD profiles only to Layer 2 physical or EtherChannel interfaces.
A MLD profile can be applied to one or more switch interfaces, but one interface can have only one profile applied to it.
switchxxxxxx(config)# interface gi1
switchxxxxxx(config-if)# ipv6 mld filter 22To set the maximum number of MLD groups that an interface can join or to configure the MLD throttling action when the maximum number of entries in the forwarding table is reached, use the ipv6 mld max-groups Interface Configuration mode command.
To set the maximum back to the default setting, which is to have no maximum limit, or to return to the default throttling action, which is to drop the report, use the no form of this command.
ipv6 mld max-groups number
no ipv6 mld max-groups number
ipv6 mld max-groups action {deny | replace}
number—The maximum number of MLD groups that an interface can join.
action deny—When the maximum number of entries in the MLD snooping forwarding table is reached, drops the next MLD join report. This is the default action.
action replace—When the maximum number of entries in the MLD snooping forwarding table is reached, replaces the existing group with the new group for which the MLD report was received.
Interface Configuration mode
You can use this command only on Layer 2 physical interfaces and on logical EtherChannel interfaces.
Follow these guidelines when configuring the MLD throttling action:
If you configure the throttling action as deny and set the maximum group limitation, the entries that were previously in the forwarding table are not removed but are aged out. After these entries are aged out, when the maximum number of entries in the forwarding table is reached, the switch drops the next MLD report received on the interface.
If you configure the throttling action as replace and set the maximum group limitation, the entries that were previously in the forwarding table are removed. When the maximum number of entries in the forwarding table is reached, the switch replaces a randomly selected multicast entry with the received MLD report.
switchxxxxxx(config)# interface gi1
switchxxxxxx(config-if)# ipv6 mld max-groups 25
switchxxxxxx(config-if)# ipv6 mld max-groups action replaceTo create a MLD profile and enter the MLD Profile Configuration mode, use the ipv6 mld profile Global Configuration mode command. From this mode, you can specify the configuration of the IGMP profile to be used for filtering MLD membership reports from a switch port.
To delete a MLD profile, use the no form of this command.
ipv6 mld profile profile-number
no ip igmp profile profile-number
profile-number —The MLD profile number. (Range:1 to 128)
No IGMP profiles are defined.
Global Configuration mode
switchxxxxxx(config)# ipv6 mld profile 20
switchxxxxxx(config-mld-profile)#To enable IPv6 MLD snooping on the switch, use the ipv6 mld snooping Global Configuration mode command.
To disable IPv6 MLD snooping, use the no form of this command.
ipv6 mld snooping [version {1 | 2}]
no ipv6 mld snooping
version 1—(Optional) Specifies the MLD operation version as v1.
version 2—(Optional) Specifies the MLD operation version as v2.
The default MLD version is v1.
Global Configuration mode
switchxxxxxx(config)# ipv6 mld snoopingTo enable IPv6 MLD snooping report suppression on the switch, use the ipv6 mld snooping report-suppression Global Configuration mode command.
To disable this feature, use the no form of this command.
ipv6 mld snooping report-suppression
no ipv6 mld snooping report-suppression
N/A
IPv6 MLD snooping report suppression is disabled by default.
Global Configuration mode
MLD snooping listener message suppression is equivalent to IGMP Snooping report suppression. When enabling MLD snooping report suppression, received MLDv1 reports to a group are forwarded to IPv6 multicast routers only once in every report-forward time. This function prevents the forwarding of duplicate reports.
switchxxxxxx(config)# ipv6 mld snooping report-suppressionTo configure the IPv6 MLD snooping parameters on the VLANs, use the ipv6 mld snooping vlan Global Configuration mode command.
To revert to its default setting, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST
no ipv6 mld snooping vlan VLAN-LIST
VLAN-LIST—A VLAN ID or a range of VLAN IDs. (Range: 1 to 4094)
MLD snooping is disabled on all VLANs.
Global Configuration mode
switchxxxxxx(config)# ipv6 mld snooping vlan 100To enable MLD snooping immediate leave processing on the VLANs, use the ipv6 mld snooping vlan immediate-leave Global Configuration mode command.
To revert to its default setting, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST immediate-leave
no ipv6 mld snooping vlan VLAN-LIST immediate-leave
VLAN-LIST—A VLAN ID or a range of VLAN IDs on which both MLD snooping and immediate leave are enabled.
MLD immediate leave processing is disabled.
