Table Of Contents
beacon (multicast routing monitor)
class-map type multicast-flows
clear ip igmp snooping filter statistics
clear ip igmp snooping statistics
clear ip multicast redundancy statistics
clear ip pim snooping statistics
clear ip rtp header-compression
clear mls ip multicast bidir-rpcache
clear mls ip multicast statistics
clear router-guard ip multicast statistics
ip dvmrp routehog-notification
IP Multicast Commands
beacon (multicast routing monitor)
To change the frequency, duration, or scope of beacon messages that the Manager sends to Test Senders and Test Receivers during a Multicast Routing Monitor (MRM) test, use the beacon command in MRM manager configuration mode. To restore the default settings, use the no form of this command.
beacon [interval seconds] [holdtime seconds] [ttl ttl-value]
no beacon [interval seconds] [holdtime seconds] [ttl ttl-value]
Syntax Description
Command Default
Beacon messages are sent at an interval of 60 seconds. The duration of a test period is 86400 seconds (1 day). The TTL for beacon messages is 32 hops.
Command Modes
MRM manager configuration (config-mrm-manager)
Command History
Usage Guidelines
The beacon message functions like a keepalive message. The Manager multicasts beacon messages to the Test Sender and Test Receiver. Beacon messages include the sender requests and receiver requests to start the test, thus providing redundancy in case the Test Sender or Test Receiver goes down.
Examples
The following example shows how to customize the Manager to send beacon messages every 30 minutes (1800 seconds), for a test period of 12 hours (43,200 seconds), with a TTL of 40 hops:
ip mrm manager testbeacon interval 1800 holdtime 43200 ttl 40Related Commands
manager
Specifies that an interface is the Manager for MRM, and specifies the multicast group address the Test Receiver will listen to.
class-map type multicast-flows
To enter multicast-flows class-map configuration mode to create or modify an Internet Group Management Protocol (IGMP) static group class map, use the class-map type multicast-flows command in global configuration mode. To delete an IGMP static group range class map, use the no form of this command.
class-map type multicast-flows class-map-name
no class-map type multicast-flows class-map-name
Syntax Description
Command Default
No IGMP static group class maps are configured.
Command Modes
Global configuration (config)
Command History
Usage Guidelines
Use the class-map type multicast-flows command to enter multicast-flows class-map configuration mode to create or modify IGMP static group class maps.
Unlike quality of service (QoS) class maps, which you define by specifying numerous match criteria, you define IGMP static group class maps by specifying multicast groups entries (group addresses, group ranges, Source Specific Multicast [SSM] channels, and SSM channel ranges). The group command is used to define the group entries to be associated with a class map.
After using the class-map type multicast-flows command to specify the name of the IGMP static group class map to be created or modified, use the following forms of the group command in multicast-flows class-map configuration mode to define the group entries to be associated with the class map:
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group group-address
Defines a group address to be associated with an IGMP static group class map.
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Defines a range of group addresses to be associated with an IGMP static group class map.
•
Defines an SSM channel to be associated with an IGMP static group class map.
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Defines a range of SSM channels to be associated with an IGMP static group class map.
Unlike QoS class maps, IGMP static group range class maps are not configured in traffic policies. Rather, the ip igmp static-group command has been extended to support IGMP static group ranges. After creating an IGMP static group class map, you can attach the class map to interfaces using the ip igmp static-group command with the class-map keyword and class-map-name argument. Once a class map is attached to an interface, all group entries defined in the class map become statically connected members on the interface and are added to the IGMP cache and IP multicast route (mroute) table.
Additional Guidelines for Configuring IGMP Static Group Class Maps
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Use the show ip igmp static-group class-map command to display the contents of IGMP static group class map configurations and information about the interfaces using class maps.
Examples
The following example shows how to create a class map named static1 and enter multicast-flows class-map configuration mode:
class-map type multicast-flows static1The following example shows how to define a range of SSM channels to be associated with an IGMP static group class map:
group 192.0.2.0 source 192.0.2.10Related Commands
clear ip cgmp
To clear all group entries from the caches of Catalyst switches, use the clear ip cgmp command in privileged EXEC mode.
clear ip cgmp [interface-type interface-number]
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
This command sends a Cisco Group Management Protocol (CGMP) leave message with a group address of 0000.0000.0000 and a unicast address of 0000.0000.0000. This message instructs the switches to clear all group entries they have cached.
If an interface type and number are specified, the leave message is sent only on that interface. Otherwise, it is sent on all CGMP-enabled interfaces.
Examples
The following example clears the CGMP cache:
Router# clear ip cgmpRelated Commands
ip cgmp
Enables CGMP on an interface of a router connected to a Catalyst 5000 switch.
clear ip dvmrp route
Note
To delete routes from the Distance Vector Multicast Routing Protocol (DVMRP) routing table, use the clear ip dvmrp route command in privileged EXEC mode.
clear ip dvmrp route {* | route}
Syntax Description
*
Clears all routes from the DVMRP table.
route
Name of the longest matched route to be cleared. Can be an IP address, a network number, or an IP Domain Name System (DNS) name.
