The state of the database at this level.
The value 'off' indicates that IS-IS is not active at
this level.
The value 'on' indicates that IS-IS is active at this
level, and not overloaded.
The value 'waiting' indicates a database that is low on
an essential resource, such as memory.
The administrator may force the state to 'overloaded'
by setting the object ciiSysLevelSetOverload.
If the state is 'waiting' or 'overloaded', we originate
LSPs with the Overload bit set.