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This feature module describes the IP multicast Multilayer Switching (MLS) feature. It includes the following sections:
The IP multicast MLS feature provides high-performance, hardware-based, Layer 3 switching of IP multicast traffic for routers connected to Catalyst 5000 series LAN switches.
An IP multicast flow is a unidirectional sequence of packets between a multicast source and the members of a destination multicast group. Flows are based on the IP address of the source device and the destination IP multicast group address.
The packet forwarding function is moved onto the connected Layer 3 switch whenever a supported path exists between a source and members of a multicast group. Packets that do not have a supported path to reach their destinations are still forwarded in software by routers. Protocol Independent Multicast (PIM) is used for route determination.
An IP multicast MLS network topology has two components:
The MMLS-SE uses the Layer 2 multicast forwarding table to determine on which ports Layer 2 multicast traffic should be forwarded (if any). The Layer 2 multicast forwarding table is populated by enabling CGMP, IGMP snooping, or GMRP on the switch. These entries map the destination multicast MAC address to outgoing switch ports for a given VLAN.
The MMLS-SE maintains the Layer 3 MLS cache to identify individual IP multicast flows. Each entry is of the form {source IP, destination group IP, source VLAN}. The maximum MLS cache size is 128K and is shared by all MLS processes on the switch (such as IP unicast MLS and IPX MLS). However, if the total of cache entries exceeds 32K, there is increased probability that a flow will not be switched by the MMLS-SE and will get forwarded to the router.
The MMLS-SE populates the MLS cache using information learned from the routers participating in IP multicast MLS. The router and switch exchange information using the multicast Multilayer Switching Protocol (multicast MLSP).
Whenever the router receives traffic for a new flow, it updates its multicast routing table and forwards the new information to the MMLS-SE using multicast MLSP. In addition, if an entry in the multicast routing table is aged out, the router deletes the entry and forwards the updated information to the MMLS-SE.
The MLS cache contains flow information for all active multilayer switched flows. After the MLS cache is populated, multicast packets identified as belonging to an existing flow can be Layer 3-switched based on the cache entry for that flow. For each cache entry, the MMLS-SE maintains a list of outgoing interfaces for the destination IP multicast group. The MMLS-SE uses this list to determine on which VLANs traffic to a given multicast flow should be replicated.
IP multicast MLS supports a single flow mask, source-destination-vlan. The MMLS-SE maintains one multicast MLS cache entry for each {source IP, destination group IP, source VLAN}. The multicast source-destination-vlan flow mask differs from the IP unicast MLS source-destination-ip flow mask in that, for IP multicast MLS, the source VLAN is included as part of the entry. The source VLAN is the multicast Reverse Path Forwarding (RPF) interface for the multicast flow.
When a multicast packet is Layer 3-switched from a multicast source to a destination multicast group, the MMLS-SE performs a packet rewrite based on information learned from the MMLS-RP and stored in the multicast MLS cache.
For example, if Server A sends a multicast packet addressed to IP multicast group G1 and members of group G1 are on VLANs other than the source VLAN, the MMLS-SE must perform a packet rewrite when it replicates the traffic to the other VLANs (the switch also bridges the packet in the source VLAN).
When the MMLS-SE receives the multicast packet, it is formatted similarly to the sample that follows (only the important fields are shown):
| Frame Header | IP Header | Payload | |||||
|---|---|---|---|---|---|---|---|
Destination | Source | Destination | Source | TTL | Checksum | Data | Checksum |
Group G1 MAC | Server A MAC | Group G1 IP | Server A IP | n | calculation1 | ||
The MMLS-SE rewrites the packet as follows:
The result is a rewritten IP multicast packet that appears to have been routed by the router. The MMLS-SE replicates the rewritten packet onto the appropriate destination VLANs, where it is forwarded to members of IP multicast group G1.
After the MMLS-SE performs the packet rewrite, the packet is formatted as follows:
| Frame Header | IP Header | Payload | |||||
|---|---|---|---|---|---|---|---|
Destination | Source | Destination | Source | TTL | Checksum | Data | Checksum |
Group G1 MAC | MMLS-RP MAC | Group G1 IP | Server A IP | n - 1 | calculation2 | ||
When at least one outgoing router interface for a given flow is multilayer switched, and at least one outgoing interface is not multilayer switched, that flow is considered partially switched. When a partially switched flow is created, all multicast traffic belonging to that flow still reaches the router and is software forwarded on those outgoing interfaces that are not multilayer switched.
A flow might be partially switched instead of completely switched in these situations:
When all the outgoing router interfaces for a given flow are multilayer switched, and none of the above situations apply to the flow, that flow is considered completely switched. When a completely switched flow is created, the MMLS-SE prevents multicast traffic bridged on the source VLAN for that flow from reaching the MMLS-RP interface in that VLAN, reducing the load on the router.
One consequence of a completely switched flow is that the router cannot record multicast statistics for that flow. Therefore, the MMLS-SE periodically sends multicast packet and byte count statistics for all completely switched flows to the router using multicast MLSP. The router updates the corresponding multicast routing table entry and resets the expiration timer for that multicast route.
IP multicast MLS requires specific network topologies to function correctly. In each of these topologies, the source traffic is received on the switch, traverses a trunk link to the router, and returns to the switch over the same trunk link to reach the destination group members. The basic topology consists of a switch and an internal or external router connected through an ISL or 802.1Q trunk link.
Figure 1 shows this basic configuration before and after IP multicast MLS is deployed (assuming a completely switched flow). The topology consists of a switch, a directly connected external router, and multiple IP subnetworks (VLANs).
The network in the upper diagram in Figure 1 does not have the IP multicast MLS feature enabled. Note the arrows from the router to each multicast group in each VLAN. In this case, the router must replicate the multicast data packets to the multiple VLANs. The router can be easily overwhelmed with forwarding and replicated multicast traffic if the input rate or the number of outgoing interfaces increases.
As shown in the lower diagram in Figure 1, this potential problem is prevented by having the switch hardware forward the multicast data traffic. (Multicast control packets are still moving between the router and switch.)
This feature improves the router's multicast Layer 3 forwarding and replication throughput.
If the router must replicate many multicast packets to many VLANs, it can be overwhelmed as the input rate and number of outgoing interfaces increase. Configuring the switch to replicate and forward the multicast flow reduces the demand on the router.
