Event ID 20176 — RRAS Multicast Scope Configuration

Applies To: Windows Server 2008

A multicast scope is a named range of IP multicast addresses that is expressed with an IP address and mask. After multicast scopes are configured, you can use them to create scope-based multicast boundaries in the properties of an IP routing interface.

Routing and Remote Access can forward multicast traffic in limited network configurations. The primary use of Routing and Remote Access as a multicast router is to connect a subnet to a multicast-enabled intranet that contains routers running multicast routing protocols. To fully support efficient multicast forwarding on a multiple-router intranet, you must install multicast routers that run one or more multicast routing protocols.

Event Details

Product: Windows Operating System
ID: 20176
Source: RemoteAccess
Version: 6.0
Symbolic Name: ROUTERLOG_IP_LEAKY_SCOPE
Message: A leak was detected in multicast scope: %1. One of the following routers is configured incorrectly: %2

Diagnose

Use the following commands to troubleshoot multicast routing and forwarding problems:

  • The mrinfo command displays the configuration of a multicast router.
  • netsh routing ip show mfe displays the entries in the multicast forwarding table.
  • netsh routing ip show mfestats displays packet statistics and input and output interface information for multicast forwarding entries in the multicast forwarding table.
  • netsh interface ip show joins displays the multicast groups locally joined on each interface.

For error resolution, see the sections titled "Enable the interface or configure multicast scopes" or "Configure the multicast scope, boundaries, or heartbeat."

Note:   Although the Windows Server 2008 operating system does not provide a version of the Mtrace multicasting tool, a multicast router running Windows Server 2008 does respond to mtrace command queries from other Mtrace tools.

For more information about how to use the mrinfo command and netsh commands for troubleshooting multicast routing and forwarding problems, see Using the IP multicasting utilities (https://go.microsoft.com/fwlink/?LinkID=92730). This information describes multicast troubleshooting in Windows Server 2003.

Resolve

To resolve this issue, use the resolution that corresponds to the cause you identified in the Diagnose section. After performing the resolution, see the Verify section to confirm that the feature is operating properly

Cause

Resolution

Configuration of multicast settings

Configure multicast scope, boundaries, or heartbeat

Network interface or multicast scope

Enable the interface or configure multicast scopes

Configure multicast scope, boundaries, or heartbeat

To perform these procedures, you must have membership in Administrators, or you must have been delegated the appropriate authority.

Follow the procedures in the order in which they appear until the problem is resolved.

Configure multicast scopes

To configure multicast scopes:

A scope is a range of IP multicast addresses and is defined by specifying the address range as an IP address and mask. Multicast addresses in the range of 239.0.0.0 to 239.255.255.255 (239.0.0.0/8) are used to specify administrative scopes, as defined in RFC 2365. However, the range of 239.255.0.0/16 is defined as a local scope and cannot be divided further.

  1. Open Routing and Remote Access. Click Start, click Run, type rrasmgmt.msc, and then press ENTER.
  2. In the console tree, double-click the server name.
  3. Double-click IPv4, right-click General, and then click Properties.
  4. On the Multicast Scopes tab, click a multicast scope, and then click Edit.
  5. Review the settings, and then add or delete the scope, as appropriate.

Configure multicast boundaries

To configure multicast boundaries:

Multicast boundaries are administrative barriers that can be configured to limit how far routers can forward multicast traffic across a network. Without boundaries, a multicast router forwards all multicast traffic throughout the network. With boundaries, a multicast router forwards multicast traffic over a limited area of the network only.

  1. Open Routing and Remote Access. Click Start, click Run, type rrasmgmt.msc, and then press ENTER.
  2. In the console tree, double-click the server name.
  3. Double-click IPv4, and then click General.
  4. In the details pane, right-click the interface on which you want to configure multicast boundaries, and then click Properties.
  5. On the Multicast Boundaries tab, review the scope boundary settings.

Note:  Only scopes configured as multicast scopes are listed in Scope.

Configure multicast heartbeat

To configure multicast heartbeat:

Multicast heartbeat is the ability of a server running Routing and Remote Access to listen for a regular multicast notification to a specified group address to verify that IP multicast connectivity is available on the network. If the heartbeat is not received within a configured amount of time, the server running Routing and Remote Access sets the multicast heartbeat status of the configured interface to inactive.

  1. Open Routing and Remote Access. Click Start, click Run, type rrasmgmt.msc, and then press ENTER.
  2. In the console tree, double-click the server name.
  3. Double-click IPv4, and then click General.
  4. In the details pane, right-click the interface on which you want to configure multicast heartbeat, and then click Properties.
  5. On the Multicast Heartbeat tab, select the Enable multicast heartbeat detection check box.
  6. Add a multicast heartbeat group, and configure a quiet time.

Enable the interface or configure multicast scopes

Confirm that the network interface routing multicast traffic is enabled and a multicast scope is configured.

To perform these procedures, you must have membership in Administrators, or you must have been delegated the appropriate authority.

Follow the procedures in the order in which they appear until the problem is resolved.

Enable the network interface

To enable the network interface:

  1. Open Network Connections and check the status of the network device.
  2. Right-click the network device, and then click Enable.

Configure multicast scopes

To configure multicast scopes:

A scope is a range of IP multicast addresses and is defined by specifying the address range as an IP address and mask. Multicast addresses in the range of 239.0.0.0 to 239.255.255.255 (239.0.0.0/8) are used to specify administrative scopes, as defined in RFC 2365. However, the range of 239.255.0.0/16 is defined as a local scope and cannot be divided further.

  1. Open Routing and Remote Access. Click Start, click Run, type rrasmgmt.msc, and then press ENTER.
  2. In the console tree, double-click the server name.
  3. Double-click IPv4, right-click General, and then click Properties.
  4. On the Multicast Scopes tab, click a multicast scope, and then click Edit.
  5. Review the settings, and then add or delete the scope, as appropriate.

Verify

To verify that multicast traffic is being forwarded to the multicast group address, on a receiving host, open a multicast-enabled application and verify streaming content is being received.

RRAS Multicast Scope Configuration

Routing and Remote Access Service Infrastructure