- Read Me First
- IP Multicast Technology Overview
- Configuring Basic IP Multicast
- Configuring Basic IP Multicast in IPv6 Networks
- Using MSDP to Interconnect Multiple PIM-SM Domains
- PIM Allow RP
- Configuring Source Specific Multicast
- Tunneling to Connect Non-IP Multicast Areas
- Automatic Multicast Tunneling
- BFD Support for Multicast (PIM)
- HSRP Aware PIM
- VRRP Aware PIM
- Verifying IP Multicast Operation
- Monitoring and Maintaining IP Multicast
- Multicast User Authentication and Profile Support
- IPv6 Multicast: Bootstrap Router
- IPv6 Multicast: PIM Sparse Mode
- IPv6 Multicast: Static Multicast Routing for IPv6
- IPv6 Multicast: PIM Source-Specific Multicast
- IPv6 Source Specific Multicast Mapping
- IPv6 Multicast: Explicit Tracking of Receivers
- IPv6 Bidirectional PIM
- IPv6 PIM Passive Mode
- IPv6 Multicast: Routable Address Hello Option
- PIMv6 Anycast RP Solution
- MTR in VRF
- Finding Feature Information
- Restrictions for Automatic Multicast Tunneling
- Overview
- Advantages of Automatic Multicast Tunneling
- Prerequisites for AMT
- Configuration Recommendations for AMT
- Enabling and Configuring Automatic Multicast Tunneling on a Relay
- Enabling and Configuring Automatic Multicast Tunneling on Gateway
- Displaying and Verifying AMT Configuration
- Displaying and Verifying AMT Relay Configuration
- Displaying and Verifying AMT Gateway Configuration
- Example: AMT Relay Configuration
- Example: AMT Gateway Configuration
- Additional References for Automatic Multicast Tunneling
- Feature Information for Automatic Multicast Tunneling
Automatic
Multicast Tunneling
Automatic Multicast Tunneling (AMT) provides a method to tunnel multicast data over a unicast network. The tunneling is performed between AMT relays and AMT gateways, using User Datagram Protocol (UDP) encapsulation. AMT enables service providers and their customers to participate in delivering multicast traffic even in the absence of end-to-end multicast connectivity.
- Finding Feature Information
- Restrictions for Automatic Multicast Tunneling
- Additional References for Automatic Multicast Tunneling
- Feature Information for Automatic Multicast Tunneling
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Restrictions for Automatic Multicast Tunneling
Overview
The multicast source sends traffic to the first-hop. Multicast traffic flows through the network until it reaches the last-hop (receivers) or AMT relays. AMT Relay is a multicast router configured to support transit routing between nonmulticast capable internetwork and the native multicast infrastructure.
The following diagram provides a sample AMT network where Relay1 and Relay2 are two AMT relays, which encapsulate the traffic into AMT tunnels, and send one copy to each of the AMT gateways.
Automatic Multicast Tunneling Message Exchanges
The AMT protocol defines seven message types for control and encapsulation. The message exchanges happen in the following sequence:
-
Relay Discovery—Gateway sends an AMT discovery message to an anycast address that represents the AMT relay.
-
Relay Advertisement—Relay responds with an advertisement message, which includes the relay’s unique IP address.
-
Relay Request—Gateway sends an AMT Request message to the relay using the unique IP address as the destination, along with a nonce to be used for security.
-
Membership Query—Relay responds with an AMT query that includes the nonce from the AMT request and an opaque security code.
-
Membership Update—Gateway responds with a membership update that includes an encapsulated IGMPv3/MLDv2 packet.
-
Teardown—Gateway sends a message to stop the delivery of multicast data messages requested in an earlier membership update message.
-
After validation the Relay establishes the AMT Tunnel and starts sending multicast traffic [Type 6]. Any further (S,G) uses the same Request/Query/Update - three-way handshake because the tunnel is already established.
AMT Tunnel and Traffic Types
The multicast traffic carried in the AMT tunnel may be IPv4 or IPv6. The AMT tunnel may be setup with IPv4 or IPv6 endpoints, thereby providing the following possibilities.