If you need high throughput of multicast traffic, install a Catalyst 5000 series switch and configure this feature. By reducing the load on your router, you can accommodate more multicast flows.
IP multicast MLS provides flow statistics that can be used to administer, plan, and troubleshoot networks.
You must also configure the Catalyst 5000 series switch in order for IP multicast MLS to function on the router.
The restrictions in the following sections apply to IP multicast MLS on the router:
IP multicast MLS does not work on internal or external routers in the following situations:
Follow these guidelines when using an external router:
These restrictions apply when using access lists on interfaces participating in IP multicast MLS:
Router(config)# access-list 101 permit udp any any Router(config)# access-list 101 permit ip any any
Router(config)# access-list 101 permit udp s1 g1 Router(config)# access-list 101 permit ip any any
If IP multicast MLS is enabled, IP accounting for the interface will not reflect accurate values.
The first five platforms listed are external routers; the last two platforms have internal routers:
No new or modified MIBs are supported by this feature.
For descriptions of supported MIBs and how to use MIBs, see the Cisco MIB web site on CCO at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.
None
None
The following prerequisites are necessary before MLS can function:
See the following sections for configuration tasks for IP multicast MLS. Each task in the list indicates whether it is optional or required.
For examples of IP multicast MLS configurations, see the "Configuration Examples" section later in this document.
You must enable IP multicast routing globally on the MMLS-RPs before you can enable IP multicast MLS on router interfaces. To enable IP multicast routing on the router, use the following command:
| Command | Purpose |
|---|---|
Router(config)# ip multicast-routing | Enables IP multicast routing globally. |
You must enable Protocol Independent Multicast (PIM) on the router interfaces connected to the switch before IP multicast MLS will function on those router interfaces. To do so, use the following commands:
| Step | Command | Purpose | ||
|---|---|---|---|---|
| Router(config)# interface type number | Configures an interface. | ||
| Router(config-if)# ip pim {dense-mode | sparse-mode | sparse-dense-mode} | Enables PIM on the interface. |
IP multicast MLS is enabled by default when you enable PIM on the interface. Perform this task only if you disabled IP multicast MLS and you want to reenable it. To enable IP multicast MLS on an interface, use the following command:
| Command | Purpose |
|---|---|
Router(config-if)# mls rp ip multicast |
When you enable IP multicast MLS, the subinterface (or VLAN interface) that has the lowest VLAN ID and is active (in the "up" state) is automatically selected as the management interface. The one-hop protocol Multilayer Switching Protocol (MLSP) is used between a router and a switch to pass messages about hardware-switched flows. MLSP packets are sent and received on the management interface. Typically, the interface in VLAN 1 is chosen (if that interface exists). Only one management interface is allowed on a single trunk link.
In most cases, we recommend that the management interface be determined by default. However, you can optionally specify a different router interface or subinterface as the management interface. We recommend using a subinterface with minimal data traffic so that multicast MLSP packets can be sent and received more quickly.
If the user-configured management interface goes down, the router uses the default interface (the active interface with the lowest VLAN ID) until the user-configured interface comes up again.
To change the default IP multicast MLS management interface, use the following command:
| Command | Purpose |
|---|---|
Router(config-if)# mls rp ip multicast management-interface | Configures an interface as the IP multicast MLS management interface. |
| Command | Purpose |
|---|---|
Router# show ip mroute [group-name | group-address [source]] | Displays hardware switching state for outgoing interfaces. |
Router# show ip pim interface [type number] [count] | Displays PIM interface information. |
Router# show mls rp ip multicast [locate] [group [source] [vlan-id]] | [statistics] | [summary] | Displays Layer 3 switching information. |
These sections contain example IP multicast MLS implementations. These examples include the switch configurations, although switch commands are not documented in this router publication. Refer to the Catalyst 5000 Command Reference for that information.
This example consists of these sections:
Figure 2 shows a basic IP multicast MLS example network topology.
The network is configured as follows:
Without IP multicast MLS, when the G1 source (on VLAN 10) sends traffic destined for IP multicast group G1, the switch forwards the traffic (based on the Layer 2 multicast forwarding table entry generated by the IGMP snooping, CGMP, or GMRP multicast service) to Host A on VLAN 10 and to the router subinterface in VLAN 10.
The router receives the multicast traffic on its incoming subinterface for VLAN 10, checks the multicast routing table, and replicates the traffic to the outgoing subinterfaces for VLANs 20 and 30. The switch receives the traffic on VLANs 20 and 30 and forwards the traffic received on these VLANs to the appropriate switch ports, again based on the contents of the Layer 2 multicast forwarding table.
After IP multicast MLS is implemented, when the G1 source sends traffic destined for multicast group G1, the MMLS-SE checks its Layer 3 multicast MLS cache and recognizes that the traffic belongs to a multicast MLS flow. The MMLS-SE forwards the traffic to Host A on VLAN 10 based on the multicast forwarding table, but does not forward the traffic to the router subinterface in VLAN 10 (assuming a completely switched flow).
For each multicast MLS cache entry, the switch maintains a list of outgoing interfaces for the destination IP multicast group. The switch replicates the traffic on the appropriate outgoing interfaces (VLANs 20 and 30) and then forwards the traffic on each VLAN to the destination hosts (using the Layer 2 multicast forwarding table). The switch performs a packet rewrite for the replicated traffic so that the packets appear to have been routed by the appropriate router subinterface.
If not all the router subinterfaces are eligible to participate in IP multicast MLS, the switch must forward the multicast traffic to the router subinterface in the source VLAN (in this case, VLAN 10). In this situation, on those subinterfaces that are ineligible, the router performs multicast forwarding and replication in software, in the usual manner. On those subinterfaces that are eligible, the switch performs multilayer switching.
The following is an example configuration of IP multicast MLS on the router:
ip multicast-routing interface fastethernet2/0.10 encapsulation isl 10 ip address 10.1.10.1 255.255.255.0 ip pim dense-mode interface fastethernet2/0.20 encapsulation isl 20 ip address 10.1.20.1 255.255.255.0 ip pim dense-mode interface fastethernet2/0.30 encapsulation isl 30 ip address 10.1.30.1 255.255.255.0 ip pim dense-mode mls rp ip multicast management-interface
You will receive the following message informing you that you changed the management interface:
Warning: MLS Multicast management interface is now Fa2/0.30
The following example shows how to configure the switch (MMLS-SE):
Console> (enable) set trunk 1/2 on isl Port(s) 1/2 trunk mode set to on. Port(s) 1/2 trunk type set to isl. Console> (enable) set igmp enable IGMP feature for IP multicast enabled Console> (enable) set mls multicast enable Multilayer Switching for Multicast is enabled for this device. Console> (enable) set mls multicast include 10.1.10.1 Multilayer switching for multicast is enabled for router 10.1.10.1.
