组播Multicast 5 RP冗余和MSDP

session 1 RP冗余

MSDP：组播源发现协议

       组播源发现协议（MSDP）描述了一种连接多  PIM-SM （PIM-SM ： PIM Sparse Mode） 域的机制。每种 PIM-SM 域都使用自己独立的 RP ，它并不依赖于其它域内的 RP 。也就是组播域间的通信协议，让不同组播域之间的RP建立通信。

 

一、利用MSDP让相同域的多个RP做冗余

       组播域内只能有一个RP，因为每个共享树内都只能有且只有一个RP（逻辑上）。默认情况下spares-mode模式中不同共享树之间的RP不能通信，所以不同共享树之间的源与客户端也就不能通信。所以在同一个共享树中要想有多个RP做冗余就需要使用MSDP让（不同共享树）RP之间相互通信。

       拓扑中组播域内有2个RP，分别为R2与R3的loopback0接口，其中两个RP相互做冗余。在不使用MSDP的情况下，R2-source-recevie1形成一颗共享树，树根为R2，R3-receive2形成一颗共享树，树根为R3。定义了source在R2的共享树上（其实就是始发流量，这里我们ping的始发流量定义为了source），那么这里就有两颗共享树，所以第一个共享树中的源的流量是无法发送到第二课共享树中的recevie2客户端上的。
整体配置如下：

1、底层配置，使用eigrp协议做底层的unicast路由

R1#show run | s eigrp
router eigrp 1
  network 12.1.1.0 0.0.0.255
  network 13.1.1.0 0.0.0.255
  no auto-summary
R1#

 

R2#show run | s eigrp
router eigrp 1
  network 2.2.2.2 0.0.0.0                                                        loop1口ip用作MSDP源地址（后面有）
  network 12.1.1.0 0.0.0.255
  network 13.1.1.0 0.0.0.255
  network 100.1.1.1 0.0.0.0                                               loop0口ip用作RP地址
  network 192.168.1.0
  network 192.168.2.0
  no auto-summary
R2#

 

R3#show run | s eigrp
router eigrp 1
  network 3.3.3.3 0.0.0.0                                                         loop1口ip用作MSDP源地址（后面有）
  network 13.1.1.0 0.0.0.255
  network 100.1.1.1 0.0.0.0                                                 loop0口ip用作RP地址
  network 192.168.3.0
  no auto-summary
R3#

 

source(config)#no ip routing

source(config)#ip default-gateway 192.168.2.1

 

receive1(config)#no ip routing

receive1(config)#ip default-gateway 192.168.1.1

 

receive1(config)#no ip routing

receive1(config)#ip default-gateway 192.168.3.1

 

2、R1、R2、R3启用PIM的spares-mode共享树模式，RP地址为100.1.1.1（R2、R3形成冗余都使用loop0口ip：100.1.1.1作为RP）

R1#show run interface s0/0
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/0
  ip address 12.1.1.1 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R1#

R1#show run interface s0/1
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/1
  ip address 13.1.1.1 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R1#

 

R2#show run interface s0/0
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/0
  ip address 12.1.1.2 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R2#show run interface f0/0
Building configuration...

Current configuration : 116 bytes
!
interface FastEthernet0/0
  ip address 192.168.1.1 255.255.255.0
  ip pim sparse-mode
  duplex auto
  speed auto
end

R2#show run interface f0/1
Building configuration...

Current configuration : 116 bytes
!
interface FastEthernet0/1
  ip address 192.168.2.1 255.255.255.0
  ip pim sparse-mode
  duplex auto
  speed auto
end

R2#

 

R3#show run interface s0/1
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/1
  ip address 13.1.1.3 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R3#show run interface f0/0
Building configuration...

Current configuration : 116 bytes
!
interface FastEthernet0/0
  ip address 192.168.3.1 255.255.255.0
  ip pim sparse-mode
  duplex auto
  speed auto
end

R3#

       使用静态RP指定R2、R3的loopback0接口ip为RP，并且相互形成冗余。R2、R3的loop0接口ip都为100.1.1.1，因为一个组播域内只能指定一个RP地址，至于选择哪个共享树的RP来做根，由R1选择。相当有一个组播域内在没有使用MSDP的冗余RP环境内会让RP形成不同的共享树从而隔离组播流量。

R2#show run interface loopback 0
Building configuration...

