Owners Manual

Monitoring Network Availability | Performance Monitoring
OMNM 6.5.2 User Guide 377
General Retention Policy Options
Policy Name —A text identifier for the policy.
Description —An optional description for the policy.
Detail/Hourly/Daily Data (Days) —How many days to retain the selected data.
The amount retained has both a performance and data storage impact. For example, retaining
day’s information from an active performance SNMP monitor configured with one target’s
worth of data, retrieved on one minute intervals can consume 0.7 G of database, and require
21 insertions per second. See
Understanding Performance Monitoring on page 361 for more
about retention policies, monitors and how they impact performance.
Active Monitor Members
Select from Available Monitors on the left, and click arrows to move the desired monitor(s) to the
Selected Monitors on the right.
Click
Save to preserve your edits, and include the monitor as listed among existing Retention
Policies
, or click Cancel to abandon any changes.
Aggregate Data
OpenManage Network Manager uses detail polling data to produce aggregate values for larger
intervals of time, including hourly and daily periods. Here is how this works: at the end of each
hour, the detail polling data for the previous hour is aggregated (or as we can say "rolled up") into
hourly data. The resulting hourly records are always given the polled time that is the start of the
hour, but these data points represent the aggregation across the entire hour. For example, if there is
a monitor that polls its targets every 5 minutes, then during the 10 am hour it will poll 12 times and
it will have results for each target and for each attribute for each time it polls. Then when the 11
am hour begins, OpenManage Network Manager will aggregate all of the detail polling data
collected between 10:00 am and 10:59 am and these new hourly data points will be given the polled
time 10:00 am. Likewise, at the end of each day, OpenManage Network Manager will aggregate all
hourly data into daily data, and all new daily data points will be given the polled time of midnight
of the previous data. These daily data points should be understood to represent an aggregation
across the entire day.
You can also report on longer aggregation periods, including Weekly, Monthly, Quarterly, and Yearly,
but these values are computed on-the-fly and are not stored in the database. See
Create a Monitor
Report
for more information about how to generate reports for monitoring data.
Deployment and Polling of Monitor Targets
For each active monitor, the polling targets are deployed and OpenManage Network Manager polls
the appropriate attributes every interval. There are two ways of defining the targets for a given
monitor: explicit and implicit. Explicit targets are defined by selecting the specific devices that
should be polled (equipment managers, subcomponents, etc.) Implicit targets are defined by
configuring a monitor to poll a group of devices, where the group implicitly includes certain devices
based on certain filter criteria. Explicit targets can only be added or removed if you edit the
monitor. Implicit targets can be added and removed any time a device is added or removed from
inventory or some attribute of a device changes. When implicit targets are removed from a
monitor, they are not deleted but they are changed from active to inactive. Only active targets are
deployed. Inactive targets are not deployed, but you can still report on the polling data that is
associated with inactive targets.