This example consists of these sections:
Figure 3 shows a more complex IP multicast MLS example network topology.
The network is configured as follows:
Without IP multicast MLS, when Server A (on VLAN 10) sends traffic destined for IP multicast group G1, Switch B forwards the traffic (based on the Layer 2 multicast forwarding table entry) to Host A on VLAN 10 and to Switch A. Switch A forwards the traffic to the Router A and Router B subinterfaces in VLAN 10.
Router A receives the multicast traffic on its incoming subinterface for VLAN 10, checks the multicast routing table, and replicates the traffic to the outgoing subinterface for VLAN 20. Router B receives the multicast traffic on its incoming interface for VLAN 10, checks the multicast routing table, and replicates the traffic to the outgoing subinterface for VLAN 30.
Switch A receives the traffic on VLANs 20 and 30. Switch A forwards VLAN 20 traffic to the appropriate switch ports (in this case, to Host C), based on the contents of the Layer 2 multicast forwarding table. Switch A forwards the VLAN 30 traffic to Switch C.
Switch C receives the VLAN 30 traffic and forwards it to the appropriate switch ports (in this case, Hosts D and E) using the multicast forwarding table.
After IP multicast MLS is implemented, when Server A sends traffic destined for multicast group G1, Switch B forwards the traffic (based on the Layer 2 multicast forwarding table entry) to Host A on VLAN 10 and to Switch A.
Switch A checks its Layer 3 multicast MLS cache and recognizes that the traffic belongs to a multicast MLS flow. Switch A does not forward the traffic to the router subinterfaces in VLAN 10 (assuming a completely switched flow). Instead, Switch A replicates the traffic on the appropriate outgoing interfaces (VLANs 20 and 30).
VLAN 20 traffic is forwarded to Host C and VLAN 30 traffic is forwarded to Switch C (based on the contents of the Layer 2 multicast forwarding table). The switch performs a packet rewrite for the replicated traffic so that the packets appear to have been routed by the appropriate router subinterface.
Switch C receives the VLAN 30 traffic and forwards it to the appropriate switch ports (in this case, Hosts D and E) using the multicast forwarding table.
If not all the router subinterfaces are eligible to participate in IP multicast MLS, the switch must forward the multicast traffic to the router subinterfaces in the source VLAN (in this case, VLAN 10). In this situation, on those subinterfaces that are ineligible, the routers perform multicast forwarding and replication in software in the usual manner. On those subinterfaces that are eligible, the switch performs multilayer switching.
ip multicast-routing interface fastethernet1/0.1 encapsulation isl 1 ip address 172.20.1.1 255.255.255.0 interface fastethernet1/0.10 encapsulation isl 10 ip address 172.20.10.1 255.255.255.0 ip pim dense-mode interface fastethernet1/0.20 encapsulation isl 20 ip address 172.20.20.1 255.255.255.0 ip pim dense-mode
ip multicast-routing interface fastethernet1/0.1 encapsulation isl 1 ip address 172.20.1.2 255.255.255.0 interface fastethernet2/0.10 encapsulation isl 10 ip address 172.20.10.100 255.255.255.0 ip pim dense-mode interface fastethernet2/0.30 encapsulation isl 30 ip address 172.20.30.100 255.255.255.0 ip pim dense-mode
Console> (enable) set vlan 10 Vlan 10 configuration successful Console> (enable) set vlan 20 Vlan 20 configuration successful Console> (enable) set vlan 30 Vlan 30 configuration successful Console> (enable) set trunk 1/1 on isl Port(s) 1/1 trunk mode set to on. Port(s) 1/1 trunk type set to isl. Console> (enable) set trunk 1/2 on isl Port(s) 1/2 trunk mode set to on. Port(s) 1/2 trunk type set to isl. Console> (enable) set trunk 1/3 desirable isl Port(s) 1/3 trunk mode set to desirable. Port(s) 1/3 trunk type set to isl. Console> (enable) set trunk 1/4 desirable isl Port(s) 1/4 trunk mode set to desirable. Port(s) 1/4 trunk type set to isl. Console> (enable) set igmp enable IGMP feature for IP multicast enabled Console> (enable) set mls multicast enable Multilayer Switching for Multicast is enabled for this device. Console> (enable) set mls multicast include 172.20.10.1 Multilayer switching for multicast is enabled for router 172.20.10.1. Console> (enable) set mls multicast include 172.20.10.100 Multilayer switching for multicast is enabled for router 172.20.10.100. Console> (enable)
The following example shows how to configure Switch B (assuming VLAN Trunking Protocol [VTP] is used for VLAN management):
Console> (enable) set igmp enable IGMP feature for IP multicast enabled Console> (enable)
The following example shows how to configure Switch C (assuming VTP is used for VLAN management):
Console> (enable) set igmp enable IGMP feature for IP multicast enabled Console> (enable)
This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.0 command reference publications and the Catalyst 5000 Software Configuration Guide and Catalyst 5000 Command Reference, Release 5.1.
In Cisco IOS Release 12.0(1)T or later, you can search and filter the output for show and more commands. This functionality is useful when you need to sort through large amounts of output, or if you want to exclude output that you do not need to see.
To use this functionality, enter a show or more command followed by the "pipe" character (|), one of the keywords begin, include, or exclude, and an expression that you want to search or filter on:
command | {begin | include | exclude} regular-expression
Following is an example of the show atm vc command in which you want the command output to begin with the first line where the expression "PeakRate" appears:
show atm vc | begin PeakRate
For more information on the search and filter functionality, refer to the Cisco IOS Release 12.0(1)T feature module entitled CLI String Search.