Command Modes
Privileged EXEC
Command History
Examples
The following example shows how to delete route 10.1.1.1 from the DVMRP routing table:
Router# clear ip dvmrp route 10.1.1.1clear ip igmp group
To delete entries from the Internet Group Management Protocol (IGMP) cache, use the clear ip igmp group command in privileged EXEC mode.
clear ip igmp [vrf vrf-name] group [group-name group-address | interface-type interface-number]
Cisco 7600 Series
clear ip igmp [vrf vrf-name] group [interface interface-number | group-name | group-address] [loopback interface-number | null interface-number | port-channel number | vlan vlan-id]
Defaults
Defaults
When this command is entered with no keywords or arguments, all entries are deleted from the IGMP cache.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The IGMP cache contains a list of the multicast groups of which hosts on the directly connected LAN are members. If the router has joined a group, that group is also listed in the cache.
To delete all entries from the IGMP cache, specify the clear ip igmp group command with no arguments.
The interface-number argument designates the module and port number. Valid values for interface-number depend on the specified interface type and the chassis and module that are used. For example, if you specify a Gigabit Ethernet interface and have a 48-port 10/100BASE-T Ethernet module that is installed in a 13-slot chassis, valid values for the module number are from 1 to 13 and valid values for the port number are from 1 to 48.
Examples
The following example shows how to clear entries for the multicast group 224.0.255.1 from the IGMP cache:
Router# clear ip igmp group 224.0.255.1Cisco 7600 Series
This example shows how to clear the IGMP-group cache entries from a specific interface of the IGMP-group cache:
Router# clear ip igmp group gigabitethernet 2/2Router#Related Commands
clear ip igmp snooping filter statistics
To clear Internet Group Management Protocol (IGMP) filtering statistics, use the clear ip igmp snooping filter statistics command in privileged EXEC mode.
clear ip igmp snooping filter statistics interface type mod/port [vlan vlan-id]
Syntax Description
Command Default
This command has no default settings.
Command Modes
Privileged EXEC (#)
Command History
Examples
This example shows how to clear statistics for all access ports and for all VLANs on all trunk ports:
Router# clear ip igmp snooping filter statisticsThis example shows how to clear statistics for one particular access port or for all VLANs on one particular trunk port:
Router# clear ip igmp snooping filter statistics interface gigabitethernet 3/2This example shows how to clear statistics for one particular VLAN on a trunk port:
Router# clear ip igmp snooping filter statistics interface gigabitethernet 3/2 vlan 100Related Commands
clear ip igmp snooping statistics
To clear the IGMP-snooping statistics, use the clear ip igmp snooping statistics command in privileged EXEC mode.
clear ip igmp snooping statistics [vlan vlan-id]
Syntax Description
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
If you do not enter a VLAN, the IGMP-snooping statistics for all VLANs is cleared.
Examples
This example shows how to clear the IGMP-snooping statistics for all VLANs:
Router# clear ip igmp snooping statisticsThis example shows how to clear the IGMP-snooping statistics for a specific VLAN:
Router# clear ip igmp snooping statistics vlan 300Related Commands
clear ip mfib counters
To reset all active IPv4 Multicast Forwarding Information Base (MFIB) traffic counters, use the clear ip mfib counters command in privileged EXEC mode.
clear ip mfib [vrf {vrf-name | *}] counters [group-address/mask | group-address [source-address] | source-address group-address]
Syntax Description
Command Default
When this command is entered with no optional keywords or arguments, all active IPv4 MFIB traffic counters for all multicast tables are reset.
Command Modes
Privileged EXEC (#)
Command History
Usage Guidelines
Use the clear ip mfib counters command to reset all active IPv4 MFIB traffic counters.
This command will reset the active IPv4 MFIB traffic counters displayed in the output of the following commands:
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Examples
The following example shows how to reset all active MFIB traffic counters for all multicast tables:
Router# clear ip mfib countersRelated Commands
clear ip mrm status-report
To clear the Multicast Routing Monitor (MRM) status report cache, use the clear ip mrm status-report command in privileged EXEC mode.
clear ip mrm status-report [ip-address]
Syntax Description
ip-address
(Optional) IP address of the Test Receiver for which to clear status reports from the MRM status report cache.
Command Default
If no IP address is specified for the optional ip-address argument, all status reports are cleared from the MRM status report cache.
Command Modes
Privileged EXEC (#)
Command History
Usage Guidelines
Use the clear ip mrm status-report command to clear the MRM status report cache.
Use the clear ip mrm status-report command with the ip-address argument to clear only the status reports sent by the Test Receiver at the specified IP address. If no IP address is specified for the optional ip-address argument, all status reports are cleared from the MRM status report cache.
Use the show ip mrm status-report to display the status reports in the MRM status report cache.
Examples
The following example shows how to clear status reports sent by a specific Test Receiver from the MRM status report cache. In this example, the status reports sent by the Test Receiver at 172.16.0.0 are cleared from the MRM status report cache.
Router# clear ip mrm status-report 172.16.0.0Related Commands
show ip mrm status-report
Displays the status reports in the MRM status report cache.
clear ip mroute
To delete entries from the IP multicast routing table, use the clear ip mroute command in privileged EXEC mode.
clear ip mroute [vrf vrf-name] {* | group} [source]
Syntax Description
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The group argument specifies one of the following:
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If you specify a group name or address, you can also enter the source argument to specify a name or address of a multicast source that is sending to the group. A source does not need to be a member of the group.
