This object indicates the Source Guard filter mode at
this interface.
active(1) indicates that the Source Guard feature is
active at this interface.
inactiveTrustPort(2) indicates that the Source Guard
feature is inactive because this interface is a DHCP
Snooping trust interface.
inactiveNoSnoopingVlan(3) indicates that the Source
Guard feature is inactive because this interface
does not have a VLAN which has DHCP Snooping enabled.