Current configuration : 65 bytes
!
interface Loopback0
  ip address 100.1.1.1 255.255.255.255
end

R2(config)# ip pim rp-address 100.1.1.1 

 

R3#show run interface loopback 0
Building configuration...

Current configuration : 65 bytes
!
interface Loopback0
 ip address 100.1.1.1 255.255.255.255
end

R3(config)#ip pim rp-address 100.1.1.1

 

R1#show ip route eigrp
     2.0.0.0/32 is subnetted, 1 subnets
D       2.2.2.2 [90/2297856] via 12.1.1.2, 01:25:32, Serial0/0
     100.0.0.0/32 is subnetted, 1 subnets
D       100.1.1.1 [90/2297856] via 13.1.1.3, 02:42:35, Serial0/1
                         [90/2297856] via 12.1.1.2, 02:42:35, Serial0/0        在R1上已经形成了到达2个RP的负载均衡
     3.0.0.0/32 is subnetted, 1 subnets
D       3.3.3.3 [90/2297856] via 13.1.1.3, 01:25:16, Serial0/1
D    192.168.1.0/24 [90/2195456] via 12.1.1.2, 02:49:13, Serial0/0
D    192.168.2.0/24 [90/2195456] via 12.1.1.2, 02:49:11, Serial0/0
D    192.168.3.0/24 [90/2195456] via 13.1.1.3, 02:49:46, Serial0/1
R1#

这时2颗PIM的spares-mode的共享树已经形成，但是由于2个RP之间没有形成冗余，还是相当于两颗共享树，那么此时source的流量只有同一颗共享树内的receive1可以收到，另外一颗共享树内的receive2不能接收到source的流量的，因为receive2与source不在同一颗共享树内。

source#ping 224.1.1.1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 224.1.1.1, timeout is 2 seconds:

Reply to request 0 from 192.168.1.2, 40 ms              只有receive1可以收到source的组播ping流量

R2#show ip pim rp
Group: 224.1.1.1, RP: 100.1.1.1, uptime 00:18:45, expires never
Group: 224.0.1.40, RP: 100.1.1.1, uptime 00:18:45, expires never
R2#

R3#show ip pim rp
Group: 224.1.1.1, RP: 100.1.1.1, uptime 00:19:09, expires never
Group: 224.0.1.40, RP: 100.1.1.1, uptime 00:19:09, expires never
R3#

source#

R1#show ip pim rp
Group: 224.0.1.40, RP: 100.1.1.1, uptime 00:04:36, expires never
R1#

3、在RP之间使用MSDP协议让不同共享树RP之间冗余
R2(config)#interface loopback 1
R2(config-if)#ip address 2.2.2.2 255.255.255.255

R2(config-if)#exit

R2(config)#ip msdp peer 3.3.3.3 connect-source loopback 1                    使用msdp与R3建立RP对等体，指定使用loopback1接口ip发起tcp连接（类似于BGP的对等体tcp连接）与R3形成RP冗余

R2(config-if)#exit

 

R3(config)#interface loopback 1
R3(config-if)#ip address  3.3.3.3 255.255.255.255

R3(config-if)#exit

R3(config)#ip msdp peer  2.2.2.2 connect-source loopback 1                   使用msdp与R2建立RP对等体，指定使用loopback1接口ip发起tcp连接（如果不用connect-source loopback 1来指定loop1接口的ip来发送tcp的话就需要使用ip msdp originator-id loopback 1来指定tcp发送源接口ip）         

R3(config-if)#exit

 

共享树之间的RP对等体已经建立完成，这时可以让receive2通过对等体RP实现与不同共享树中的source进行组播流量的通信：

source#ping 224.1.1.1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 224.1.1.1, timeout is 2 seconds:

Reply to request 0 from 192.168.3.2, 36 ms                      source已经可以收到receive2的组播流量
Reply to request 0 from 192.168.1.2, 40 ms
source#

 