-
IPv4-in-IPv4—IPv4 multicast traffic carried over an IPv4 tunnel
-
IPv6-in-IPv4—IPv6 multicast traffic carried over an IPv4 tunnel
-
IPv6-in-IPv6—IPv6 multicast traffic carried over an IPv6 tunnel
-
IPv4-in-IPv6—IPv4 multicast traffic carried over an IPv6 tunnel
Note | In Cisco IOS XE Release 3.15S, AMT supports IPv4-in-IPv4 and IPv6-in-IPv4 only. |
Advantages of Automatic Multicast Tunneling
-
Simplicity—Instead of incurring the overhead of manually provisioning, establishing and maintaining GRE tunnels between two locations, the receiving network simply sends AMT advertisements to a well-known any-cast prefix. The rest of the tunnel establishment process is done automatically without the need for additional configuration.
-
Resiliency—Because the relay discovery uses an any-cast address, gateways automatically find the closest relay. If that relay becomes unavailable or unreachable, the routing table reconverges on the next closest relay.
-
Efficiency—AMT allows transit routers to perform flow-based load balancing for more efficient link utilization.
Automatic Multicast Tunneling supports IPv4 transport for tunnel and also support for IPv4 multicast traffic & IPv6 multicast traffic. You can also configure AMT relay-only, gateway-only and relay-gateway coexisting modes.
Prerequisites for AMT
-
AMT relay and gateway tunnel requires an interface IP address. However the interface IP addresses do not need to be unique. You can configure the same addresses for the tunnel source address using the ip unnumbered command.
-
You must configure IGMP version 3 on the tunnel interfaces for the SSM to work across tunnels.
-
The tunnel source port and tunnel destination port must be configured to achieve a valid AMT configuration.
Configuration Recommendations for AMT
The tunnel source interface address should be an interface that is set up to be reachable from receivers under all instances. You can use a physical interface address, but it can cause the tunnel to go down if that physical interface is down. A loopback interface is recommended to sustain availability. You do not need a separate loopback address, you can reuse the loopback interface that you usually would have to carry router and router-ID IP address (usually Loopback 0).
IP PIM passive is the recommended and supported mode on AMT interfaces to enable IP multicast routing for AMT tunnel interfaces. This is recommended since no PIM messages (only AMT/IGMP messages) will be sent or received via the AMT tunnel.
On an AMT relay, you need only one tunnel interface to which all gateways can connect. Therefore the interface is a multipoint interface. Every gateway interface can only connect to one relay, but you can configure multiple tunnel interfaces.
Even though AMT tunnels (relay and gateway) only support IPv4 tunnels, the IPv4 tunnels can carry both IPv4 and IPv6 simultaneously. You can configure the AMT for the version(s) of IP that you need.
If you want to set up a redundant AMT relay, your AMT relay address configured on the gateway should be any IP address that you set up as an anycast address on your relays. If you do not plan to use redundant (Anycast) Relay, you can use the relays tunnel source address on the gateways.
If you shut down the anycast Loopback interface, the AMT relay would not accept new AMT gateway tunnel requests. IP routing for the anycast address would only point to any other relays active with the same address and new requests would therefore go to those relays. Any AMT gateways already connected to this relay would stay on this relay, because they already are using the relays interface address.
Enabling and Configuring Automatic Multicast Tunneling on a Relay
Note | Switch-over from active relay to backup relay can take more than 5 minutes. |
1.
enable
2.
configure terminal
3.
interface tunnel
number
4.
ip address
ip-address
mask
5.
no ip redirects
6.
ip pim sparse-mode
7.
ip igmp version
version
number
8.
ipv6 enable
9.
tunnel source
interface-type
interface-number
10.
tunnel mode udp multipoint
11.
tunnel dst-port dynamic
12.
tunnel src-port dynamic
13.
amt relay traffic {ip |
ipv6}
14.
exit
15.
ip multicast-routing
distributed
16.
ipv6
multicast-routing
17.
ip pim ssm {default
|
range
access-list}
DETAILED STEPS
Enabling and Configuring Automatic Multicast Tunneling on Gateway
1.
enable
2.
configure terminal
3.
interface tunnel
number
4.
ip address
ip-address
mask
5.
ip pim passive
6.
ip igmp version
version
number
7.
ipv6 enable
8.
ipv6 pim passive
9.
tunnel source
interface-type
interface-number
10.
tunnel mode udp ip
11.
tunnel destination dynamic
12.
tunnel dst-port dynamic
13.
tunnel src-port dynamic
14.
amt gateway traffic
{ip |
ipv6}
15.
amt gateway
relay-address
IP
address
16.
exit
17.
ip multicast-routing
distributed
18.
