15-15
Multimedia Traffic Control with IP Multicast (IGMP)
How IGMP Operates
Multimedia Traffic Control
with IP Multicast (IGMP)
Configuration Options for Forced Fast-Leave

Note on VLAN

Numbers:

In the HP Procurve Switch 4108GL, the walkmib and setmib commands use an internal
VLAN number (and not the VLAN ID, or VID) to display or change many per-vlan features,
such as the Forced Fast-Leave state. Because the intern al VLAN number for the default
VLAN is always 1 (regardless of whether VLANs are enabled on the switch), and because
a discussion of internal VLAN numbers for multiple VLANs is beyond the scope of this
document, the discussion here concentrates on examples that use the default VLAN.
Listing the Forced Fast-Leave Configuration
The Forced Fast-Leave configuration data is available in the switch’s MIB
(Management Information Base), and includes the state (enabled or disabled)
for each port and the Forced-Leave Interv al for all ports on the switch.
To List the Forced Fast-Leave State for all Ports in the Switch. Go to
the switch’s command prompt and use the walkmib command, as shown below.
1. From the Main Menu, select:
5. Diagnostics . . .
4. Command Prompt
2. Do one of the following:
•If VLANs are not enabled on the switch, go to step 3.
•If VLANs are enabled on the switch :
i. You will be prompted to select a VLAN. For example:
ii. Because you can list the Forced Fast-Leave state for all ports on
the switch from any VLAN, just press [Enter] to select the displayed
VLAN.
3. Enter either of the following walkmib command options:
walkmib hpSwitchIgmpPortForcedLeaveState
Feature Default Settings Function
Forced Fast-
Leave state
2
(disabled)
1 (enabled)
2 (disabled)
Uses the setmib command to enable or disable
Forced Fast-Leave on individual ports. When
enabled on a port, Forced Fast-Leave ope rates only
if the switch detects multiple end nodes (and at
least one IGMP client) on that port.