Examples
The following example shows how to delete all entries from the IP multicast routing table:
Router# clear ip mroute *The following example shows how to delete all sources on the 228.3.0.0 subnet that are sending to the multicast group 224.2.205.42 from the IP multicast routing table. This example shows how to delete all sources on network 228.3, not individual sources.
Router# clear ip mroute 224.2.205.42 228.3.0.0Related Commands
clear ip msdp peer
To clear the TCP connection to the specified Multicast Source Discovery Protocol (MSDP) peer, use the clear ip msdp peer command in privileged EXEC mode.
clear ip msdp [vrf vrf-name] peer {peer-address | peer-name}
Syntax Description
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
This command closes the TCP connection to the peer, resets all the MSDP peer statistics, and clears the input and output queues to and from the MSDP peer.
Examples
The following example shows how to clear the TCP connection to the MSDP peer at 10.3.32.154:
Router# clear ip msdp peer 10.3.32.154Related Commands
clear ip msdp sa-cache
To clear Multicast Source Discovery Protocol (MSDP) Source-Active (SA) cache entries, use the clear ip msdp sa-cache command in privileged EXEC mode.
clear ip msdp [vrf vrf-name] sa-cache [group-address | group-name]
Syntax Description
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
In order to have any SA entries in the cache to clear, SA caching must have been enabled with the ip msdp cache-sa-state command.
If no multicast group is identified by group address or name, all SA cache entries are cleared.
Examples
The following example shows how to clear the SA entries for the multicast group 10.3.50.152 from the cache:
Router# clear ip msdp sa-cache 10.3.50.152Related Commands
ip host
Configures an MSDP peer.
ip msdp cache-sa-state
Enables the router to create SA state.
show ip msdp sa-cache
Displays (S, G) state learned from MSDP peers.
clear ip msdp statistics
To clear statistics counters for one or all of the Multicast Source Discovery Protocol (MSDP) peers without resetting the sessions, use the clear ip msdp statistics command in privileged EXEC mode.
clear ip msdp [vrf vrf-name] statistics [peer-address | peer-name]
Syntax Description
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Examples
The following example shows how to clear the counters for the peer named peer1:
Router# clear ip msdp statistics peer1Related Commands
clear ip multicast limit
To reset the exceeded counter for per interface mroute state limiters, use the clear ip multicast limit command in privileged EXEC mode.
clear ip multicast limit [type number]
Syntax Description
type number
(Optional) Interface type and number for which to reset the exceeded counter for per interface mroute state limiters.
Command Default
The exceeded counter for all per interface mroute state limiters are reset.
Command Modes
Privileged EXEC (#)
Command History
Usage Guidelines
Use the clear ip multicast limit command to reset the exceeded counter for per interface mroute state limiters (configured with the ip multicast limit command) that are displayed in the output of the show ip multicast limit command. The exceeded counter tracks the total number of times that the limit configured for the per interface mroute state limiter has been exceeded. Each time an mroute is denied due to the configured limit being reached, the exceeded counter is increased by a value of 1.
Specifying an interface for the optional type and number resets the exceeded counter for only per interface mroute state limiters configured on the specified interface. When no interface is specified for the optional type and number argument, the clear ip multicast limit command resets the exceeded counters globally (for all per interface mroute state limiters configured on the router).
Examples
The following example shows how to reset exceeded counters for mroute state limiters configured on Gigabit Ethernet interface 1/0:
clear ip multicast limit GigabitEthernet1/0Related Commands
clear ip multicast redundancy statistics
To clear IP multicast redundancy statistics, use the clear ip multicast redundancy statistics command in privileged EXEC mode.
clear ip multicast redundancy statistics
Syntax Description
This command has no arguments or keywords.
Command Modes
Privileged EXEC (#)
Command History
Examples
The following example shows how to clear IP multicast redundancy statistics:
Router# clear ip multicast redundancy statisticsRelated Commands
show ip multicast redundancy statistics
Displays IP multicast redundancy statistics.
clear ip pgm host
Note
To reset Pragmatic General Multicast (PGM) Host connections to their default values and to clear traffic statistics, use the clear ip pgm host command in privileged EXEC mode.
clear ip pgm host {defaults | traffic}
Syntax Description
defaults
Resets all PGM Host connections to their default values.
traffic
Clears all PGM Host traffic statistics.
Defaults
No default behavior or values
Command Modes
Privileged EXEC
Command History
Usage Guidelines
This command should be used only in rare cases or during debugging. A reason to reset all PGM Host connections to their default values is to eliminate configuration errors in one step. A reason to clear traffic statistics is to make diagnostic testing easier.
Examples
The following example resets all PGM Host connections to their default values:
Router# clear ip pgm host defaultsThe following example clears all PGM Host traffic statistics:
Router# clear ip pgm host trafficRelated Commands
ip pgm host
Enables PGM Host.
show ip pgm host defaults
Displays default values for PGM Host traffic.
show ip pgm host traffic
Displays PGM Host traffic statistics.
clear ip pgm router
To clear Pragmatic General Multicast (PGM) traffic statistics, use the clear ip pgm router command in privileged EXEC mode.
clear ip pgm router [traffic [interface-type interface-number] | rtx-state [group-address]]
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
This command should be used only in rare cases or during debugging. Normally, the resend state memory is freed automatically when the information is no longer useful. Also, using this command briefly affects the normal PGM behavior.
A reason to clear traffic statistics is to make diagnostic testing easier.
