多播配置向导

Multicast Configuration Guide

Members should implement the following:

BGP and MBGP to RNO router

PIM sparse mode

local RP (auto RP ?)

MSDP to RNO router

no static mroute

IGMP snooping (or equivalent) on all switches

rate limiting (if/as required)

Notes

CGMP for all-cisco sites. Needs to be enabled on switches and interfaces of routers attached to switches. Low impact on CPU of switch.

IGMP snooping in mixed and/or non-cisco sites. Can have high impact on CPU of switch.

MSDP uses TCP port 639, so check that this is allowed in (to your RP, from your MSDP peers) through firewalls, access lists, etc.

Design Issues

RP - use a loopback address so you can move it around.

RP location - on the border router or nearby/on the core router.

Final Goal - Implementation details

Configuration examples based on Cisco IOS.

Border Router

Enable multicast (use "distributed" mode when using "distributed cef" for less CPU impact/better performance on Cisco 7500 platforms):

ip multicast-routing distributed

Create a multicast boundary on your router interface connected to the RNO router, and set PIM sparse on this boundary:

! create an RNO multicast ACL

! This allows AARNet wide multicast address space to pass,

! and local RNO address space to pass,

! but blocks address space reserved for members private use.

! Use this on all links between an RNO and a members,

! and between members.

ip access-list standard MULTICASTRNOADMIN

remark block Cisco auto-RP

deny 224.0.1.39

deny 224.0.1.40

remark reserved rfc2365

deny 239.0.0.0 0.127.255.255

deny 239.128.0.0 0.63.255.255

remark member only usage

deny 239.224.0.0 0.15.255.255

remark reserved rfc2365

deny 239.253.0.0 0.0.255.255

deny 239.254.0.0 0.0.255.255

deny 239.255.0.0 0.0.255.255

remark allow all remaining multicast

remark including RNO and AARNet scope

permit 224.0.0.0 15.255.255.255

interface gigabitethernet 1/0/0

ip pim bsr-border

ip pim sparse-mode

ip multicast boundary MULTICASTRNOADMIN

Also enable the session directory facility (turn it on on one interface is all that is required):

interface loopback0

ip address A.B.C.D

ip pim sparse-mode

ip sdr listen

Turn on MBGP for your networks (assuming you run BGP, if not make sure the RNO does this on your behalf).

router bgp 65536

network 130.155.0.0 nlri unicast multicast

Enable MBGP to the RNO BGP peer:

router bgp 65536

neighbor 203.15.123.37 remote-as 7570 nlri unicast multicast

Create a local Rendezvous Point (assumes you want to use the loopback mentioned above as the RP address, you might want to create a separate loopback for the RP - which you can move to another router if desired). Specify an access list to stop incorrect multicast sessions from being registered.

ip access-list extended pim-register-filter

deny ip any 224.0.0.0 0.0.0.255

deny ip any 232.0.0.0 0.255.255.255

deny ip 10.0.0.0 0.255.255.255 any

deny ip 127.0.0.0 0.255.255.255 any

deny ip 172.16.0.0 0.15.255.255 any

deny ip 192.168.0.0 0.0.255.255 any

permit ip any any

ip pim rp-address A.B.C.D

ip pim register-rate-limit 2

ip pim accept-register list pim-register-filter

Establish MSDP between local RP and RNO RP

! Create an RNO MSDP filter

! This allows AARNet wide multicast advertisements to pass,

! and allows local RNO advertisements to pass,

　　! but blocks members private advertisements.

　　! Use this on all MSDP peerings between an AARNet RNO and a member,

　　! or between two members.

　　ip access-list extended MSDPRNOFILTER

　　remark SGI-Dogfight

　　deny ip any host 224.0.1.2

　　remark Rwhod

　　deny ip any host 224.0.1.3

　　remark SVRLOC

　　deny ip any host 224.0.1.22

　　remark microsoft-ds

　　deny ip any host 224.0.1.24

　　remark Cisco auto-RP

　　deny ip any host 224.0.1.39

　　deny ip any host 224.0.1.40

　　remark SVRLOC-DA

　　deny ip any host 224.0.1.35

　　remark hp-device-discovery

　　deny ip any host 224.0.1.60

　　remark unknown ...

　　deny ip any host 224.0.2.2

　　remark reserved RFC2365

　　deny ip any 239.0.0.0 0.127.255.255

　　deny ip any 239.128.0.0 0.63.255.255

　　deny ip any 239.253.0.0 0.0.255.255

　　deny ip any 239.254.0.0 0.0.255.255

　　deny ip any 239.255.0.0 0.0.255.255

　　remark member scope multicast

　　deny ip any 239.224.0.0 0.15.255.255

　　remark bad source RFC3330

　　deny ip 127.0.0.0 0.255.255.255 any

　　remark bad source RFC1918

　　deny ip 10.0.0.0 0.255.255.255 any

　　deny ip 172.16.0.0 0.15.255.255 any

　　deny ip 192.168.0.0 0.0.255.255 any

　　remark Source Specific Multicast

　　deny ip any 232.0.0.0 0.255.255.255

　　remark all the rest might be OK

　　remark including RNO and AARNet scope

　　permit ip any any

　　ip msdp peer 203.15.123.37

　　ip msdp description 203.15.123.37 MSDP multicast with NSW RNO

　　ip msdp sa-filter in 203.15.123.37 list MSDPRNOFILTER

　　ip msdp sa-filter out 203.15.123.37 list MSDPRNOFILTER

　　ip msdp cache-sa-state

　　Turn on pim-sparse mode to internal network interfaces.

　　

　　interface FastEthernet2/0

　　ip pim sparse-mode

　　interface FastEthernet3/0

　　ip pim sparse-mode

　　

　　Internal Routers

　　Do the following on all internal routers.

　　

　　Enable multicast (use "distributed" mode when using "distributed cef" for less CPU impact/better performance on Cisco 7500 platforms):

　　

　　ip multicast-routing distributed

　　

　　put pim sparse-mode on all interfaces:

　　

　　interface FastEthernet 1/0

　　ip pim sparse-mode

　　interface FastEthernet 2/0

　　ip pim sparse-mode

　　

　　Also enable the session directory facility (turn it on on one interface is all that is required):

　　

　　interface loopback0

　　ip pim sparse-mode

　　ip sdr listen

　　

　　Specify your RP (using the address mentioned above):

　　

　　ip pim rp-address A.B.C.D

　　

　　Internal Switches

　　Choose one of the following on all internal switches.

　　

　　CGMP

　　Enable CGMP on your switches

　　

　　set cgmp enable

　　

　　Turn on CGMP on router interfaces connected to your switches:

　　

　　interface FastEthernet 1/0

　　ip cgmp

　　interface FastEthernet 2/0

　　ip cgmp

　　

　　IGMP

　　Enable IGMP on your switches

　　

　　set igmp enable

　　

　　Local RP

　　In a large site (many layer 3 routers) you may choose to use auto-RP (Cisco proprietary), or anycast RP, or BSR (but note that BSR does not support scoped addresses properly) to set up your Rendezvous Point. It would also be good to configure a redundant RP.

　　

　　Rate Limiting

　　Rate limiting should be applied on any small link to prevent unwanted flooding of the link by multicast traffic. Care should be paid to shared infrastructure (such as an RNO switch) to ensure the rate limits for all members are the same, and favour the member with the fullest link, otherwise that member will suffer link saturation. On a per-interface basis you can apply the following (units are kilobits per second):

　　

　　interface XYZ0/0

　　ip multicast rate-limit in 600