Global Configuration mode
You should configure the immediate leave feature only when there is a maximum of one receiver on each interface in the VLAN.
switchxxxxxx(config)# ipv6 mld snooping vlan 3 fastleaveTo forbid a port from being defined as a multicast router port by static configuration or by automatic learning, use the ipv6 mld snooping vlan forbidden mrouter Global Configuration mode command.
To revert to its default settings, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST forbidden mrouter interfaces interface-id
no ipv6 mld snooping vlan VLAN-LIST forbidden mrouter interfaces interface-id
VLAN-LIST—A VLAN ID or a range of VLAN IDs.
interfaces interface-id—Specifies an interface or a list of interface IDs. The interfaces can be one of these types: Ethernet port or port channel.
No ports are defined.
Global Configuration mode
A port that is a forbidden-mrouter-port cannot be a multicast router port (for example, cannot be learned dynamically or assigned statically).
You can execute the command before the VLAN is created.
switchxxxxxx(config)# ipv6 mld snooping vlan 1 forbidden mrouter interfaces gi1To enable the MLD snooping forbidden forward-all processing on the VLANs, use the ipv6 mld snooping vlan forbidden-port Global Configuration mode command.
To disable this feature, use the no form of this command.
ip6 mld snooping vlan VLAN-LIST forbidden forward-all interfaces interface-id
no ip6 mld snooping vlan VLAN-LIST forbidden forward-all interfaces interface-id
VLAN-LIST—A VLAN ID or a range of VLAN IDs.
interfaces interface-id—Specifies an interface ID or a list of interface IDs. The interfaces can be one of these types: Ethernet port or port channel.
No port is configured as a member of a multicast group.
Global Configuration mode
You can execute the command before the VLAN is created.
You can register an entry without specifying an interface.
switchxxxxxx(config)# ipv6 mld snooping vlan 1 forbidden forward-all interfaces fa1
switchxxxxxx(config)# ipv6 mld snooping vlan 1 forbidden forward-all interfaces gi1
switchxxxxxx(config)# ipv6 mld snooping vlan 1 forbidden forward-all interfaces po5To configure IPv6 MLD multicast Address Specific Queries (MASQs) that will be sent before aging out a client, use the ipv6 mld vlan snooping last-member-query-count Global Configuration mode command.
To revert to the default settings, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST last-member-query-count VALUE
no ipv6 mld snooping vlan VLAN-LIST last-member-query-count
VLAN-LIST—A VLAN ID or a range of VLAN IDs.
VALUE—The number of last member queries. (Range: 1 to 7)
The default last member query count is 2.
Global Configuration mode
In MLD snooping, the IPv6 multicast router periodically sends out queries to hosts belonging to the multicast group. If a host wants to leave a multicast group, it can silently leave or it can respond to the query with a multicast Listener Done message (equivalent to an IGMP Leave message). When Immediate Leave is not configured (which it should not be if multiple clients for a group exist on the same port), the configured last-listener query count determines the number of MASQs that are sent before a MLD client is aged out.
switchxxxxxx(config)# ipv6 mld snooping vlan 2 last-member-query-count 5To configure IPv6 MLD snooping last-listener query interval on the switch or on a VLAN, use the ipv6 mld snooping vlan last-member-query-interval Global Configuration mode command. This time interval is the maximum time that a multicast router waits after issuing an MASQ before deleting a port from the multicast group.
To revert to the default settings, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST last-member-query-interval VALUE
no ipv6 mld snooping vlan VLAN-LIST last-member-query-interval
VLAN-LIST—A VLAN ID or a list of VLAN IDs.
VALUE—The MLD query interval in seconds. (Range: 1 to 25)
The default VLAN last member query interval is 1 second.
Global Configuration mode
In MLD snooping, when the IPv6 multicast router receives an MLD leave message, it sends out queries to hosts belonging to the multicast group. If there are no responses from a port to a MASQ for a length of time, the router deletes the port from the membership database of the multicast address. The last listener query interval is the maximum time that the router waits before deleting a non-responsive port from the multicast group. When a VLAN query interval is set, this interval overrides the global query interval. When the VLAN interval is set at 0, the global value is used.
switchxxxxxx(config)# ipv6 mld snooping vlan 3 last-member-query-interval 30To enable automatic learning of multicast router ports on the switch or on a VLAN, use the ipv6 mld snooping vlan mrouter learn pim-dvmrp Global Configuration mode command.
To disable this feature on the VLANs, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST mrouter learn pim-dvmrp
no ipv6 mld snooping vlan VLAN-LIST mrouter learn pim-dvmrp
VLAN-LIST—A VLAN ID or a list of VLAN IDs.
MLD snooping learning pim-dvmrp is enabled.