ipv6
multicast-routing
19.
ip pim ssm {default
|
range
access-list}
20.
ipv6 multicast
pim-passive-enable
21.
ip route
ip-address
interface-type interface-number [multicast]
22.
ipv6 route
ipv6-prefix/prefix-length
interface-type interface-number
[multicast]
DETAILED STEPS
Displaying and Verifying AMT Configuration
1.
ping
3.3.3.3
source
5.5.5.5
2.
show ip igmp membership
3.
show ip mroute
4.
show ip rpf10.3.3.1
DETAILED STEPS
Displaying and Verifying AMT Relay Configuration
1.
enable
2.
show ip amt
tunnel
3.
show ip mroute
section [group-address]
4.
show ipv6 mroute
section [group-address]
5.
show ip mfib section
[group-address]
6.
show ipv6 mfib
section [group-address]
7.
show platform software ip
rp active mfib section [group-address]
8.
show platform software ipv6
rp active mfib section [group-address]
9.
show platform software
mlist rp active index
multicast-index-number
10.
show platform software
adjacency rp active index
platform-allocated-index-value
11.
show ip interface brief
DETAILED STEPS
Step 1 |
enable
Example: Device> enable Enables privileged EXEC mode. |
Step 2 |
show ip amt
tunnel
Example: Device# show ip amt tunnel AMT Relay tunnel: Local address UDP port 11.11.11.11 2268 (0x8DC ) Remote address Expire time 33.33.33.33 59464(0xE848) 00:03:07 Connected to 1 Gateway Total active Gateways: 1Displays AMT relay configuration. |
Step 3 |
show ip mroute
section [group-address]
Example: Device# show ip mroute section 232.1.1.1 (101.0.0.2, 232.1.1.1), 2d00h/00:02:18, flags: sTI Incoming interface: GigabitEthernet0/0/4, RPF nbr 0.0.0.0 Outgoing interface list: Tunnel10, 33.33.33.33, UDP port 59464, Forward/Sparse, 2d00h/00:02:18Displays information about sparse mode routes in the IP multicast routing (mroute) table for the specified multicast group. |
Step 4 |
show ipv6 mroute
section [group-address]
Example: Device# show ipv6 mroute section 232.1.1.1 (2011::101:0:0:2, FF3F::232:1:1:1), 2d00h/never, flags: sTI Incoming interface: GigabitEthernet0/0/4 RPF nbr: 2011::101:0:0:2 Immediate Outgoing interface list: Tunnel10, AMT NH 33.33.33.33, UDP Port 59464, Forward, 2d00h/neverDisplays information about sparse mode routes in the IPv6 mroute table for the specified multicast group. |
Step 5 |
show ip mfib section
[group-address]
Example: Device# show ip mfib section 232.1.1.1 (101.0.0.2,232.1.1.1) Flags: HW SW Forwarding: 0/0/0/0, Other: 0/0/0 HW Forwarding: NA/NA/NA/NA, Other: NA/NA/NA GigabitEthernet0/0/4 Flags: A Tunnel10, AMT Encap 33.33.33.33, UDP Port:59464 Flags: F NS Pkts: 0/0Displays the status of entries and interfaces in the IPv4 Multicast Forwarding Information Base (MFIB) for the specified multicast group. |
Step 6 |
show ipv6 mfib
section [group-address]
Example: Device# show ipv6 mfib section 232.1.1.1 (2011::101:0:0:2,FF3F::232:1:1:1) Flags: HW SW Forwarding: 0/0/0/0, Other: 0/0/0 HW Forwarding: NA/NA/NA/NA, Other: NA/NA/NA GigabitEthernet0/0/4 Flags: A Tunnel10, AMT Encap 33.33.33.33, UDP Port:59464 Flags: F NS Pkts: 0/0Displays the status of entries and interfaces in the IPv6 Multicast Forwarding Information Base (MFIB) for the specified multicast group. |
Step 7 |
show platform software ip
rp active mfib section [group-address]
Example: Device# show platform software ip rp active mfib section 232.1.1.1 232.1.1.1, 101.0.0.2/64 --> OBJ_INTF_LIST (0x5a) Obj id: 0x5a, Flags: OM handle: 0x421712c4Displays platform software IPv4 MFIB route processor information for the specified multicast group. |
Step 8 |
show platform software ipv6
rp active mfib section [group-address]
Example: Device# show platform software ipv6 rp active mfib section 232.1.1.1 ff3f::232:1:1:1, 2011::101:0:0:2/256 --> OBJ_INTF_LIST (0x5b) Obj id: 0x5b, Flags: OM handle: 0x42171d24Displays platform software IPv6 MFIB route processor information for the specified multicast group. |
