Modifying IGMP Interfaces

Web Agent Procedure

To modify IGMP interfaces from the Web Agent:

1. Select Interfaces from the Routing > IGMP group on the Web Agent window. The IGMP Interfaces dialog box opens (Figure 12-17)

NOTE: You must first enable “multicast protocol”on an interface before you can configure IGMP. See “Displaying Existing IP Interfaces” earlier in this chapter for more information on how to select a multicast protocol.

Figure 12-17. IGMP Interfaces Dialog Box

2. See Table 12-8 to modify an IGMP interface:

   Table 12-8. IGMP Interface Parameters

   Parameter	Allows you to...
   Select	Select the interface to be modified.
   Interface	Displays the IP interface that is configured with IGMP.
   IP Address	Displays the IP address associated with this interface. NOTE: Note: This parameter is not configurable from the IGMP configuration dialog box.
   IP Address Mask	Displays the subnet mask associated with this interface. NOTE: Note: This parameter is not configurable from the IGMP configuration dialog box.
   IGMP Version	Select the IGMP Version (1.0 or 2.0) to be associated with the IGMP interface.
   Maximum Groups	Enter the number of IGMP Groups that can be active on this interface. The default setting is 32. The valid range for this field is 1 to 7,000.
   Always be Group Membership Querier	Version 1.0 - Select Enable to make this interface the designated querier. The default is Disable. Version 2.0 - Select Enable to force this interface to send queries. The default is Disable which tells the interface to obey the designated querier election. NOTE: Note: Only the designated router will query hosts on your network.
   Process Leave Packets	turns off processing of IGMP leave messages when set to disable. The default value is Enable.
   Query Request Interval in (sec)	Enter a time period between queries. The valid range for this field is 1 to 65,535. The default setting is 125 seconds.
   Query Response Interval in (sec)	Enter a time (in seconds) to wait for a response from a host after a query is sent. If no response is received within this time, the host is removed from the group table. The valid range for this field is 1 to 25. The default setting is 10 seconds.
   Neighbor Querier Timeout Interval in (sec)	Enter a time (in seconds) this interface should wait after hearing a neighbor’s query before assuming the role of querier, if not already the querier. If no query is received from a neighbor with a lower IP address in the allotted time, this interface becomes the querier (IGMP Version 2.0 only). The valid range for this field is 30-600. The default setting is 255 seconds.
   Robustness Variable	Modify this field for any expected packet loss on a subnet. If a subnet is expected to have more packet loss, the Robustness Variable should be increased. The Robustness Variable must not be set to 0 and should not be set to 1. The valid range for this field is 1 to 65,535. The default setting is 2.

3. Click APPLY to save your changes, or CANCEL to restore previous settings.