Global Configuration mode
multicast router ports are learned according to:
Queries received on the port
PIM/PIMv2 received on the port
DVMRP received on the port
MOSPF received on the port
You can execute the command before the VLAN is created.
switchxxxxxx(config)# ipv6 mld snooping vlan 1 mrouter learn pim-dvmrpTo configure IPv6 MLD snooping query interval on the switch or on a VLAN, use the ipv6 mld snooping vlan query-interval Global Configuration mode command. This time interval is the maximum time that a multicast router waits after issuing an MASQ before deleting a port from the multicast group.
To revert to the default settings, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST query-interval VALUE
no ipv6 mld snooping vlan VLAN-LIST query-interval
VLAN-LIST—A VLAN ID or a list of VLAN IDs.
VALUE—The IPv6 MLD snooping query interval. (Range: 30 to 18000)
The default VLAN query interval is 125 seconds.
Global Configuration mode
In MLD snooping, when the IPv6 multicast router receives an MLD leave message, it sends out queries to hosts belonging to the multicast group. If there are no responses from a port to a MASQ for a length of time, the router deletes the port from the membership database of the multicast address. The last listener query interval is the maximum time that the router waits before deleting a non-responsive port from the multicast group.
switchxxxxxx(config)# ipv6 mld snooping vlan 7 query-interval 250To configure the Query Maximum Response time on the VLANs, use the ipv6 mld snooping vlan response-time Global Configuration mode command.
To revert to its default setting, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST response-time seconds
no ipv6 mld snooping vlan VLAN-LIST response-time
VLAN-LIST—A VLAN ID or a list of VLAN IDs.
seconds —Maximum response time, in seconds, advertised in IGMP queries. (Range: 5 to 20)
10
Global Configuration mode
You can execute the command before the VLAN is created.
switchxxxxxx(config)# ipv6 mld snooping vlan 3 response-time 20To configure the number of IPv6 MLD queries that the switch sends before deleting a listener that does not respond, or to enter a VLAN ID to configure on a per-VLAN basis, use the ipv6 mld snooping robustness-variable Global Configuration mode command.
To revert to the default settings, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST robustness-variable VALUE
no ipv6 mld snooping vlan VLAN-LIST robustness-variable
VLAN-LIST—A VLAN ID or a list of VLAN IDs.
VALUE—The range is 1 to 7.
The default VLAN robustness variable is 2.
Global Configuration mode
Robustness is measured in terms of the number of MLDv1 queries sent with no response before a port is removed from a multicast group. A port is deleted when there are no MLDv1 reports received for the configured number of MLDv1 queries. The global value determines the number of queries that the switch waits before deleting a listener that does not respond and applies to all VLANs that do not have a VLAN value set.
switchxxxxxx(config)# ipv6 mld snooping vlan 7 robustness-variable 5To enable the MLD snooping static group processing on a VLAN, use the ipv6 mld snooping vlan static interface Global Configuration mode command.
To disable this feature on the VLAN, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST static IPv6-Addr interface interface-id
no ipv6 mld snooping vlan VLAN-LIST static IPv6-Addr interface interface-id
VLAN-LIST—A VLAN ID or a list of VLAN IDs.
IPv6-Addr—The IPv6 multicast address.
interface-id—The interface ID, which can be one of these types: Ethernet port or port channel.
No ports are configured as a member of a multicast group.
Global configuration mode
You can execute the command before the VLAN is created.
Using the no command without a port list removes the entry.
switchxxxxxx(config)# ipv6 mld snooping vlan 1 static abcd::1234 interface fa1
switchxxxxxx(config)# ipv6 mld snooping vlan 1 static abcd::1234 interface gi1
switchxxxxxx(config)# ipv6 mld snooping vlan 1 static abcd::1234 interface po3To register a Layer 2 port as a member of a static multicast group to the bridge table, use the ipv6 mld snooping vlan mrouter Global Configuration mode command.
To remove the ports specified as members from a static Mrouter port, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST mrouter interfaces interface-id
no ipv6 mld snooping vlan VLAN-LIST mrouter interfaces interface-id
VLAN-LIST—A VLAN ID or a list of VLAN IDs.
interfaces interface-id—Specifies an interface ID or a list of interface IDs. The interfaces can be one of these types: Ethernet port or port channel.
No port is configured as a member of a static Mrouter port.
Global Configuration mode
You can execute the command before the VLAN is created.
You can register an entry without specifying an interface.
