Administrator's Guide

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Cisco Unified Attendant Console Administration and Installation Guide
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Chapter 6 Configuring and Licensing Cisco Unified Attendant Console Advanced Server
User Configuration Menu
• Do not install Cisco Unified Replication during SQL Server installation, and do not manually
configure it using SQL Server Feature Selection. Set up server resilience through Cisco Unified
Replication only. If you do install or configure Cisco Unified Replication within SQL Server, you
may experience unexpected results and other problems.
SQL Server Replication
SQL Server replication involves these types of replication:
• Snapshot replication
• Transactional replication
Snapshot replication makes an exact copy (snapshot) of the Publisher and distributes it to the Subscriber;
this includes queue and operator details, and the contact directory. It does not monitor for updates to the
data. Snapshot replication is used to provide the initial data set for transactional replication; and it can
also be used to completely refresh the data on the subscriber. After the initial snapshot, the Subscriber
is kept up to date with the Publisher using transactional replication. Subsequent data transactions
(INSERTed, UPDATEd, and DELETEd data) in the Publisher are captured by the transaction log and
then stored in the distribution database, which acts as a data queue. The changes are then propagated and
applied to the Subscriber in the order in which they occurred.
SQL Server replication uses standalone programs called agents to track changes and distribute data
between databases. The agents are:
• SQL Server Agent—executes scheduled administrative tasks or jobs consisting of one or more job
steps. Job information is stored in the SQL Server. The other agents run as directed by this agent;
and it is required for the Publisher and Subscriber to be able to talk to each other.
• Distributor Agent—moves the snapshot and transactions from Publisher to Subscriber.
• Q Reader—a SQL Server agent that handles the data queues.
• Snapshot Agent—prepares snapshot files containing schema and data of published tables and
database objects, stores the files in the snapshot folder, and records synchronization jobs in the
distribution database.
• Log Agent—monitors the transaction log of each database configured for transactional replication,
and copies the transactions marked for replication from the transaction log into the distribution
database.
You can check how the agents are running using the Monitor Replication function, described in
Monitoring Replication, page 6-51.
Configuring Server Replication
Note The instructions in this section refer to using SQL Server 2008 Standard Edition. If you are using a
different version or edition the steps may be slightly different. Perform the equivalent steps as described
in your SQL Server user documentation.
You configure replication using Cisco Unified Replication, with the following restrictions:
• Full replication functionality is available only if a current resilience license and SQL Server
Standard or Enterprise edition are installed on the Publisher server.