To delete entries from the IP multicast routing table, use the clear ip mroute EXEC command.
clear ip mroute {* | group [source]}
* | Deletes all entries from the IP multicast routing table. |
group | Can be either one of the following: · Name of the multicast group, as defined in the DNS hosts table or with the ip host command. · IP address of the multicast group. This is a multicast IP address in four-part, dotted notation. |
source | (Optional) If you specify a group name or address, you can also specify a name or address of a multicast source that is sending to the group. A source need not be a member of the group. |
EXEC
| Release | Modification |
|---|---|
10.0 | This command was introduced. |
12.0(5)T | The effect of this command was modified. If IP multicast Multilayer Switching (MLS) is enabled, using this command now clears both the multicast routing table on the MMLS-RP and all multicast MLS cache entries for all MMLS-SEs that are performing multicast MLS for the MMLS-RP. That is, the original clearing occurs, and the derived hardware switching table is also cleared. |
The following example deletes all entries from the IP multicast routing table:
clear ip mroute *
The following example deletes from the IP multicast routing table all sources on the 10.3.0.0 subnet that are sending to the multicast group 224.2.205.42. Note that this example deletes all sources on network 10.3, not individual sources.
clear ip mroute 224.2.205.42 10.3.0.0
| Command | Description |
ip host | Statically maps a host name to an IP address. |
Enables IP multicast MLS. | |
show ip mroute | Displays the contents of the IP multicast routing table. |
To enable IP multicast routing, use the ip multicast-routing global configuration command. To disable IP multicast routing, use the no form of this command.
ip multicast-routingThis command has no arguments or keywords.
Disabled
Global configuration
| Release | Modification |
|---|---|
10.0 | This command was introduced. |
12.0(5)T | The effect of this command was modified. If IP multicast Multilayer Switching (MLS) is enabled, using the no form of this command now disables IP multicast routing on the MMLS-RP and purges all multicast MLS cache entries on the MMLS-SE. |
When IP multicast routing is disabled, the Cisco IOS software does not forward any multicast packets.
The following example enables IP multicast routing:
ip multicast-routing
| Command | Description |
ip pim | Enables PIM and IGMP on an interface. |
To enable IP multicast Multilayer Switching (hardware switching) on an external or internal router in conjunction with Layer 3 switching hardware for the Catalyst 5000, use the mls rp ip multicast interface configuration command. Use the no form of the command to disable IP multicast Multilayer Switching (MLS) on the interface or VLAN.
mls rp ip multicastThis command has no arguments or keywords.
Enabled
Interface configuration
| Release | Modification |
|---|---|
12.0(5)T | This command was introduced. |
This feature is available only on specific router platforms connected to a Catalyst 5000 switch. Use this feature to reduce multicast load on the router. The switch will perform the multicast packet replication and forwarding.
IP multicast MLS is enabled by default on an interface once IP multicast routing and PIM are enabled.
The following example disables IP multicast MLS:
interface fastethernet1/0.1
no mls rp ip multicast
| Command | Description |
Assigns a management interface other than the default. | |
Enables complete flows for IP multicast MLS. | |
Displays hardware-switched multicast flow information about IP multicast MLS. |
To assign a different interface (other than the default) to act as the management interface for Multilayer Switching Protocol (MLSP) , use the mls rp ip multicast management-interface interface configuration command. Use the no form of the command to restore the default interface as the management interface.
mls rp ip multicast management-interfaceThis command has no arguments or keywords.
When IP multicast MLS is enabled, the subinterface (or VLAN interface) that has the lowest VLAN ID and is active (in the "up" state) is automatically selected as the management interface.
Interface configuration
| Release | Modification |
|---|---|
12.0(5)T | This command was introduced. |
When you enable IP multicast MLS, the subinterface (or VLAN interface) that has the lowest VLAN ID and is active (in the "up" state) is automatically selected as the management interface. The one-hop protocol Multilayer Switching Protocol (MLSP) is used between a router and a switch to pass messages about hardware-switched flows. MLSP packets are sent and received on the management interface. Typically, the interface in VLAN 1 is chosen (if that interface exists). Only one management interface is allowed on a single trunk link.
In most cases, we recommend that the management interface be determined by default. However, you can optionally use this command to specify a different router interface or subinterface as the management interface. We recommend using a subinterface with minimal data traffic so that multicast MLSP packets can be transmitted and received more quickly.
If the user-configured management interface goes down, the router uses the default interface (the active interface with the lowest VLAN ID) until the user-configured interface comes up again.
The following example configures the Fast Ethernet interface as the management interface:
interface fastethernet1/0.1
mls rp ip multicast management-interface
| Command | Description |
Enables IP multicast MLS. |
To display the contents of the IP multicast routing table, use the show ip mroute EXEC command.
show ip mroute [group-name | group-address] [source] [summary] [count] [active kbps]
group-name | group-address | (Optional) IP address, name, or interface of the multicast group as defined in the DNS hosts table. |
source | (Optional) IP address or name of a multicast source. |
summary | (Optional) Displays a one-line, abbreviated summary of each entry in the IP multicast routing table. |
count | (Optional) Displays statistics about the group and source, including number of packets, packets per second, average packet size, and bits per second. |
active kbps | (Optional) Displays the rate that active sources are sending to multicast groups. Active sources are those sending at a rate of kbps or higher. The kbps argument defaults to 4 kilobits per second (kbps). |
The show ip mroute command displays all groups and sources.
The show ip mroute active command displays all sources sending at a rate greater than or equal to 4 kbps.
EXEC
| Release | Modification |
|---|---|
10.0 | This command was introduced. |
12.0(5)T | The flag "H" was added in the output display to indicate that an outgoing interface is hardware switched in the case of IP multicast Multilayer Switching (MLS). |
If you omit all optional arguments and keywords, the show ip mroute command displays all entries in the IP multicast routing table.
The Cisco IOS software populates the multicast routing table by creating source, group (S,G) entries from star, group (*,G) entries. The star refers to all source addresses, the "S" refers to a single source address, and the "G" is the destination multicast group address. In creating (S,G) entries, the software uses the best path to that destination group found in the unicast routing table (that is, through Reverse Path Forwarding [RPF]).
The following is sample output from the show ip mroute command for a router operating in dense mode. This command displays the contents of the IP multicast routing table for the multicast group named cbone-audio.
