The active OAM mode for the port. When a port is
configured in the passive OAM mode and ULD is enabled
in the standard or fast ULD mode, the passive mode is
superceeded by this value. The port will operate as
though it is configured in the active OAM mode. If
the port is configured in the passive mode and ULD is
disabled, the value is passive(1) and OAM will operate in
the passive mode. Otherwise, the value is active(2) and
OAM will operate in the active mode. This enforces the
requirement for ULD that both peers must operate as
active OAM clients.