A reason to clear state might be to free the memory consumed by such state. PGM resend state times out if no traffic keeps it alive.
Examples
The following example clears all PGM resend state from the router:
Router# clear ip pgm router rtx-stateRelated Commands
clear ip pim auto-rp
The clear ip pim auto-rp command is replaced by the clear ip pim rp-mapping command. See the clear ip pim rp-mapping command for more information.
clear ip pim interface count
To clear all line card counts or packet counts, use the clear ip pim interface count command in user EXEC or privileged EXEC mode.
clear ip pim interface count
Syntax Description
This command has no arguments or keywords.
Command Modes
User EXEC
Privileged EXECCommand History
Usage Guidelines
Use this command on a Router Processor (RP) to delete all multicast distributed switching (MDS) statistics for the entire router.
Examples
The following example shows how to clear all the line card packets counts:
Router# clear ip pim interface countRelated Commands
clear ip mds forwarding
Clears all routes from the MFIB table of a line card and resynchronizes it with the RP.
clear ip pim rp-mapping
To delete group-to-rendezvous point (RP) mapping entries from the RP mapping cache, use the clear ip pim rp-mapping command in privileged EXEC mode.
clear ip pim [vrf vrf-name] rp-mapping [ ip-address]
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The clear ip pim rp-mapping command replaces the clear ip pim auto-rp command.
The clear ip pim rp-mapping command deletes group-to-RP mapping entries learned by Auto-RP or by a bootstrap router (BSR) from the RP mapping cache.
Use the show ip pim rp command to display active RPs that are cached with associated multicast routing entries.
Examples
The following example shows how to clear all group-to-RP entries from the RP mapping cache:
Router# clear ip pim rp-mappingRelated Commands
show ip pim rp
Displays active RPs that are cached with associated multicast routing entries.
clear ip pim snooping statistics
To delete the IP PIM-snooping global statistics, use the clear ip pim snooping statistics command in privileged EXEC mode.
clear ip pim snooping statistics
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear the IP PIM statistics:
Router# clear ip pim snooping statisticsRelated Commands
ip pim snooping (global configuration mode)
Enables PIM snooping globally.
show ip pim snooping statistics
Displays statistical information about IP PIM snooping.
clear ip pim snooping vlan
To delete the IP PIM-snooping entries on a specific VLAN, use the clear ip pim snooping vlan command in privileged EXEC mode.
clear ip pim snooping vlan vlan-id mac-address gda-address
clear ip pim snooping vlan vlan-id mroute {* | {group-addr src-addr} {{downstream-neighbor} ip-addr} | {upstream-neighbor ip-addr}}}
clear ip pim snooping vlan vlan-id neighbor {* | ip-addr}
Syntax Description
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear the IP PIM-snooping entries on a specific VLAN:
Router# clear ip pim snooping vlan 25Related Commands
ip pim snooping (interface configuration mode)
Enables PIM snooping on a specific interface.
show ip pim snooping
Displays information about IP PIM snooping.
clear ip rtp header-compression
To clear Real-Time Transport Protocol (RTP) header compression structures and statistics, use the clear ip rtp header-compression command in privileged EXEC mode.
clear ip rtp header-compression [interface-type interface-number]
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
If this command is used without an interface type and number, it clears all RTP header compression structures and statistics.
Examples
The following example clears RTP header compression structures and statistics for serial interface 0:
Router# clear ip rtp header-compression serial 0Related Commands
clear ip sap
To delete a Session Announcement Protocol (SAP) cache entry or the entire SAP cache, use the clear ip sap command in privileged EXEC mode.
clear ip sap [group-address | "session-name"]
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
If no arguments or keywords are used with this command, the system deletes the entire SAP cache.
Examples
The following example clears the SAP cache:
Router# clear ip sap "Sample Session"Related Commands
clear ip sdr
The clear ip sdr command is replaced by the clear ip sap command. See the description of the clear ip sap command in this chapter for more information.
clear mls ip multicast bidir-rpcache
To clear all Bidir rendezvous-point cache entries, use the clear mls ip multicast bidir-rpcache command in privileged EXEC mode.
clear mls ip multicast bidir-rpcache
Syntax Description
This command has no keywords or arguments.
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to reset the Bidir counters:
Router# clear mls ip multicast bidir-rpcacheRelated Commands
clear mls ip multicast group
To delete an IP multicast group, use the clear mls ip multicast group command in privileged EXEC mode.
clear mls ip multicast group {ip-name | group-address}
Syntax Description
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to delete an IP multicast group:
Router# clear mls ip multicast group 224.0.255.1Related Commands
show mls ip multicast group
Displays the entries for a specific multicast-group address.
clear mls ip multicast statistics
To reset the IP-multicast statistics counters, use the clear mls ip multicast statistics command in privileged EXEC mode.
clear mls ip multicast statistics
Syntax Description
This command has no keywords or arguments.
Defaults
This command has no default settings.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to reset the IP-multicast statistics counters:
Router# clear mls ip multicast statisticsRelated Commands
clear router-guard ip multicast statistics
To clear router guard statistics, use the clear router-guard ip multicast statistics command in privileged EXEC mode.
clear router-guard ip multicast statistics [interface type mod/port [vlan vlan-id]]
Syntax Description
Command Default
This command has no default settings.