Router# show ip mroute cbone-audio
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, C - Connected, L - Local, P - Pruned
R - RP-bit set, F - Register flag, T - SPT-bit set
Timers: Uptime/Expires
Interface state: Interface, Next-Hop, State/Mode
(*, 224.0.255.1), uptime 0:57:31, expires 0:02:59, RP is 0.0.0.0, flags: DC
Incoming interface: Null, RPF neighbor 0.0.0.0, Dvmrp
Outgoing interface list:
Ethernet0, Forward/Dense, 0:57:31/0:02:52
Tunnel0, Forward/Dense, 0:56:55/0:01:28
(198.92.37.100/32, 224.0.255.1), uptime 20:20:00, expires 0:02:55, flags: C
Incoming interface: Tunnel0, RPF neighbor 10.20.37.33, Dvmrp
Outgoing interface list:
Ethernet0, Forward/Dense, 20:20:00/0:02:52
The following is sample output from the show ip mroute command for a router operating in sparse mode:
Router# show ip mroute
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, C - Connected, L - Local, P - Pruned
R - RP-bit set, F - Register flag, T - SPT-bit set
Timers: Uptime/Expires
Interface state: Interface, Next-Hop, State/Mode
(*, 224.0.255.3), uptime 5:29:15, RP is 198.92.37.2, flags: SC
Incoming interface: Tunnel0, RPF neighbor 10.3.35.1, Dvmrp
Outgoing interface list:
Ethernet0, Forward/Sparse, 5:29:15/0:02:57
(198.92.46.0/24, 224.0.255.3), uptime 5:29:15, expires 0:02:59, flags: C
Incoming interface: Tunnel0, RPF neighbor 10.3.35.1
Outgoing interface list:
Ethernet0, Forward/Sparse, 5:29:15/0:02:57
The following is sample output from the show ip mroute command that shows the VCD value, because an ATM interface with PIM multipoint signalling is enabled:
Router# show ip mroute 224.1.1.1
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, C - Connected, L - Local, P - Pruned
R - RP-bit set, F - Register flag, T - SPT-bit set, J - Join SPT
Timers: Uptime/Expires
Interface state: Interface, Next-Hop or VCD, State/Mode
(*, 224.1.1.1), 00:03:57/00:02:54, RP 130.4.101.1, flags: SJ
Incoming interface: Null, RPF nbr 0.0.0.0
Outgoing interface list:
ATM0/0, VCD 14, Forward/Sparse, 00:03:57/00:02:53
The following is sample output from the show ip mroute command with the summary keyword:
Router# show ip mroute summary
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, C - Connected, L - Local, P - Pruned
R - RP-bit set, F - Register flag, T - SPT-bit set, J - Join SPT
Timers: Uptime/Expires
Interface state: Interface, Next-Hop, State/Mode
(*, 224.255.255.255), 2d16h/00:02:30, RP 171.69.10.13, flags: SJPC
(*, 224.2.127.253), 00:58:18/00:02:00, RP 171.69.10.13, flags: SJC
(*, 224.1.127.255), 00:58:21/00:02:03, RP 171.69.10.13, flags: SJC
(*, 224.2.127.254), 2d16h/00:00:00, RP 171.69.10.13, flags: SJCL
(128.9.160.67/32, 224.2.127.254), 00:02:46/00:00:12, flags: CLJT
(129.48.244.217/32, 224.2.127.254), 00:02:15/00:00:40, flags: CLJT
(130.207.8.33/32, 224.2.127.254), 00:00:25/00:02:32, flags: CLJT
(131.243.2.62/32, 224.2.127.254), 00:00:51/00:02:03, flags: CLJT
(140.173.8.3/32, 224.2.127.254), 00:00:26/00:02:33, flags: CLJT
(171.69.60.189/32, 224.2.127.254), 00:03:47/00:00:46, flags: CLJT
The following is sample output from the show ip mroute command with the active keyword:
Router# show ip mroute active
Active IP Multicast Sources - sending >= 4 kbps
Group: 224.2.127.254, (sdr.cisco.com)
Source: 146.137.28.69 (mbone.ipd.anl.gov)
Rate: 1 pps/4 kbps(1sec), 4 kbps(last 1 secs), 4 kbps(life avg)
Group: 224.2.201.241, ACM 97
Source: 130.129.52.160 (webcast3-e1.acm97.interop.net)
Rate: 9 pps/93 kbps(1sec), 145 kbps(last 20 secs), 85 kbps(life avg)
Group: 224.2.207.215, ACM 97
Source: 130.129.52.160 (webcast3-e1.acm97.interop.net)
Rate: 3 pps/31 kbps(1sec), 63 kbps(last 19 secs), 65 kbps(life avg)
The following is sample output from the show ip mroute command with the count keyword:
Router# show ip mroute count IP Multicast Statistics - Group count: 8, Average sources per group: 9.87 Counts: Pkt Count/Pkts per second/Avg Pkt Size/Kilobits per second Group: 224.255.255.255, Source count: 0, Group pkt count: 0 RP-tree: 0/0/0/0 Group: 224.2.127.253, Source count: 0, Group pkt count: 0 RP-tree: 0/0/0/0 Group: 224.1.127.255, Source count: 0, Group pkt count: 0 RP-tree: 0/0/0/0 Group: 224.2.127.254, Source count: 9, Group pkt count: 14 RP-tree: 0/0/0/0 Source: 128.2.6.9/32, 2/0/796/0 Source: 128.32.131.87/32, 1/0/616/0 Source: 128.125.51.58/32, 1/0/412/0 Source: 130.207.8.33/32, 1/0/936/0 Source: 131.243.2.62/32, 1/0/750/0 Source: 140.173.8.3/32, 1/0/660/0 Source: 146.137.28.69/32, 1/0/584/0 Source: 171.69.60.189/32, 4/0/447/0 Source: 204.162.119.8/32, 2/0/834/0 Group: 224.0.1.40, Source count: 1, Group pkt count: 3606 RP-tree: 0/0/0/0 Source: 171.69.214.50/32, 3606/0/48/0, RPF Failed: 1203 Group: 224.2.201.241, Source count: 36, Group pkt count: 54152 RP-tree: 7/0/108/0 Source: 13.242.36.83/32, 99/0/123/0 Source: 36.29.1.3/32, 71/0/110/0 Source: 128.9.160.96/32, 505/1/106/0 Source: 128.32.163.170/32, 661/1/88/0 Source: 128.115.31.26/32, 192/0/118/0 Source: 128.146.111.45/32, 500/0/87/0 Source: 128.183.33.134/32, 248/0/119/0 Source: 128.195.7.62/32, 527/0/118/0 Source: 128.223.32.25/32, 554/0/105/0 Source: 128.223.32.151/32, 551/1/125/0 Source: 128.223.156.117/32, 535/1/114/0 Source: 128.223.225.21/32, 582/0/114/0 Source: 129.89.142.50/32, 78/0/127/0 Source: 129.99.50.14/32, 526/0/118/0 Source: 130.129.0.13/32, 522/0/95/0 Source: 130.129.52.160/32, 40839/16/920/161 Source: 130.129.52.161/32, 476/0/97/0 Source: 130.221.224.10/32, 456/0/113/0 Source: 132.146.32.108/32, 9/1/112/0
The following example of show ip mroute is displayed when IP multicast MLS is configured. Note that the "H" indicates hardware switched.
