proc DeviceGroupProtocolStacksNgpf { deviceGroup ipType} {
    # This Proc is an internal API for VerifyArpNgpf.
    # It's created because each deviceGroup has IPv4/IPv6 and
    # a deviceGroup could have inner deviceGroup that has IPv4/IPv6.
    # Therefore, you can loop device groups.
    set unresolvedArpList {}
    foreach ethernet [ixNet getList $deviceGroup ethernet] {
	foreach ipProtocol [ixNet getList $ethernet $ipType] {
	    # sessionStatus could be: down, up, notStarted
	    set sessionStatus [ixNet getAttribute $ipProtocol -sessionStatus]
	    set resolvedGatewayMac [ixNet getAttribute $ipProtocol -resolvedGatewayMac]
	    #puts "resolvedGatewayMac: $resolvedGatewayMac"
	    #puts "sessionStatus: $sessionStatus"
	    # Only care for unresolved ARPs.
	    # resolvedGatewayMac: 00:01:01:01:00:01 00:01:01:01:00:02 removePacket[Unresolved]
	    # Search each mac to see if they're resolved or not.
	    for {set index 0} {$index < [llength $resolvedGatewayMac]} {incr index} {
		if {[regexp ".*Unresolved.*" [lindex $resolvedGatewayMac $index]] == 1} {
		    # Getting in here means the interface should be up
		    set multiValueNumber [ixNet getAttribute $ipProtocol -address]
		    set srcIpAddrNotResolved [lindex [ixNet getAttribute [ixNet getRoot]$multiValueNumber -values] $index]
		    puts "\tFailed to resolve ARP: $srcIpAddrNotResolved"
		    lappend unresolvedArpList "$srcIpAddrNotResolved"
		    
		}
	    }
	}
    }
    
    if {$unresolvedArpList == ""} {
	puts "\tARP is resolved"
	return ""
    } else {
	return $unresolvedArpList
    }
}