Command Modes
Privileged EXEC (#)
Command History
Examples
This example shows how to clear router guard statistics for all access ports and for all VLANs on all trunk ports:
Router# clear router-guard ip multicast statisticsThis example shows how to clear router guard statistics for one particular access port or for all VLANs on one particular trunk port:
Router# clear router-guard ip multicast statistics interface gigabitethernet 3/2This example shows how to clear router guard statistics for one particular VLAN on a trunk port:
Router# clear router-guard ip multicast statistics interface gigabitethernet 3/2 vlan 100Related Commands
group (multicast-flows)
To define the group entries to be associated with an Internet Group Management Protocol (IGMP) static group class map, use the group command in class-map multicast-flows configuration mode. To delete an entry from an IGMP static group class map, use the no form of this command.
group group-address [to group-address] [source source-address]
no group group-address [to group-address] [source source-address]
Syntax Description
Command Default
No group entries are defined in IGMP static group class maps.
Command Modes
Class-map multicast-flows configuration (config-mcast-flows-cmap)
Command History
Usage Guidelines
Use the group command to define group entries to be associated with an IGMP static group class map. You can use this command only after entering the class-map type multicast-flows command to enter multicast-flows class-map configuration mode to create or modify an IGMP static group class map.
Once you enter multicast-flows class-map configuration mode, use the following forms of the group command to define the group entries to be associated with an IGMP static group class map:
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Defines a group address to be associated with an IGMP static group class map.
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Defines a range of group addresses to be associated with an IGMP static group class map.
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Defines an SSM channel to be associated with an IGMP static group class map.
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Defines a range of SSM channels to be associated with an IGMP static group class map.
After creating an IGMP static group class map, you can attach the class map to interfaces using the ip igmp static-group command with the class-map keyword and class-map-name argument. Once a class map is attached to an interface, all group entries defined in the class map become statically connected members on the interface and are added to the IGMP cache and IP multicast route (mroute) table.
Examples
The following example shows how to define a range of group addresses to be associated with an IGMP static group class map named test:
class-map type multicast-flows testgroup 227.7.7.7 to 227.7.7.9Related Commands
ip cgmp
To enable Cisco Group Management Protocol (CGMP) on an interface of a router connected to a Cisco Catalyst switch, use the ip cgmp command in interface configuration mode. To disable CGMP routing, use the no form of this command.
ip cgmp [proxy | router-only]
no ip cgmp
Syntax Description
proxy
(Optional) Enables CGMP and the CGMP proxy function.
router-only
(Optional) Enables the router to send only CGMP self-join and CGMP self-leave messages.
Defaults
CGMP is disabled.
Command Modes
Interface configuration
Command History
Usage Guidelines
When enabled on an interface, this command triggers a CGMP join message. This command should be used only on 802 media (that is, Ethernet, FDDI, or Token Ring) or ATM. When a no ip cgmp command is issued, a triggered CGMP leave message is sent for the MAC address on the interface for group 0000.0000.0000 (all groups). CGMP can run on an interface only if Protocol Independent Multicast (PIM) is configured on the same interface.
A Cisco router will send CGMP join messages in response to receiving Internet Group Management Protocol (IGMP) reports from IGMP-capable members. Only the CGMP querier Cisco router sends these CGMP join messages on behalf of hosts.
The ip cgmp router-only command enables the routers in a VLAN to send only CGMP self-join and CGMP self-leave messages—no other types of CGMP messages will be sent. This feature allows other CGMP-capable routers to learn about multicast router ports. If the ip cgmp router-only command is not available on any of the external routers in the network, the ip cgmp command can be used instead. Issuing the ip cgmp command on a router enables that router to send CGMP self-join and CGMP self-leave messages as well as other types of CGMP messages.
When the proxy keyword is specified, the CGMP proxy function is also enabled. That is, any router that is not CGMP-capable will be advertised by the proxy router. The proxy router advertises the existence of other non-CGMP-capable routers by sending a CGMP join message with the MAC address of the non-CGMP-capable router and a group address of 0000.0000.0000.
Initially supported is Distance Vector Multicast Routing Protocol (DVMRP) proxying. If a DVMRP report is received from a router that is not a PIM router, a Cisco IGMP querier will advertise the MAC address of the DVMRP router in a CGMP join message with the group address 0000.0000.0000.
To perform CGMP proxy, a Cisco router must be the IGMP querier. If you configure the ip cgmp proxy command, you must manipulate the IP addresses so that a Cisco router will be the IGMP querier, which might be the highest or lowest IP address, depending on which version of IGMP is being run on the network. An IGMP Version 2 querier is selected based on the lowest IP addressed router on the interface. An IGMP Version 1 querier is selected based on the multicast routing protocol used on the interface.
When multiple Cisco routers are connected to a switched network and the ip cgmp proxy command is needed, we recommend that all routers be configured in the following manner:
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Examples
The following example enables CGMP:
ip cgmpThe following example enables CGMP and CGMP proxy:
ip cgmp proxyip domain multicast
To change the domain prefix used by the Cisco IOS software for Domain Name Service (DNS)-based Source Specific Multicast (SSM) mapping, use the ip domain multicast command in global configuration mode. To revert to the default domain prefix, use the no form of this command.
ip domain multicast domain-prefix
no domain multicast domain-prefix
Syntax Description
domain-prefix
Name of the domain prefix to be used for DNS-based SSM mapping. The default is in-addr.arpa.