Step 9 |
show platform software
mlist rp active index
multicast-index-number
Example: Device# show platform software mlist rp active index 0x5a OCE Type OCE Flags Interface -------------------------------------------------------------------------------------- 0x57 OBJ_ADJACENCY NS, F Tunnel10 0xf80000c1 OBJ_ADJACENCY A GigabitEthernet0/0/4Displays platform software route processor information for the specified multicast list index. |
Step 10 |
show platform software
adjacency rp active index
platform-allocated-index-value
Example: Device# show platform software adjacency rp active index 0x57 Number of adjacency objects: 22 Adjacency id: 0x57 (87) Interface: Tunnel10, IF index: 20, Link Type: MCP_LINK_IP Encap: 45:0:0:0:0:0:0:0:ff:11:63:95:b:b:b:b:21:21:21:21:8:dc:e8:48:0:0:0:0:6:0 Encap Length: 30, Encap Type: MCP_ET_TUNNEL, MTU: 1470 Flags: no-l3-inject Incomplete behavior type: None Fixup: gre Fixup_Flags_2: pmip-udp Nexthop addr: 33.33.33.33 IP FRR MCP_ADJ_IPFRR_NONE 0 OM handle: 0x4217013cDisplays platform software adjacency route processor information for the specified platform allocated index. |
Step 11 |
show ip interface brief
Example: Device(source gateway)# show ip interface brief Interface IP-Address OK? Method Status Protocol Tunnel1 3.3.3.3 YES TFTP up up .... The above output indicates that the relay has no connection from a gateway. The AMT relay interface will be up after it is correctly configured. If the output displays Protocol "down", you must check your configuration. If the interface command shows administratively down, you have not configured the "no shut" in the interface. Displays errors in AMT gateway configuration. |
Displaying and Verifying AMT Gateway Configuration
1.
enable
2.
show ip amt tunnel
3.
show ip mroute
section [group-address]
4.
show ipv6 mroute
section [group-address]
5.
show ip mfib section
[group-address]
6.
show ipv6 mfib
section [group-address]
7.
show platform software
adjacency rp active index
platform-allocated-index-value
8.
show ip interface brief
DETAILED STEPS
Step 1 |
enable
Example: Device> enable Enables privileged EXEC mode. | ||
Step 2 |
show ip amt tunnel
Example: Device(destination gateway)# show ip amt tunnel AMT Gateway tunnel Tunnel1: Local address UDP port 5.5.5.5 54358(0xD456) Remote address 3.3.3.3 2268 (0x8DC ) Total active Relays: 1 Device(source gateway)# show ip amt tunnel AMT Relay tunnel: Local address UDP port 3.3.3.3 2268 (0x8DC ) Remote address Expire time 5.5.5.5 54358(0xD456) 00:03:53 Connected to 1 Gateway The above output is displayed if both relay and gateway is working correctly. Displays AMT gateway configuration. | ||
Step 3 |
show ip mroute
section [group-address]
Example: Device# show ip mroute section 232.1.1.1 (101.0.0.2, 232.1.1.1), 2d00h/00:02:54, flags: sTI Incoming interface: Tunnel10, RPF nbr 0.0.0.0, Mroute Outgoing interface list: GigabitEthernet0/0/4, Forward/Sparse, 2d00h/00:02:54Displays information about the IP multicast routing (mroute) table for the specified multicast group. | ||
Step 4 |
show ipv6 mroute
section [group-address]
Example: Device# show ipv6 mroute section 232.1.1.1 (2011::101:0:0:2, FF3F::232:1:1:1), 2d00h/never, flags: sTI Incoming interface: Tunnel10 RPF nbr: :: Immediate Outgoing interface list: GigabitEthernet0/0/4, Forward, 2d00h/neverDisplays information about the IPv6 mroute table for the specified multicast group. | ||
Step 5 |
show ip mfib section
[group-address]
Example: Device# show ip mfib section 232.1.1.1 (101.0.0.2,232.1.1.1) Flags: HW SW Forwarding: 0/0/0/0, Other: 0/0/0 HW Forwarding: NA/NA/NA/NA, Other: NA/NA/NA Tunnel10 Flags: A GigabitEthernet0/0/4 Flags: F NS Pkts: 0/0Displays the entries and interfaces in the IPv4 Multicast Forwarding Information Base (MFIB) for the specified multicast group. | ||
