nbsCmmcPortPreferred
1.3.6.1.4.1.629.200.8.1.1.76
Among a group of ports this object per port says whether this
ports is preferred or not. A preferred port in a redundant
group (usually a pair of ports) will always be the active
link if it has link, regardless of the link state of other
ports in its group.
Only one port in a redundant group may be preferred. If other
ports in the same redundant group are already designated
yes(1), the system should automatically set them to no(2).
When a port is selected as preferred port, its redundant
group is assumed to be in revertive mode.
When no port is selected as preferred port, its redundant
group is assumed to be in non-revertive (a.k.a. sticky) mode.
Once selected, a port's actual active state be read via
the SelectLink object.
Use caution in designating Preferred ports, because on
flaky/intermittent lines, this may result in excessive
failovers.
If read as notSupported(1), this port either does not belong
to a redundant group, or its redundant group is always in
non-revertive (a.k.a. sticky) mode.