Router# show ip mroute
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, C - Connected, L - Local, P - Pruned
R - RP-bit set, F - Register flag, T - SPT-bit set, J - Join SPT, H - Hardware switched
Timers: Uptime/Expires
(*, 229.10.0.1), 00:04:35/00:02:59, RP 0.0.0.0, flags: DJC
Incoming interface: Null, RPF nbr 0.0.0.0
Outgoing interface list:
Vlan6, Forward/Dense, 00:00:30/00:02:30
Vlan5, Forward/Dense, 00:04:35/00:02:30
Vlan2, Forward/Dense, 00:01:28/00:00:00
(192.0.2.20, 229.10.0.1), 00:04:35/00:02:27, flags: CT
Incoming interface: Vlan2, RPF nbr 0.0.0.0
Outgoing interface list:
Vlan5, Forward/Dense, 00:03:25/00:00:00, H
Vlan6, Forward/Dense, 00:00:10/00:00:00, H
Table 1 describes the fields shown in the displays.
| Field | Description |
|---|---|
Flags: | Provides information about the entry. |
D - Dense | Entry is operating in dense mode. |
S - Sparse | Entry is operating in sparse mode. |
C - Connected | A member of the multicast group is present on the directly connected interface. |
L - Local | The router itself is a member of the multicast group. |
P - Pruned | Route has been pruned. The Cisco IOS software keeps this information in case a downstream member wants to join the source. |
R - Rp-bit set | Indicates that the (S,G) entry is pointing toward the rendezvous point (RP). This is typically prune state along the shared tree for a particular source. |
F - Register flag | Indicates that the software is registering for a multicast source. |
T - SPT-bit set | Indicates that packets have been received on the shortest path source tree. |
J - Join SPT |
|
H - Hardware switched | Indicates the outgoing interface is hardware switched because IP multicast MLS is enabled. |
Timers: | Uptime/Expires. |
Interface state: | Interface, Next-Hop or VCD, State/Mode. |
(*, 224.0.255.1) | Entry in the IP multicast routing table. The entry consists of the IP address of the source router followed by the IP address of the multicast group. An asterisk (*) in place of the source router indicates all sources. Entries in the first format are referred to as (*,G) or "star comma G" entries. Entries in the second format are referred to as (S,G) or "S comma G" entries. (*,G) entries are used to build (S,G) entries. |
uptime | How long in hours, minutes, and seconds the entry has been in the IP multicast routing table. |
expires | How long in hours, minutes, and seconds until the entry will be removed from the IP multicast routing table on the outgoing interface. |
RP | Address of the rendezvous point (RP) router. For routers and access servers operating in sparse mode, this address is always 0.0.0.0. |
flags: | Information about the entry. |
Incoming interface: | Expected interface for a multicast packet from the source. If the packet is not received on this interface, it is discarded. |
RPF neighbor | IP address of the upstream router to the source. "Tunneling" indicates that this router is sending data to the RP encapsulated in Register packets. The hexadecimal number in parentheses indicates to which RP it is registering. Each bit indicates a different RP if multiple RPs per group are used. |
Dvmrp or Mroute | Indicates if the RPF information is obtained from the DVMRP routing table or the static mroutes configuration. |
Outgoing interface list: | Interfaces through which packets will be forwarded. When the ip pim nbma-mode command is enabled on the interface, the IP address of the PIM neighbor is also displayed. |
Ethernet0 | Name and number of the outgoing interface. |
Next hop or VCD | Next hop specifies downstream neighbor's IP address. VCD is the virtual circuit descriptor number. VCD0 means the group is using the static-map virtual circuit. |
Forward/Dense | Indicates that packets will be forwarded on the interface if there are no restrictions due to access lists or TTL threshold. Following the slash (/) is the mode in which the interface is operating (dense or sparse). |
Forward/Sparse | Sparse mode interface is in forward mode. |
time/time | Per interface, how long in hours, minutes, and seconds the entry has been in the IP multicast routing table. Following the slash (/) is how long in hours, minutes, and seconds until the entry will be removed from the IP multicast routing table. |
| Command | Description |
ip multicast routing | Enables IP multicast routing. |
ip pim | Enables PIM and IGMP on an interface. |
To display information about interfaces configured for Protocol Independent Multicast (PIM), use the show ip pim interface EXEC command.
show ip pim interface [type number] [count]
type | (Optional) Interface type. |
number | (Optional) Interface number. |
count | (Optional) Number of packets received and sent out the interface. |
EXEC
| Release | Modification |
|---|---|
10.0 | This command was introduced. |
12.0(5)T | The flag "H" was added in the output display to indicate that an outgoing interface is hardware switched in the case of IP multicast Multilayer Switching (MLS). |
This command works only on interfaces that are configured for PIM.
The following is sample output from the show ip pim interface command:
Router# show ip pim interface
Address Interface Mode Neighbor Query DR
Count Interval
198.92.37.6 Ethernet0 Dense 2 30 198.92.37.33
198.92.36.129 Ethernet1 Dense 2 30 198.92.36.131
10.1.37.2 Tunnel0 Dense 1 30 0.0.0.0
The following is sample output from the show ip pim interface command with a count:
Router# show ip pim interface count Address Interface FS Mpackets In/Out 171.69.121.35 Ethernet0 * 548305239/13744856 171.69.121.35 Serial0.33 * 8256/67052912 198.92.12.73 Serial0.1719 * 219444/862191
The following is sample output from the show ip pim interface command with a count when IP multicast MLS is enabled. The examples lists the PIM interfaces that are fast switched and process switched, and the packet counts for these. The "H" is added to interfaces where IP multicast MLS is enabled.
