proc ModifyIgmpGroupRanges { portList igmpGroupCount } {
    # portList = One port or a list of ports in format of: "1/2 1/3 1/5"
    # igmpGroupCount = A list of group counts for each port: "100 200 300"

    # For example:
    #    If modifying one port, then: 1/1 200
    #    If modifying two ports, then: "1/1 1/2" "100 200"

    if {[llength $portList] != [llength $igmpGroupCount]} {
	puts "\nError: ModifyIgmpGroupRanges: The number of portList and igmpGroupCount are not the same"
	return 1
    }

    for {set index 0} {$index < [llength $portList]} {incr index} {
	set port [lindex $portList $index]
	set vport [GetVportMapping $port]

	foreach igmpHostNumber [ixNet getList $vport/protocols/igmp host] {
	    foreach igmpHostGroupNumber [ixNet getList $igmpHostNumber group] {
		puts "\nModifyIgmpGroupRanges: $port igmpGroupCount=$igmpGroupCount"
		ixNet setAttribute $igmpHostGroupNumber -groupCount [lindex $igmpGroupCount $index]
		ixNet commit		
	    }
	}
    }
    return 0
}