Using the no command without a port list removes the entry.
switchxxxxxx(config)# ipv6 mld snooping vlan 1 mrouter interfaces fa1
switchxxxxxx(config)# ipv6 mld snooping vlan 1 mrouter interfaces gi1
switchxxxxxx(config)# ipv6 mld snooping vlan 1 mrouter interfaces po3To enable the MLD snooping forward-all static port processing on a VLAN, use the ipv6 mld snooping vlan forward-all Global Configuration mode command.
To disable this feature on the VLAN, use the no form of this command.
ipv6 mld snooping vlan VLAN-LIST forward-all interfaces interface-id
no ipv6 mld snooping vlan VLAN-LIST forward-all interfaces interface-id
VLAN-LIST—A VLAN ID or a list of VLAN IDs.
interfaces interface-id—Specifies an interface ID or a list of interface IDs. The interfaces can be one of these types: Ethernet port or port channel.
No port is configured as a member of a multicast group.
Global Configuration mode
You can execute the command before the VLAN is created.
You can register an entry without specifying an interface.
Using the no command without a port list removes the entry.
switchxxxxxx(config)# ipv6 mld snooping vlan 1 forward-all interfaces fa1
switchxxxxxx(config)# ipv6 mld snooping vlan 1 forward-all interfaces gi1
switchxxxxxx(config)# ipv6 mld snooping vlan 1 forward-all interfaces po1To create a MLD profile for a range of IPv6 addresses, use the profile range MLD-profile Configuration mode command.
To remove a MLD profile for a range of IPv6 addresses, use the no form of this command.
profile range ipv6 ipv6-range action {deny | permit}
ipv6 ipv6-range—Specifies a range of IPv6 addresses for the profile. This can be a single IPv6 address or a range with a start and an end address. When entering a range, enter the low IPv6 multicast address, a space, and the high IPv6 multicast address.
action deny—Denies the matching addresses.
action permit—Permits the matching addresses.
N/A
MLD-profile Configuration mode
switchxxxxxx(config)# ip igmp profile 1
switchxxxxxx(config-mld-profile)# profile range ipv6 ff07::1:3 ff07::1:ff action permitTo display the IPv6 MLD profiles for all interfaces or for a specific interface, use the show ipv6 mld filter Privileged EXEC mode command.
show ipv6 mld filter [interfaces interface-id]
interfaces interface-id —(Optional) Specifies an interface ID or a list of interface IDs.
Privileged EXEC mode
switchxxxxxx# show ipv6 mld filter
Port ID | Profile ID
---------+--------------
fa1 : None
fa2 : 1
fa3 : 1
fa4 : 2
fa5 : None
fa6 : None
fa7 : None
fa8 : None
fa9 : None
fa10 : None
fa11 : None
fa12 : None
fa13 : None
fa14 : None
fa15 : None
fa16 : None
fa17 : None
fa18 : None
fa19 : None
fa20 : None
fa21 : None
fa22 : None
fa23 : None
fa24 : None
gi1 : None
gi2 : None
po1 : None
po2 : None
po3 : None
po4 : None
po5 : None
po6 : None
po7 : None
po8 : NoneTo display the maximum number of IPv6 MLD groups on a specific interface or all interfaces, use the show ipv6 mld max-group Privileged EXEC mode command.
show ipv6 mld max-group [interfaces interface-id]
interfaces interface-id—(Optional) Specifies an interface ID or a list of interface IDs. The interfaces can be one of these types: Ethernet port or port channel.
Privileged EXEC mode
If no interface is specified, the information for all interfaces is displayed.
switchxxxxxx# show ipv6 mld max-group interfaces fa5
Port ID | Max Group
---------+--------------
fa5 : 512To display the action for a specific interface or for all interfaces when the number of IPv6 MLD groups exceeds the maximum group number, use the show ipv6 mld max-group action Privileged EXEC mode command.
show ipv6 mld max-group action [interfaces interface-id]
interfaces interface-id—(Optional) Specifies an interface ID or a list of interface IDs. The interfaces can be one of these types: Ethernet port or port channel.
Privileged EXEC mode
If no interface is specified, the information for all interfaces is displayed.
switchxxxxxx# show ipv6 mld max-group action interfaces fa5
Port ID | Max-groups Action
---------+---------------------
fa5 : denyTo display the IPv6 MLD profile information, use the show ipv6 mld profile Privileged EXEC mode command.
show ipv6 mld profile [profile-index]
profile-index—(Optional) The MLD profile index.
