Configuring IPv6 Multicast PFC3 and DFC3 Layer 3 Switching

The PFC3 and DFC3 provide hardware support for IPv6 multicast traffic. Use these publications to configure IPv6 multicast on Cisco 7600 series routers:

  • The Cisco IOS IPv6 Configuration Library, “Implementing IPv6 Multicast”:

http://www.cisco.com/en/US/docs/ios/ipv6/configuration/guide/ip6-multicast.html

  • The Cisco IOS IPv6 Command Reference :

http://www.cisco.com/en/US/docs/ios/ipv6/command/reference/ipv6_book.html

These sections provide additional information about IPv6 multicast support on Cisco 7600 series routers:

Features that Support IPv6 Multicast

These features support IPv6 multicast:


Note MLDv1 snooping is not supported.


http://www.cisco.com/en/US/docs/ios/12_2t/ipv6/ipv6_vgf.html

  • SSM mapping for IPv6—See this publication:

http://www.cisco.com/en/US/docs/ios/12_2t/ipv6/ipv6_vgf.html

IPv6 Multicast Guidelines and Restrictions

These guidelines and restrictions apply to IPv6 multicast support on Cisco 7600 series routers:

  • The PFC3 and DFC3 provide hardware support for the following:

Completely switched IPv6 multicast flows

IPv6 PIM-Sparse Mode (PIM-SM) (S,G) forwarding

Multicast RPF check for IPv6 PIM-SM (S,G) traffic using the NetFlow table

Rate limiting of IPv6 PIM-SM (S,G) traffic that fails the multicast RPF check

Static IPv6 multicast routes

SSM Mapping for IPv6 (PIM-SSM)

IPv6 multicast forwarding information base (MFIB) using the NetFlow table

IPv6 distributed MFIB (dMFIB) using the NetFlow table

Link-local and link-global IPv6 multicast scopes

Egress multicast replication with the ipv6 mfib hardware-switching command

Ingress interface statistics for multicast routes (egress interface statistics not available)

RPR and RPR+ redundancy mode (see Chapter 7, “Configuring RPR and RPR+ Supervisor Engine Redundancy”)

Ingress and egress PFC QoS (see Chapter 48, “Configuring PFC QoS”)

Input and output Cisco access-control lists (ACLs)

  • The PFC3 and DFC3 do not provide hardware support for the following:

Partially switched IPv6 multicast flows

PIM-SM (*,G) forwarding

Multicast RPF check for PIM-SM (*,G) traffic

Multicast helper maps

Site-local multicast scopes

Manually configured IPv6 over IPv4 tunnels

IPv6 multicast 6to4 tunnels

IPv6 multicast automatic tunnels

IPv6 over GRE tunnels

IPv6-in-IPv6 PIM register tunnels

IPv6 multicast basic ISATAP tunnels

ISATAP tunnels with embedded 6to4 tunnels

Configuring IPv6 Multicast Layer 3 Switching

To configure IPv6 multicast Layer 3 switching, perform this task:

 

Command
Purpose

Step 1

Router(config)# ipv6 unicast-routing

Enables unicast routing on all Layer 3 interfaces.

Step 2

Router(config)# ipv6 multicast-routing

Enables PIM-SM on all Layer 3 interfaces.

Using show Commands to Verify IPv6 Multicast Layer 3 Switching

These sections describe how to use show commands to verify IPv6 multicast Layer 3 switching:


Note The show commands in the following sections are for a router with a DFC3-equipped switching module in slot 1 and a Supervisor Engine 720 with a PFC3 in slot 6.


Verifying MFIB Clients

This example shows the complete output of the show ipv6 mrib client command:

Router# show ipv6 mrib client
IP MRIB client-connections
mfib ipv6:81 (connection id 0)
igmp:124 (connection id 1)
pim:281 (connection id 2)
slot 1 mfib ipv6 rp agent:15 (connection id 3)
slot 6 mfib ipv6 rp agent:15 (connection id 4)
 

This example shows how to display the MFIB client running on the MSFC:

Router# show ipv6 mrib client | include ^mfib ipv6
mfib ipv6:81 (connection id 0)
 

This example shows how to display the MFIB clients running on the PFC3 and any DFC3s:

Router# show ipv6 mrib client | include slot
slot 1 mfib ipv6 rp agent:15 (connection id 3)
slot 6 mfib ipv6 rp agent:15 (connection id 4)

Displaying the Switching Capability

This example displays the complete output of the show platform software multicast ipv6 capability command:

Router# show platform software multicast ipv6 capability | i switching
Hardware switching for IPv6 is enabled
(S,G) forwarding for IPv6 supported using Netflow
(*,G) bridging for IPv6 is supported using FIB
Directly-connected entries for IPv6 is supported using ACL-TCAM.
 