Router# show ip pim interface count States: FS - Fast Switched, H - Hardware Switched Address Interface FS Mpackets In/Out 192.1.10.2 Vlan10 * H 40886/0 192.1.11.2 Vlan11 * H 0/40554 192.1.12.2 Vlan12 * H 0/40554 192.1.23.2 Vlan23 * 0/0 192.1.24.2 Vlan24 * 0/0
Table 2 describes the fields shown in the displays.
| Command | Description |
ip pim | Enables PIM on an interface. |
show ip pim neighbor | Lists the PIM neighbors discovered by the Cisco IOS software. |
To display hardware-switched multicast flow information about IP multicast Multilayer Switching (MLS), use the show mls rp ip multicast EXEC command.
show mls rp ip multicast [locate] [group [source] [vlan-id ]] | [statistics] | [summary]
locate | (Optional) Displays flow information associated with the switch. This keyword applies only to a single router and multiple switches. |
group | (Optional) Address of the IP multicast group about which to display information. |
source | (Optional) IP multicast source sending to the specified multicast group about which to display information. |
vlan-id | (Optional) Source VLAN about which to display information. |
statistics | (Optional) Displays MLS statistics. |
summary | (Optional) Displays MLS summary. |
EXEC
| Release | Modification |
|---|---|
12.0(5)T | This command was introduced. |
The following is sample output of the show mls rp ip multicast command using the locate keyword:
Router# show mls rp ip multicast locate Source Group Vlan SwitchIP SwitchMAC ------ ----- ---- -------- --------- 192.1.10.6 239.255.158.197 10 1.2.10.199 0010.a60b.b4ff
The following is sample output of the show mls rp ip multicast command for a specific IP multicast group:
Router# show mls rp ip multicast 224.1.1.1 Multicast hardware switched flows: (1.1.13.1, 224.1.1.1) Incoming interface: Vlan13, Packets switched: 61590 Hardware switched outgoing interfaces: Vlan20 Vlan9 MFD installed: Vlan13 (1.1.9.3, 224.1.1.1) Incoming interface: Vlan9, Packets switched: 0 Hardware switched outgoing interfaces: Vlan20 MFD installed: Vlan9 (1.1.12.1, 224.1.1.1) Incoming interface: Vlan12, Packets switched: 62010 Hardware switched outgoing interfaces: Vlan20 Vlan9 MFD installed: Vlan12 (1.1.12.3, 224.1.1.1) Incoming interface: Vlan12, Packets switched: 61980 Hardware switched outgoing interfaces: Vlan20 Vlan9 MFD installed: Vlan12 (1.1.11.1, 224.1.1.1) Incoming interface: Vlan11, Packets switched: 62430 Hardware switched outgoing interfaces: Vlan20 Vlan9 MFD installed: Vlan11 (1.1.11.3, 224.1.1.1) Incoming interface: Vlan11, Packets switched: 62430 Hardware switched outgoing interfaces: Vlan20 Vlan9 MFD installed: Vlan11 Total shortcut installed: 6
The following is sample output of the show mls rp ip multicast command using the statistics keyword:
Router# show mls rp ip multicast statistics
MLS Multicast Operation Status:
MLS Multicast configuration and state:
Router Mac: 0010.298f.0009
Switch Mac: 0010.0d70.a3ff Switch IP: 1.2.10.195
MLS Multicast Operating state: ACTIVE
Active management vlan: Vlan1, 192.1.4.1
User configured management vlan: None, 0.0.0.0
Include-List: IP1 = 192.1.28.2, IP2 = 0.0.0.0
Router IP used in MLS Multicast messages: 192.1.28.2
MLS Multicast statistics:
Keepalive sent: 90
Keepalive ACK received: 90
Open request sent: 3
Open request ACK received: 3
Delete notifications received: 3
Flow statistics messages received: 181
Flow message sent: 14
Flow message Ack received: 14
Flow message Nack received: 0
Flow install Ack: 2
Flow install Nack: 0
Flow update Ack: 7
Flow update Nack: 0
Flow delete Ack: 0
Complete flow install Ack: 3
Complete flow install Nack: 0
Complete flow delete Ack: 1
Input vlan delete Ack: 0
Output vlan delete Ack: 0
Global delete sent: 1
L2 entry not found error: 0
LTL entry not found error: 0
MET entry not found error: 0
L3 entry not found error: 0
L3 entry exists error : 0
Hash collision error : 0
Sequence number error : 0
None-supported error : 0
Generic error : 0
The following is sample output of the show mls rp ip multicast command using the summary keyword:
Router# show mls rp ip multicast summary Switch IP:0.0.0.0 Switch MAC:0000.0000.0000 Number of complete flows: 0 Total hardware-switched flows: 0 Switch IP:1.2.10.199 Switch MAC:0010.a60b.b4ff Number of complete flows: 1 Total hardware-switched flows: 1
| Command | Description |
Enables IP multicast MLS. |
This section documents new debug commands. All other commands used with this feature are documented in this feature module or the Cisco IOS Release 12.0 command reference publications.
To display the run-time errors and sequence of events for the multicast distributed switching services (MDSS), use the debug mdss privileged EXEC command. Use the no form of the command to disable debugging output.
[no] debug mdss {all | error | event}
all | Displays both errors and sequence of events for MDSS. |
error | Displays the run-time errors for MDSS. |
event | Displays the run-time sequence of events for MDSS. |
Debugging is not enabled.