Privileged EXEC mode
switchxxxxxx# show ipv6 mld profile
IPv6 mld profile index: 1
IPv6 mld profile action: deny
Range low ip: ff51::
Range high ip: ff52::To display the MLD snooping configuration, use the show ipv6 mld snooping Privileged EXEC mode command.
show ipv6 mld snooping
N/A
Privileged EXEC mode
switchxxxxxx# show ipv6 mld snooping
MLD Snooping Status
--------------------
Snooping : Disabled
Report Suppression : Enabled
Operation Version : v1
Forward Method : mac
Unknown Multicast Action : Flood
Packet Statistics
Total RX : 0
Valid RX : 0
Invalid RX : 0
Other RX : 0
Leave RX : 0
Report RX : 0
General Query RX : 0
Special Group Query RX : 0
Special Group & Source Query RX : 0
Leave TX : 0
Report TX : 0
General Query TX : 0
Special Group Query TX : 0
Special Group & Source Query TX : 0To display information for IPv6 MLD snooping forward all, use the show ipv6 mld snooping forward-all Privileged EXEC mode command.
show ipv6 mld snooping forward-all [vlan VLAN_LIST]
vlan VLAN-LIST—(Optional) Specifies a VLAN ID or a list of VLAN IDs.
Privileged EXEC mode
switchxxxxxx# show ipv6 mld snooping forward-all
MLD Snooping VLAN : 1
MLD Snooping static port : None
MLD Snooping forbidden port : None
MLD Snooping VLAN : 2
MLD Snooping static port : None
MLD Snooping forbidden port : None
MLD Snooping VLAN : 3
MLD Snooping static port : None
MLD Snooping forbidden port : None
MLD Snooping VLAN : 4
MLD Snooping static port : None
MLD Snooping forbidden port : None
MLD Snooping VLAN : 5
MLD Snooping static port : None
MLD Snooping forbidden port : None
MLD Snooping VLAN : 6
MLD Snooping static port : None
MLD Snooping forbidden port : None
MLD Snooping VLAN : 7
MLD Snooping static port : None
MLD Snooping forbidden port : None
MLD Snooping VLAN : 8
MLD Snooping static port : None
MLD Snooping forbidden port : None
MLD Snooping VLAN : 9
MLD Snooping static port : None
MLD Snooping forbidden port : None
MLD Snooping VLAN : 10
MLD Snooping static port : None
MLD Snooping forbidden port : NoneTo display multicast groups learned by MLD snooping, use the show ipv6 mld snooping groups Privileged EXEC mode command.
show ipv6 mld snooping groups [{dynamic | static} | counters]
dynamic—(Optional) Displays the dynamic groups.
static—(Optional) Displays the static groups.
counters—(Optional) IPv6 MLD snooping group counters.
Privileged EXEC mode
To display information for all multicast groups learned by MLD snooping, use the show ipv6 mld snooping groups command without parameters.
To display information for a subset of all multicast groups learned by MLD snooping, use the show ipv6 mld snooping groups command with parameters.
switchxxxxxx# show ipv6 mld snooping groups
VLAN | Group IP Address | Type | Life(Sec) | Port
------+------------------+--------+-----------+------------------
Total Number of Entry = 0To display information for dynamically, static, or forbidden learned multicast router port for all VLANs or for a specific VLAN, use show ipv6 mld snooping mrouter Privileged EXEC mode command.
show ipv6 mld snooping mrouter [dynamic | static | forbidden]
dynamic—(Optional) Displays the dynamic groups.
forbidden—(Optional) Displays the forbidden routers.
static—(Optional) Displays the static groups.
Privileged EXEC mode
switchxxxxxx# show ipv6 mld snooping mrouter
Dynamic Mrouter Table
VID | Port | Expiry Time(Sec)
------+---------+------------------
Total Entry 0
Static Mrouter Table
VID | Port Mask
------+------------------------
Total Entry 0
Forbidden Mrouter Table
VID | Port Mask
------+------------------------
Total Entry 0To display the MLD snooping configuration on specific VLANs, use the show ipv6 mld snooping vlan Privileged EXEC mode command.
show ipv6 mld snooping vlan [VLAN-LIST]
VLAN-LIST —(Optional) A VLAN ID or a list of VLAN IDs.
Privileged EXEC mode
switchxxxxxx# show ipv6 mld snooping vlan 100
MLD Snooping is globally enabled
MLD Snooping VLAN 1 admin : disabled
MLD Snooping oper mode : disabled
MLD Snooping robustness: admin 2 oper 2
MLD Snooping query interval: admin 125 sec oper 125 sec
MLD Snooping query max response : admin 10 sec oper 10 sec
MLD Snooping last member query counter: admin 2 oper 2
MLD Snooping last member query interval: admin 1000 sec oper 1000 sec
MLD Snooping last immediate leave: disabled
MLD Snooping automatic learning of mrouter ports: enabled
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