Cisco Cisco E-Mail Manager Unity Integration Option User Guide

Follow these guidelines to ensure that your Historical Data Server is configured to meet your reporting
needs:

•

Determine the size of the HDS. The size of the database depends on the size of your configuration
and the amount of time for which you want to retain data.

Configuration that impacts the size of the HDS includes the number of call types, skill groups,
agents, skills per agent, routing clients, trunk groups, services, peripherals, scripts, calls routed
daily, and calls terminated daily. The larger the configuration, the bigger the HDS must be to store
data. For example, the historical Call Type database tables store data for each call type for each
five minute and half hour interval.

The amount of time that you want to retain data on the HDS also affects database size. Decide how
long you want to retain reporting data before it is purged automatically from the databases. Data
beyond the configured retention time is purged automatically each day at 12:30.

You can use the ICM Database Administration (ICMDBA) tool to estimate the sizes of your
databases. The tool prompts you for your configuration information and the amount of time that
data is retained in the databases.

•

Determine how you want to backup the HDS.

You can backup the HDS either while the HDS is running or while it is offline (generally when the
contact center is closed or during a time with low call volume).

Generally, performing a backup during peak hours while running is not recommended. Backing
up while the HDS is running might impact performance, especially if you are backing up a large
amount of data. While the HDS database is being backed up, new data from the Logger is stored
in the transaction log. If the transaction log reaches it maximum capacity before the HDS has
completed the backup, updates to the database stop until an administrator manually empties the
log.

Instead, you should backup at a regularly scheduled time when the contact center is not busy. You
can also take the HDS offline and perform a backup. However, the HDS is not available for reporting
when offline. If you plan to backup the HDS database while offline, you might want to configure
a secondary HDS to use for reporting during the backup interval.

•

Determine the HDS backup schedule and the number of days for which data is retained on the
Logger.

You should configure the amount of time that data is stored on the Logger in relation to the schedule
for HDS backups to ensure that you do not lose data in the event of an HDS failure. The Logger
stores data for less time than the HDS. For example, you might store two weeks of data on the
Logger and a year of data on the HDS. When the HDS recovers from a failure, it retrieves all data
from its most recent backup and all of the data on the Logger for the interval for which data is
missing from the backup. For example, if the HDS backup has data up to the last two weeks, the
HDS would replicate the last two weeks of data from the Logger when recovering from a failure.
The amount of data retained on the Logger should cover, at a minimum, the time period between
HDS backups. For example, if the Logger stores data for two weeks, then you need to back up at
least every other week to ensure that you can recover all historical data after a HDS failure.

•

Decide how many Historical Data Servers you require.

For a fault-tolerant system, you should configure two Historical Data Servers; a primary HDS and
a backup HDS. If the primary HDS fails, the Client Admin Workstations automatically connect to
the backup HDS Distributor Workstation.