| Release | Modification |
|---|---|
12.0(5)T | This command was introduced. |
The following example shows output using the debug mdss command:
Router# debug mdss all mdss all debugging is on Router# clear ip mroute * Router# 01:31:03: MDSS: got MDFS_CLEARALL 01:31:03: MDSS: --> mdss_flush_all_sc 01:31:03: MDSS: enqueue a FE_GLOBAL_DELETE 01:31:03: MDSS: got MDFS_MROUTE_ADD for (0.0.0.0, 224.0.1.40) 01:31:03: MDSS: --> mdss_free_scmdb_cache 01:31:03: MDSS: got MDFS_MROUTE_ADD for (0.0.0.0, 239.255.158.197) 01:31:03: MDSS: got MDFS_MROUTE_ADD for (192.1.21.6, 239.255.158.197) 01:31:03: MDSS: got a MDFS_MIDB_ADD for (192.1.21.6, 239.255.158.197, Vlan21) +Vlan22 01:31:03: MDSS: -- mdss_add_oif 01:31:03: MDSS: enqueue a FE_OIF_ADD (192.1.21.6, 239.255.158.197, Vlan21) +Vlan22 01:31:03: MDSS: mdb (192.1.21.6, 239.255.158.197) fast_flags | MCACHE_MTU 01:31:03: MDSS: got a MDFS_MIDB_ADD for (192.1.21.6, 239.255.158.197, Vlan21) +Vlan23 01:31:03: MDSS: -- mdss_add_oif 01:31:03: MDSS: enqueue a FE_OIF_ADD (192.1.21.6, 239.255.158.197, Vlan21) +Vlan 23 01:31:03: MDSS: mdb (192.1.21.6, 239.255.158.197) fast_flags | MCACHE_MTU 01:31:03: MDSS: got a MDFS_MIDB_ADD for (192.1.21.6, 239.255.158.197, Vlan21) +Vlan24 01:31:03: MDSS: -- mdss_add_oif 01:31:03: MDSS: enqueue a FE_OIF_ADD (192.1.21.6, 239.255.158.197, Vlan21) +Vlan24 01:31:03: MDSS: mdb (192.1.21.6, 239.255.158.197) fast_flags | MCACHE_MTU 01:31:03: MDSS: got a MDFS_MIDB_ADD for (192.1.21.6, 239.255.158.197, Vlan21) +Vlan25 01:31:03: MDSS: -- mdss_add_oif 01:31:03: MDSS: enqueue a FE_OIF_ADD (192.1.21.6, 239.255.158.197, Vlan21) +Vlan25 01:31:03: MDSS: mdb (192.1.21.6, 239.255.158.197) fast_flags | MCACHE_MTU 01:31:03: MDSS: got a MDFS_MIDB_ADD for (192.1.21.6, 239.255.158.197, Vlan21) +Vlan26 01:31:03: MDSS: -- mdss_add_oif 01:31:03: MDSS: enqueue a FE_OIF_ADD (192.1.21.6, 239.255.158.197, Vlan21) +Vlan26 01:31:03: MDSS: mdb (192.1.21.6, 239.255.158.197) fast_flags | MCACHE_MTU 01:31:03: MDSS: got a MDFS_MIDB_ADD for (192.1.21.6, 239.255.158.197,u Vlan21) +Vlan27
| Command | Description |
Displays information relating to Multilayer Switching Protocol (MLSP). |
To display information about Multilayer Switching Protocol (MLSP), use the debug mls rp ip multicast privileged EXEC command. Use the no form of the command to disable debugging output.
[no] debug mls rp ip multicast {all | error | event | packet}
all | Displays all multicast MLSP debugging information, including errors, events, and packets. |
error | Displays error messages related to multicast MLSP. |
event | Displays the run-time sequence of events for multicast MLSP. |
packet | Displays the contents of MLSP packets. |
Debugging is not enabled.
| Release | Modification |
|---|---|
12.0(5)T | This command was introduced. |
One and only one of the keywords is required.
The following example shows output from the debug mls rp ip multicast command using the error keyword:
Router# debug mls rp ip multicast error mlsm error debugging is on chtang-7200# 06:06:45: MLSMERR: scb is INACTIVE, free INSTALL_FE 06:06:46: MLSM: --> mlsm_proc_sc_ins_req(10.0.0.1, 224.2.2.3, 10)
The following example shows output from the debug mls rp ip multicast command using the event keyword:
Router# debug mls rp ip multicast event mlsm events debugging is on Router# 3d23h: MSCP: incoming shortcut flow statistic from Fa2/0.11 3d23h: MLSM: Flow_stat: (192.1.10.6, 239.255.158.197), byte :537792 packet:8403 3d23h: MLSM: byte delta:7680 packet delta:120, time delta: 10 3d23h: MSCP: incoming shortcut flow statistic from Fa2/0.11 3d23h: MLSM: Flow_stat: (192.1.10.6, 239.255.158.197), byte :545472 packet:8523 3d23h: MLSM: byte delta:7680 packet delta:120, time delta: 10 3d23h: MSCP: Router transmits keepalive_msg on Fa2/0.11 3d23h: MSCP: incoming shortcut keepalive ACK from Fa2/0.11 3d23h: MLSM: Include-list: (192.1.2.1 -> 0.0.0.0) 3d23h: MSCP: incoming shortcut flow statistic from Fa2/0.11 3d23h: MLSM: Flow_stat: (192.1.10.6, 239.255.158.197), byte :553152 packet:8643
The following example shows output from the debug mls rp ip multicast command using the packet keyword:
Router# debug mls rp ip multicast packet mlsm packets debugging is on Router# Router# Router# Router# **23h: MSCP(I): 01 00 0c cc cc cc 00 e0 1e 7c fe 5f 00 30 aa aa ...LLL.\Q.|~_.0 ..23h: MSCP(I): 03 00 00 0c 01 07 01 05 00 28 01 02 0a c7 00 10 .........(...G ..23h: MSCP(I): a6 0b b4 ff 00 00 c0 01 0a 06 ef ff 9e c5 00 00 &.4...@...o..E 3d23h: MSCP(I): 00 00 00 09 42 c0 00 00 00 00 00 00 25 0b ....B@......%. 3d23h: **23h: MSCP(O): 01 00 0c 00 00 00 aa 00 04 00 01 04 00 00 aa aa ......*....... LL23h: MSCP(O): 03 00 00 0c 00 16 00 00 00 00 01 00 0c cc cc cc .............L ..23h: MSCP(O): aa 00 04 00 01 04 00 24 aa aa 03 00 00 0c 01 07 *......$**.... ..23h: MSCP(O): 01 06 00 1c c0 01 02 01 aa 00 04 00 01 04 00 00 ....@...*..... 3d23h: MSCP(O): 00 0b 00 00 00 00 00 00 01 01 0a 62 ...........b 3d23h: **23h: MSCP(I): 01 00 0c cc cc cc 00 e0 1e 7c fe 5f 00 24 aa aa ...LLL.\Q.|~_.$ ..23h: MSCP(I): 03 00 00 0c 01 07 01 86 00 1c 01 02 0a c7 00 10 .............G ..23h: MSCP(I): a6 0b b4 ff 00 00 00 0b 00 00 c0 01 02 01 00 00 ..4.......@... 3d23h: MSCP(I): 00 00 3d23h:
| Command | Description |
Displays information about MDSS. |
Posted: Fri Jul 23 17:13:18 PDT 1999
Copyright 1989-1999©Cisco Systems Inc.