Step 6 |
show ipv6 mfib
section [group-address]
Example: Device# show ipv6 mfib section 232.1.1.1 (2011::101:0:0:2,FF3F::232:1:1:1) Flags: HW SW Forwarding: 0/0/0/0, Other: 0/0/0 HW Forwarding: NA/NA/NA/NA, Other: NA/NA/NA Tunnel10 Flags: A GigabitEthernet0/0/4 Flags: F NS Pkts: 0/0Displays the entries and interfaces in the IPv6 Multicast Forwarding Information Base (MFIB) for the specified multicast group. | ||
Step 7 |
show platform software
adjacency rp active index
platform-allocated-index-value
Example: Device# show platform software adjacency rp active index 0x57 Number of adjacency objects: 19 Adjacency id: 0xf8000126 (4160749862) Interface: Tunnel10, IF index: 18, Link Type: MCP_LINK_IP Encap: 45:0:0:0:0:0:0:0:ff:11:63:95:21:21:21:21:b:b:b:b:e8:48:8:dc:0:0:0:0:6:0 Encap Length: 30, Encap Type: MCP_ET_TUNNEL, MTU: 1470 Incomplete behavior type: None Fixup: gre Fixup_Flags_2: pmip-udp IP FRR MCP_ADJ_IPFRR_NONE 0 OM handle: 0x4216aaf4Displays platform software adjacency route processor information for the specified platform allocated index. | ||
Step 8 |
show ip interface brief
Example: Device(destination gateway)# show ip interface brief Interface IP-Address OK? Method Status Protocol Tunnel1 5.5.5.5 YES TFTP up down
|
Example: AMT Relay Configuration
enable configure terminal interface Tunnel10 ip address 11.1.1.1 255.255.255.0 no ip redirects ip pim sparse-mode ip igmp version 3 ipv6 enable tunnel source Loopback0 tunnel mode udp multipoint tunnel dst-port dynamic tunnel src-port dynamic amt relay traffic ip amt relay traffic ipv6 exit ip multicast-routing distributed ipv6 multicast-routing ip pim ssm default end
Example: AMT Gateway Configuration
enable configure terminal interface Tunnel10 ip address 33.1.1.1 255.255.255.0 ip pim passive ip igmp version 3 ipv6 enable ipv6 pim passive tunnel source Loopback0 tunnel mode udp ip tunnel destination dynamic tunnel dst-port dynamic tunnel src-port dynamic amt gateway traffic ip amt gateway traffic ipv6 amt gateway relay-address 167.3.0.1 exit ip multicast-routing distributed ipv6 multicast-routing ip pim ssm default ipv6 multicast pim-passive-enable ip route 101.0.0.2 255.255.255.255 Tunnel10 multicast ipv6 route 2011::101:0:0:2/128 Tunnel10 multicast end
Additional References for Automatic Multicast Tunneling
Related Documents
Related Topic |
Document Title |
---|---|
Cisco IOS commands |
|
IP Multicast commands |
Technical Assistance
Description |
Link |
---|---|
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Feature Information for Automatic Multicast Tunneling
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Feature Name |
Releases |
Feature Information |
---|---|---|
Automatic Multicast Tunneling |
Cisco IOS XE Release 3.15S |
Automatic Multicast Tunneling (AMT) provides a method to tunnel multicast data over a unicast network. The tunneling is performed between AMT relays and AMT gateways, using User Datagram Protocol (UDP) encapsulation. In Cisco IOS XE Release 3.15S, this feature was introduced on Cisco ASR 1000 Series Aggregation Services Routers. The following commands were introduced or modified by this feature: amt gateway traffic ip, amt gateway traffic ipv6, amt gateway relay-address, amt relay traffic ip, amt relay traffic ipv6, show ip amt tunnel, show ip amt vrf, show ipv mfib detail, show ipv6 mfib detail, show ip mroute detail, show ipv6 mroute detail, show platform software adjacency fp active, show platform software adjacency rp active, show platform software ip rp active mfib, show platform software ip fp active mfib, show platform software ipv6 rp active mfib, show platform software ipv6 fp active mfib, show platform software mlist. |