Current System HW Replication Mode : Egress
Auto-detection of Replication Mode : ON
 
Slot Replication-Capability Replication-Mode
2 Egress Egress
3 Egress Egress
4 Egress Egress
6 Egress Egress
 
PE1-7600#

Verifying the (S,G) Forwarding Capability

This example shows how to verify the (S,G) forwarding:

Router# show platform software ipv6-multicast capability | include (S,G)
(S,G) forwarding for IPv6 supported using Netflow

Verifying the (*,G) Forwarding Capability

This example shows how to verify the (*,G) forwarding:

Router# show platform software ipv6-multicast capability | include (\*,G)
(*,G) bridging for IPv6 is supported using FIB

Verifying the Subnet Entry Support Status

This example shows how to verify the subnet entry support status:

Router# show platform software ipv6-multicast capability | include entries
Directly-connected entries for IPv6 is supported using ACL-TCAM.

Displaying the Replication Mode Capabilities

This example shows how to display the replication mode capabilities of the installed modules:

Router# show platform software multicast ipv6 capability
Hardware switching for IPv6 is enabled
(S,G) forwarding for IPv6 supported using Netflow
(*,G) bridging for IPv6 is supported using FIB
Directly-connected entries for IPv6 is supported using ACL-TCAM.
 
Current System HW Replication Mode : Egress
Auto-detection of Replication Mode : ON
 
Slot Replication-Capability Replication-Mode
2 Egress Egress
3 Egress Egress
4 Egress Egress
6 Egress Egress

Displaying Subnet Entries

This example shows how to display subnet entries:

Router# show platform software multicast ipv6 connected
IPv6 Multicast Subnet entries
Flags : H - Installed in ACL-TCAM
X - Not installed in ACL-TCAM due to
label-full exception

Displaying the IPv6 Multicast Summary

This example shows how to display the IPv6 multicast summary:

Router# show platform software multicast ipv6 summary module 4
IPv6 Multicast Netflow SC summary on Slot[4]:
Shortcut Type Shortcut count
---------------------------+--------------
(S, G) 0
(*, G) 0
 
IPv6 Multicast FIB SC summary on Slot[4]:
Shortcut Type Shortcut count
---------------------------+--------------
(*, G/128) 0
(*, G/m) 3

Displaying the NetFlow Hardware Forwarding Count

This example shows how to display the NetFlow hardware forwarding count:

Router# show platform software ipv6-multicast summary
IPv6 Multicast Netflow SC summary on Slot[1]:
Shortcut Type Shortcut count
---------------------------+--------------
(S, G) 100
(*, G) 0
 
<...Output deleted...>
 
IPv6 Multicast Netflow SC summary on Slot[6]:
Shortcut Type Shortcut count
---------------------------+--------------
(S, G) 100
(*, G) 0
<...Output truncated...>
 

Note The Netflow (*, G) count is always zero because PIM-SM (*,G) forwarding is supported in software on the MSFC3.


Displaying the FIB Hardware Bridging and Drop Counts

This example shows how to display the FIB hardware bridging and drop hardware counts:

Router# show platform software ipv6-multicast summary | begin FIB
IPv6 Multicast FIB SC summary on Slot[1]:
Shortcut Type Shortcut count
---------------------------+--------------
(*, G/128) 10
(*, G/m) 47
 
<...Output deleted...>
 
IPv6 Multicast FIB SC summary on Slot[6]:
Shortcut Type Shortcut count
---------------------------+--------------
(*, G/128) 10
(*, G/m) 47
 

Note The (*, G/128) value is a hardware bridge entry count.

  • The (*, G/m) value is a hardware bridge/drop entry count.


 

Displaying the Shared and Well-Known Hardware Adjacency Counters

The show platform software multicast ipv6 shared-adjacencies command displays the shared and well-known hardware adjacency counters used for IPv6 multicast by entries in FIB and ACL-TCAM.

Router# show platform software multicast ipv6 shared-adjacencies module 4
 
---- SLOT [4] ----
 
Shared IPv6 Mcast Adjacencies Index Packets Bytes
----------------------------- ------ ------------- ------------------
Subnet bridge adjacency 0x7F802 0 0
Control bridge adjacency 0x7 0 0
StarG_M bridge adjacency 0x8 0 0
S_G bridge adjacency 0x9 0 0
Default drop adjacency 0xA 0 0
StarG (spt == INF) adjacency 0xB 0 0
StarG (spt != INF) adjacency 0xC 0 0
 
---- SLOT [6] ----
 
Shared IPv6 Mcast Adjacencies Index Packets Bytes
----------------------------- ------ ------------- ------------------
Subnet bridge adjacency 0x7F802 0 0
Control bridge adjacency 0x7 0 0
StarG_M bridge adjacency 0x8 0 0
S_G bridge adjacency 0x9 0 0
Default drop adjacency 0xA 0 0
StarG (spt == INF) adjacency 0xB 0 0
StarG (spt != INF) adjacency 0xC 0 0
Router