在R3与R2两个RP都可以看到（S G）表项

R3#show ip mroute
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
             L - Local, P - Pruned, R - RP-bit set, F - Register flag,
             T - SPT-bit set, J - Join SPT, M - MSDP created entry,
             X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,
             U - URD, I - Received Source Specific Host Report,
             Z - Multicast Tunnel, z - MDT-data group sender,
             Y - Joined MDT-data group, y - Sending to MDT-data group
Outgoing interface flags: H - Hardware switched, A - Assert winner
  Timers: Uptime/Expires
  Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 224.1.1.1), 04:15:34/stopped, RP 100.1.1.1, flags: SJC
   Incoming interface: Null, RPF nbr 0.0.0.0
   Outgoing interface list:
       FastEthernet0/0, Forward/Sparse, 04:15:34/00:02:31

(192.168.2.2, 224.1.1.1), 00:00:59/00:02:00, flags: M
  Incoming interface: Serial0/1, RPF nbr 13.1.1.1
  Outgoing interface list:
    FastEthernet0/0, Forward/Sparse, 00:00:59/00:02:31

(*, 224.0.1.40), 01:36:34/00:02:50, RP 100.1.1.1, flags: SJCL
   Incoming interface: Null, RPF nbr 0.0.0.0
   Outgoing interface list:
       Serial0/1, Forward/Sparse, 00:56:27/00:02:50

R3#

 

R2#show ip mroute
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
             L - Local, P - Pruned, R - RP-bit set, F - Register flag,
             T - SPT-bit set, J - Join SPT, M - MSDP created entry,
             X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,
             U - URD, I - Received Source Specific Host Report,
             Z - Multicast Tunnel, z - MDT-data group sender,
             Y - Joined MDT-data group, y - Sending to MDT-data group
Outgoing interface flags: H - Hardware switched, A - Assert winner
  Timers: Uptime/Expires
  Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 224.1.1.1), 04:16:36/stopped, RP 100.1.1.1, flags: SJC
   Incoming interface: Null, RPF nbr 0.0.0.0
   Outgoing interface list:
       FastEthernet0/0, Forward/Sparse, 04:16:21/00:02:57

(192.168.2.2, 224.1.1.1), 00:01:34/00:02:05, flags: TA
  Incoming interface: FastEthernet0/1, RPF nbr 0.0.0.0
  Outgoing interface list:
    Serial0/0, Forward/Sparse, 00:01:34/00:02:55
    FastEthernet0/0, Forward/Sparse, 00:01:36/00:02:55

(*, 224.0.1.40), 01:37:19/stopped, RP 100.1.1.1, flags: SJCL
   Incoming interface: Null, RPF nbr 0.0.0.0
   Outgoing interface list:
       Serial0/0, Forward/Sparse, 00:57:22/00:00:09

R2#

 

冗余检测：R2上将RP接口down，再看source是否能和receive2组播通信

R2#show run interface loopback 0
Building configuration...

Current configuration : 75 bytes
!
interface Loopback0
 ip address 100.1.1.1 255.255.255.255
 shutdown
end

R2#

 

R1#show ip route eigrp
     2.0.0.0/32 is subnetted, 1 subnets
D       2.2.2.2 [90/2297856] via 12.1.1.2, 03:05:22, Serial0/0
     100.0.0.0/32 is subnetted, 1 subnets
D       100.1.1.1 [90/2297856] via 13.1.1.3, 00:06:00, Serial0/1              R2的loopback0已经被shutdown，R1上已经没有去往R2的loopback0的路由了，只有通过13.1.1.3去往R3的loop0的路由了
     3.0.0.0/32 is subnetted, 1 subnets
D       3.3.3.3 [90/2297856] via 13.1.1.3, 03:05:06, Serial0/1
D    192.168.1.0/24 [90/2195456] via 12.1.1.2, 04:29:03, Serial0/0
D    192.168.2.0/24 [90/2195456] via 12.1.1.2, 04:29:01, Serial0/0
D    192.168.3.0/24 [90/2195456] via 13.1.1.3, 04:29:36, Serial0/1
R1#

 