Command Default
By default, the Cisco IOS software uses the ip-addr.arpa domain prefix.
Command Modes
Global configuration (config)
Command History
Usage Guidelines
Use this command to change the domain prefix used by Cisco IOS software when DNS-based SSM mapping is configured. When a router attempts DNS-based SSM mapping for an IP group address (G = G1.G2.G3.G4), the router queries the domain name server for IP address resource records ("IP A" RRs) for the domain G4.G3.G2.G1 domain-prefix.
Examples
The following example shows how to change the domain prefix used for DNS-based SSM mapping to ssm-map.cisco.com:
ip domain multicast ssm-map.cisco.comRelated Commands
ip dvmrp accept-filter
Note
To configure an acceptance filter for incoming Distance Vector Multicast Routing Protocol (DVMRP) reports, use the ip dvmrp accept-filter command in interface configuration mode. To disable this filter, use the no form of this command.
ip dvmrp accept-filter access-list [distance | neighbor-list access-list]
no ip dvmrp accept-filter access-list [distance | neighbor-list access-list]
Syntax Description
Defaults
All destination reports are accepted with a distance of 0. Default settings accept reports from all neighbors.
Command Modes
Interface configuration
Command History
Usage Guidelines
Any sources that match the access list are stored in the DVMRP routing table with the distance argument.
The distance value is used to compare with the same source in the unicast routing table. The route with the lower distance (either the route in the unicast routing table or that in the DVMRP routing table) takes precedence when computing the Reverse Path Forwarding (RPF) interface for a source of a multicast packet.
By default, the administrative distance for DVMRP routes is 0, which means that they always take precedence over unicast routing table routes. If you have two paths to a source, one through unicast routing (using Protocol Independent Multicast [PIM] as the multicast routing protocol) and another path using DVMRP (unicast and multicast routing), and if you want to use the PIM path, use the ip dvmrp accept-filter command to increase the administrative distance for DVMRP routes.
Examples
The following example shows how to apply an access list such that the RPF interface used to accept multicast packets will be through an Enhanced Interior Gateway Routing Protocol (IGRP)/PIM path. The Enhanced IGRP unicast routing protocol has a default administrative distance of 90.
ip dvmrp accept-filter 1 100access-list 1 permit 0.0.0.0 255.255.255.255The following example shows how to apply access list 57 to an interface and set a distance of 4:
access-list 57 permit 172.16.0.0 0.0.255.255access-list 57 permit 192.168.0.0 0.0.0.255access-list 57 deny 10.0.0.0 255.255.255.255ip dvmrp accept-filter 57 4Related Commands
ip dvmrp auto-summary
Note
To enable Distance Vector Multicast Routing Protocol (DVMRP) automatic summarization if it was disabled, use the ip dvmrp auto-summary command in interface configuration mode. To disable this function, use the no form of this command.
ip dvmrp auto-summary
no ip dvmrp auto-summary
Syntax Description
This command has no arguments or keywords.
Defaults
DVMRP automatic summarization is enabled.
Command Modes
Interface configuration
Command History
Usage Guidelines
DVMRP automatic summarization occurs when a unicast subnet route is collapsed into a classful network number route. This situation occurs when the subnet is a different network number than the IP address of the interface (or tunnel) over which the advertisement is sent. If the interface is unnumbered, the network number of the numbered interface the unnumbered interface points to is compared to the subnet.
Disable this function if the information you want to send using the ip dvmrp summary-address command is the same as the information that would be sent using DVMRP automatic summarization.
Examples
The following example shows how to disable DVMRP automatic summarization:
no ip dvmrp auto-summaryRelated Commands
ip dvmrp summary-address
Configures a DVMRP summary address to be advertised out the interface.
ip dvmrp default-information
Note
To advertise network 0.0.0.0 to Distance Vector Multicast Routing Protocol (DVMRP) neighbors on an interface, use the ip dvmrp default-information command in interface configuration mode. To prevent the advertisement, use the no form of this command.
ip dvmrp default-information {originate | only}
no ip dvmrp default-information {originate | only}
Syntax Description
originate
Specifies that other routes more specific than 0.0.0.0 may be advertised.
only
Specifies that no DVMRP routes other than 0.0.0.0 are advertised.
Defaults
Network 0.0.0.0 is not advertised to DVMRP neighbors on an interface.
Command Modes
Interface configuration
Command History
Usage Guidelines
This command should be used only when the router is a neighbor to mrouted version 3.6 devices. The mrouted protocol is a public domain implementation of DVMRP.
You can use the ip dvrmrp metric command with the ip dvmrp default-information command to tailor the metric used when advertising the default route 0.0.0.0. By default, metric 1 is used.
Examples
The following example shows how to configure a router to advertise network 0.0.0.0, in addition to other networks, to DVMRP neighbors:
ip dvmrp default-information originateRelated Commands
ip dvmrp metric
Configures the metric associated with a set of destinations for DVMRP reports.
ip dvmrp interoperability
To enable Distance Vector Multicast Routing Protocol (DVMRP) interoperability, use the ip dvmrp interoperability command in global configuration mode. To disable DVMRP interoperatibility, use the no form of this command.
ip dvmrp [vrf vrf-name] interoperability
no ip dvmrp [vrf vrf-name] interoperability
Syntax Description
vrf vrf-name
Enables DVMRP interoperability for the Multicast Virtual Private Network virtual routing and forwarding (MVRF) instance specified for the vrf-name argument.
