HP ProLiant DL980 G7 Server - Manual (Page 47)

availability. More importantly, the Availability Group feature includes support of active secondary
replicas, which dramatically improves resource utilization. Active secondary replicas perform log
backups and copy-only backups of a full database, file, or filegroup.
If a database is a member of an Availability Group, additional parameters will be displayed,
including Availability Group Name, Synchronization Status, and Replica Role.
Figure 37 (page 47)
shows a sample portion of the Database page screen displaying information about Availability
Group parameters. The Replica Role is indicated within parenthesis next to the Availability Group
Name. For example, in
Figure 37 (page 47) , the Availability Group Agroup_SP1 is a primary
replica. Table 3 (page 47) and Table 4 (page 47) lists possible synchronization states and replica
roles, respectively. Possible database status and read-only values are listed in the next subsection
in
Table 5 (page 48) and Table 6 (page 48) , respectively.
Figure 37 Database in Availability Group
Table 3 Possible synchronization status values
Description Value
The synchronization state is Not Synchronizing. NotSynchronizing
The synchronization state is Synchronizing. Synchronizing
The database replica is synchronized with the primary. Synchronized
The database replica is reverting after a failover. Reverting
The principal database is initiating a failover. Initializing
Table 4 Possible replica roles
Description Role
The Role is Resolving. Resolving
The Role is Primary. Primary
The Role is Secondary. Secondary
The Role is Unknown. Unknown
Mirrored database
Database mirroring is used for protecting application databases from planned and unplanned
downtime. Combined with log shipping and failover clustering, database mirroring effectively
meets high availability requirements of mission critical applications. A mirror database is a copy
of the primary database and typically is fully-synchronized with it. When the transaction log buffer
for the principal database is written to disk, transactions are sent directly from the principal database
and server to its mirror database and server.
If a database is configured for mirroring, Mirror Status information will be displayed, as shown in
Figure 38 (page 48) . Possible values for are listed in Table 7 (page 48) . Table 5 (page 48) and
Table 6 (page 48) list possible values for Database Status and Read-Only, respectively.
Optimizations pages: Viewing and controlling optimization recommendations 47