R2#show ip mroute
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
       L - Local, P - Pruned, R - RP-bit set, F - Register flag,
       T - SPT-bit set, J - Join SPT, M - MSDP created entry,
       X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,
       U - URD, I - Received Source Specific Host Report,
       Z - Multicast Tunnel, z - MDT-data group sender,
       Y - Joined MDT-data group, y - Sending to MDT-data group
Outgoing interface flags: H - Hardware switched, A - Assert winner
 Timers: Uptime/Expires
 Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 224.0.1.40), 00:00:02/00:02:57, RP 100.1.1.1, flags: SJPCL
  Incoming interface: Serial0/0, RPF nbr 12.1.1.1
  Outgoing interface list: Null

R2#

R2的组播路由表也清空，现在用source发组播ping到224.1.1.1检测receive2是否可以回应组播流量

source#ping 224.1.1.1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 224.1.1.1, timeout is 2 seconds:

Reply to request 0 from 192.168.3.2, 24 ms                       依然可以收到receive2的组播回应，形成RP冗余
Reply to request 0 from 192.168.1.2, 28 ms
source#

 

R2#show ip mroute
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
       L - Local, P - Pruned, R - RP-bit set, F - Register flag,
       T - SPT-bit set, J - Join SPT, M - MSDP created entry,
       X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,
       U - URD, I - Received Source Specific Host Report,
       Z - Multicast Tunnel, z - MDT-data group sender,
       Y - Joined MDT-data group, y - Sending to MDT-data group
Outgoing interface flags: H - Hardware switched, A - Assert winner
 Timers: Uptime/Expires
 Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 224.1.1.1), 00:01:09/stopped, RP 100.1.1.1, flags: SJCF
  Incoming interface: Serial0/0, RPF nbr 12.1.1.1
  Outgoing interface list:
    FastEthernet0/0, Forward/Sparse, 00:01:09/00:02:20

(192.168.2.2, 224.1.1.1), 00:01:09/00:03:21, flags: FT
  Incoming interface: FastEthernet0/1, RPF nbr 0.0.0.0, Registering
  Outgoing interface list:
    Serial0/0, Forward/Sparse, 00:01:09/00:03:17, A
    FastEthernet0/0, Forward/Sparse, 00:01:10/00:02:18

(*, 224.0.1.40), 00:01:15/00:01:44, RP 100.1.1.1, flags: SJPCL
  Incoming interface: Serial0/0, RPF nbr 12.1.1.1
  Outgoing interface list: Null

R2#

 

session 2 使用MSDP协议实现域间组播

MSDP：组播源发现协议

       组播源发现协议（MSDP）描述了一种连接多  PIM-SM （PIM-SM ： PIM Sparse Mode） 域的机制。每种 PIM-SM 域都使用自己独立的 RP ，它并不依赖于其它域内的 RP 。也就是组播域间的通信协议，让不同组播域之间的RP建立通信。

在两个BGPAS之间通过MSDP实现组播流量的传递。

  左边BGP区域AS为123，右边BGP区域AS为456，两边组播pim的RP分别是R2与R5，通过MSDP让source与receive组播通信。

  配置如下：

source#show run int s0/0
Building configuration...

Current configuration : 134 bytes
!
interface Serial0/0
  ip address 192.168.1.2 255.255.255.0
  no ip route-cache
  ip igmp join-group 224.1.1.1
  clock rate 2000000
end

source#

source(config)#no ip routing
source(config)#ip default-gateway 192.168.1.1

 

 

R2-RP1#show run int s0/0
Building configuration...

Current configuration : 105 bytes
!
interface Serial0/0
  ip address 192.168.1.1 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R2-RP1#show run int s0/1
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/1
  ip address 23.1.1.2 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R2-RP1#show run interface lo0
Building configuration...