Command Default
DVMRP interoperability is disabled by default.
Command Modes
Global configuration (config)
Command History
Usage Guidelines
Use the ip dvmrp interoperability command to enable DVMRP interoperability.
Note
When DVMRP interoperability is disabled, the router will not process DVMRP packets (probe, report, prune, or graft packets) but will still process packets that are received from mtrace and mrinfo multicast backbone (MBONE) commands.
When upgrading the router to a Cisco IOS software release where DVMRP is disabled by default, if any DVMRP commands are configured, the ip dvmrp interoperability command will automatically be nvgened during reboot.
Note
Examples
The following example shows how to enable DVMRP interoperability:
Router(config)# ip dvmrp interoperabilityip dvmrp metric
Note
To configure the metric associated with a set of destinations for Distance Vector Multicast Routing Protocol (DVMRP) reports, use the ip dvmrp metric command in interface configuration mode. To disable this function, use the no form of this command.
ip dvmrp metric metric [route-map map-name] [mbgp] [mobile] [list access-list-number] [protocol process-id] | dvmrp]
no ip dvmrp metric metric [route-map map-name] [mbgp] [mobile] [list access-list-number] [protocol process-id] | dvmrp]
Syntax Description
Defaults
No metric value is preconfigured. Only directly connected subnets and networks are advertised to neighboring DVMRP routers.
Command Modes
Interface configuration
Command History
Usage Guidelines
When Protocol Independent Multicast (PIM) is configured on an interface and DVMRP neighbors are discovered, the Cisco IOS software sends DVMRP report messages for directly connected networks. The ip dvmrp metric command enables DVMRP report messages for multicast destinations that match the access list. Usually, the metric for these routes is 1. Under certain circumstances, you might want to tailor the metric used for various unicast routes. This command lets you configure the metric associated with a set of destinations for report messages sent out this interface.
You can use the access-list-number argument in conjunction with the protocol and process-id arguments to selectively list the destinations learned from a given routing protocol.
To display DVMRP activity, use the debug ip dvmrp command.
Examples
The following example shows how to connect a PIM cloud to a DVMRP cloud. Access list 1 permits the sending of DVMRP reports to the DVMRP routers advertising all sources in the 172.16.35.0 network with a metric of 1. Access list 2 permits all other destinations, but the metric of 0 means that no DVMRP reports are sent for these destinations.
access-list 1 permit 172.16.35.0 0.0.0.255access-list 1 deny 0.0.0.0 255.255.255.255access-list 2 permit 0.0.0.0 255.255.255.255interface tunnel 0ip dvmrp metric 1 list 1ip dvmrp metric 0 list 2The following example shows how to redistribute IPv4 multicast routes into DVMRP neighbors with a metric of 1:
interface tunnel 0ip dvmrp metric 1 mbgpRelated Commands
debug ip dvmrp
Displays information on DVMRP packets received and sent.
ip dvmrp accept-filter
Configures an acceptance filter for incoming DVMRP reports.
ip dvmrp metric-offset
Note
To change the metrics of advertised Distance Vector Multicast Routing Protocol (DVMRP) routes and thus favor or not favor a certain route, use the ip dvmrp metric-offset command in interface configuration mode. To restore the default values, use the no form of this command.
ip dvmrp metric-offset [in | out] increment
no ip dvmrp metric-offset
Syntax Description
Defaults
If neither in nor out is specified, in is the default.
in: 1
out: 0Command Modes
Interface configuration
Command History
Usage Guidelines
Use this command to influence which routes are used, as you prefer. The DVMRP metric is in hop count.
Examples
The following example shows how to add a value of 10 to incoming DVMRP reports:
ip dvmrp metric-offset 10ip dvmrp output-report-delay
Note
To configure an interpacket delay of a Distance Vector Multicast Routing Protocol (DVMRP) report, use the ip dvmrp output-report-delay command in interface configuration mode. To restore the default values, use the no form of this command.
ip dvmrp output-report-delay milliseconds [burst]
no ip dvmrp output-report-delay milliseconds [burst]
Syntax Description
Defaults
milliseconds: 100 milliseconds
burst: 2 packetsCommand Modes
Interface configuration
Command History
Usage Guidelines
The delay is the number of milliseconds that elapse between transmissions of sets of packets that constitute a report. The number of packets in the set is determined by the burst value.
You might want to change the default values, depending on the CPU and buffering of the mrouted machine.
Examples
The following example shows how to set the interpacket delay to 200 milliseconds and the burst size to 3 packets. For this example, at the periodic DVMRP report interval, if six packets are built, three packets will be sent, then a delay of 200 milliseconds will occur, and then the next three packets will be sent.
ip dvmrp output-report-delay 200 3ip dvmrp reject-non-pruners
Note
To configure the router so that it will not peer with a Distance Vector Multicast Routing Protocol (DVMRP) neighbor if that neighbor does not support DVMRP pruning or grafting, use the ip dvmrp reject-non-pruners command in interface configuration mode. To disable the function, use the no form of this command.
ip dvmrp reject-non-pruners
no ip dvmrp reject-non-pruners
Syntax Description
This command has no arguments or keywords.
Defaults
Routers peer with DVMRP neighbors that do not support DVMRP pruning or grafting.
