Scheduling services implement the Scheduler MIB (RFC 2591), which supports the following types of scheduling:
Periodic scheduling
Scheduling on the basis of calendar dates
One-shot scheduling
Scheduling services configuration should be performed in the snmpd.conf according to the directives from section “DisMan Schedule MIB”.
Periodic scheduling
Periodic scheduling is based on specific time intervals between two consecutive SNMP set operations initiated by the Scheduler services. A time interval is defined by the number of seconds elapsing between two continuous SNMP statements.
Scheduling on the basis of calendar dates (calendar scheduling)
Scheduling on the basis of calendar dates initiates actions on specific week days or days in a month. A calendar time is specified by giving the month, day, weekday, hour and minute.
You can specify a number of values for each date and thus define complex scheduling operations. The scheduling can for instance initiate a specific action every 15 minutes on a given weekday.
Date specifications based on months, days and weekdays can be defined using the following BITS type scheduler MIB objects:
schedMonth
schedDay
schedWeekDay
Setting several bits in one of these MIB objects has the effect of a logical OR. If, for instance, you set the bits Monday (1) and Friday (5) in schedWeekDay, the scheduling initiates the actions specifically on Mondays and Fridays.
The cross-object combination of bit fields from schedMonth, schedDay and schedWeekDay has the effect of a logical AND. If, for instance, you set the bits June (5) and July (6) in schedMonth and the bit fields Monday (1) and Friday (5) in schedWeekDay, the scheduling is limited to initiating actions exclusively on Mondays and Fridays in the months of June and July.
When specifying dates, you can implement wildcard functionality if you set all bits to "1".
One-shot scheduling
One-shot scheduling is similar to scheduling on the basis of calendar dates. The only difference is that one-shot scheduling is automatically deactivated once an action has been initiated.
Actions
Actions initiated by scheduling model SNMP set operations on MIB objects whose OID is configured in the object schedVariable. The value to be set is specified in the object schedValue. Actions defined in this MIB are limited to INTEGER type objects. This restriction does not however reduce the usability of the scheduler MIB. Simple scheduling is thus possible, e.g. scheduling the activation/deactivation of resources with a corresponding status MIB object (e.g. ifAdminStatus).