Current configuration : 63 bytes
!
interface Loopback0
 ip address 2.2.2.2 255.255.255.255
end

R2-RP1#
R2-RP1#show run | s bgp 
router bgp 123
 no synchronization
 bgp log-neighbor-changes
 network 2.2.2.2 mask 255.255.255.255
 network 23.1.1.0 mask 255.255.255.0
 network 192.168.1.0
 neighbor 23.1.1.3 remote-as 123
 no auto-summary
R2-RP1#

R2-RP1(config)#ip pim rp-address 2.2.2.2
R2-RP1(config)#ip msdp peer 5.5.5.5 connect-source Loopback0

 

R3#show run int s0/1
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/1
  ip address 23.1.1.3 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R3#show run int s0/2
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/2
  ip address 34.1.1.3 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R3#

R3#show run | s bgp
router bgp 123
  no synchronization
  bgp log-neighbor-changes
  network 23.1.1.0 mask 255.255.255.0
  network 34.1.1.0 mask 255.255.255.0
  neighbor 23.1.1.2 remote-as 123
  neighbor 34.1.1.4 remote-as 456
  no auto-summary
R3#

 

R4#show run int s0/2
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/2
  ip address 34.1.1.4 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R4#show run int s0/0
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/0
  ip address 45.1.1.4 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R4#

R4#show run | s bgp
router bgp 456
  no synchronization
  bgp log-neighbor-changes
  network 34.1.1.0 mask 255.255.255.0
  network 45.1.1.0 mask 255.255.255.0
  neighbor 34.1.1.3 remote-as 123
  neighbor 45.1.1.5 remote-as 456
  no auto-summary
R4#

 

R5-RP2#show run interface s0/0
Building configuration...

Current configuration : 102 bytes
!
interface Serial0/0
  ip address 45.1.1.5 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R5-RP2#show run interface s0/1
Building configuration...

Current configuration : 104 bytes
!
interface Serial0/1
  ip address 172.16.1.1 255.255.255.0
  ip pim sparse-mode
  clock rate 2000000
end

R5-RP2#show run interface lo0
Building configuration...

Current configuration : 63 bytes
!
interface Loopback0
  ip address 5.5.5.5 255.255.255.255
end

R5-RP2#

R5-RP2#show run | s bgp
router bgp 456
  no synchronization
  bgp log-neighbor-changes
  network 5.5.5.5 mask 255.255.255.255
  network 45.1.1.0 mask 255.255.255.0
  network 172.16.1.0 mask 255.255.255.0
  neighbor 45.1.1.4 remote-as 456
  no auto-summary
R5-RP2#

R5-RP2(config)#ip pim rp-address 5.5.5.5

R5-RP2(config)#ip msdp peer 2.2.2.2 connect-source loopback 0

 

  receive#show run interface s0/1
Building configuration...

Current configuration : 133 bytes
!
interface Serial0/1
  ip address 172.16.1.2 255.255.255.0
  no ip route-cache
  ip igmp join-group 224.1.1.1
  clock rate 2000000
end

receive#

 

source#ping 224.1.1.1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 224.1.1.1, timeout is 2 seconds:

Reply to request 0 from 172.16.1.2, 12 ms
source#

 

R5-RP2#show ip mroute
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
             L - Local, P - Pruned, R - RP-bit set, F - Register flag,
             T - SPT-bit set, J - Join SPT, M - MSDP created entry,
             X - Proxy Join Timer Running, A - Candidate for  MSDP Advertisement,
             U - URD, I - Received Source Specific Host Report,
             Z - Multicast Tunnel, z - MDT-data group sender,
             Y - Joined MDT-data group, y - Sending to MDT-data group
Outgoing interface flags: H - Hardware switched, A - Assert winner
  Timers: Uptime/Expires
  Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 224.1.1.1), 09:22:38/stopped, RP 5.5.5.5, flags: SJC
   Incoming interface: Null, RPF nbr 0.0.0.0
   Outgoing interface list:
       Serial0/1, Forward/Sparse, 09:22:38/00:02:10

(192.168.1.2, 224.1.1.1), 00:00:55/00:02:04, flags:  M
   Incoming interface: Serial0/0, RPF nbr 45.1.1.4
   Outgoing interface list:
       Serial0/1, Forward/Sparse, 00:00:55/00:02:10

(*, 224.0.1.40), 09:22:46/00:02:33, RP 5.5.5.5, flags: SJCL
   Incoming interface: Null, RPF nbr 0.0.0.0
   Outgoing interface list:
       Serial0/0, Forward/Sparse, 09:22:46/00:02:33

R5-RP2#