Command Modes
Interface configuration
Command History
Usage Guidelines
By default, the router accepts all DVMRP neighbors as peers, regardless of their DVMRP capability or lack thereof.
Use this command to prevent a router from peering with a DVMRP neighbor if that neighbor does not support DVMRP pruning or grafting. If the router receives a DVMRP probe or report message without the Prune-Capable flag set, the router logs a syslog message and discards the message.
This command prevents peering with neighbors only. If there are any nonpruning routers multiple hops away (downstream toward potential receivers) that are not rejected, then a nonpruning DVMRP network might still exist.
Examples
The following example shows how to configures the router not to peer with DVMRP neighbors that do not support pruning or grafting:
ip dvmrp reject-non-prunersip dvmrp routehog-notification
Note
To change the number of Distance Vector Multicast Routing Protocol (DVMRP) routes allowed before a syslog warning message is issued, use the ip dvmrp routehog-notification command in global configuration mode. To restore the default value, use the no form of this command.
ip dvmrp routehog-notification route-count
no ip dvmrp routehog-notification
Syntax Description
route-count
Number of routes allowed before a syslog message is triggered. The default is 10,000 routes.
Defaults
10,000 routes
Command Modes
Global configuration
Command History
Usage Guidelines
This command configures how many DVMRP routes are accepted on each interface within an approximate 1-minute period before a syslog message is issued, warning that a route surge might be occurring. The warning is typically used to detect quickly when routers have been misconfigured to inject a large number of routes into the multicast backbone (MBONE).
The show ip igmp interface command displays a running count of routes. When the count is exceeded, an "*** ALERT ***" is appended to the line.
Examples
The following example shows how to lower the threshold to 8000 routes:
ip dvmrp routehog-notification 8000Related Commands
show ip igmp interface
Displays multicast-related information about an interface.
ip dvmrp route-limit
Note
To change the limit on the number of Distance Vector Multicast Routing Protocol (DVMRP) routes that can be advertised over an interface enabled to run DVMRP, use the ip dvmrp route-limit command in global configuration mode. To configure no limit, use the no form of this command.
ip dvmrp route-limit count
no ip dvmrp route-limit
Syntax Description
Defaults
count: 7000 routes
Command Modes
Global configuration
Command History
Usage Guidelines
Interfaces enabled to run DVMRP include a DVMRP tunnel, an interface where a DVMRP neighbor has been discovered, and an interface configured to run the ip dvmrp unicast-routing command.
The ip dvmrp route-limit command is automatically generated to the configuration file when at least one interface is enabled for multicast routing. This command is necessary to prevent misconfigured ip dvmrp metric commands from causing massive route injection into the multicast backbone (MBONE).
Examples
The following example shows how to configure the limit of DMVRP routes that can be advertised to 5000:
ip dvmrp route-limit 5000Related Commands
ip dvmrp metric
Configures the metric associated with a set of destinations for DVMRP reports.
ip dvmrp unicast-routing
Enables DVMRP unicast routing on an interface.
ip dvmrp summary-address
Note
To configure a Distance Vector Multicast Routing Protocol (DVMRP) summary address to be advertised out the interface, use the ip dvmrp summary-address command in interface configuration mode. To remove the summary address, use the no form of this command.
ip dvmrp summary-address summary-address mask [metric value]
no ip dvmrp summary-address summary-address mask [metric value]
Syntax Description
Defaults
metric value: 1
Command Modes
Interface configuration
Command History
Usage Guidelines
If there is at least a single, more specific route in the unicast routing table that matches the specified address and mask arguments, the summary is advertised. Routes in the DVMRP routing table are not candidates for summarization.
When the metric keyword is specified, the summary is advertised with that metric value.
Multiple summary addresses can be configured on an interface. When multiple overlapping summary addresses are configured on an interface, the one with the longest mask takes preference.
Examples
The following example configures the DVMRP summary address 172.16.0.0 to be advertised out the interface:
ip dvmrp summary-address 172.16.0.0 255.255.0.0 metric 1Related Commands
ip dvmrp unicast-routing
Note
To enable Distance Vector Multicast Routing Protocol (DVMRP) unicast routing on an interface, use the ip dvmrp unicast-routing command in interface configuration mode. To disable this function, use the no form of this command.
ip dvmrp unicast-routing
no ip dvmrp unicast-routing
Syntax Description
This command has no arguments or keywords.
Defaults
DVMRP unicast routing on an interface is disabled.
Command Modes
Interface configuration
Command History
Usage Guidelines
Enabling DVMRP unicast routing means that routes in DVMRP report messages are cached by the router in a DVMRP routing table. When Protocol Independent Multicast (PIM) is running, these routes may get preference over routes in the unicast routing table. This capability allows PIM to run on the multicast backbone (MBONE) topology when it is different from the unicast topology.
DVMRP unicast routing can run on all interfaces, including generic routing encapsulation (GRE) tunnels. On DVMRP tunnels, it runs by virtue of DVMRP multicast routing. This command does not enable DVMRP multicast routing among Cisco routers. However, if there is a DVMRP-capable multicast router, the Cisco router will do PIM and DVMRP multicast routing interaction.
Examples
The following example shows how to enable DVMRP unicast routing:
ip dvmrp unicast-routingRelated Commands
ip dvmrp route-limit
Changes the limit on the number of DVMRP routes that can be advertised over an interface enabled to run DVMRP.
