Frequently Asked Questions - SQL Server
iDataAgent
How do I install SQL Server iDataAgent on a computer where Microsoft SQL Server
Software is not Installed?
Use the
bIgnoreSQLServerCheck
registry key to install the Microsoft SQL iDataAgent
on a computer that does not have the Microsoft SQL server software installed.
Is Microsoft Windows Vista Supported?
Backups using the the SQL Server iDataAgent on Windows Vista are supported as
long as the same User account (and not the local system account) is used to run
the CommVault Communications Service (GxCVD) and for the SQL instance. See Running
Services Using a Windows User and User Accounts for more details. Back to Top
How are Transaction Logs Truncated?
Truncation of transaction logs use the following rules:
Transaction logs will be truncated at the completion of a Transaction Log
backup.
Transaction logs will be truncated every time a checkpoint is processed,
if the database is in truncate mode.
Full and Differential backups do not truncate transaction logs.
Can I Run Log and Full Backups Simultaneously?
Yes. Full and log backup operations can run simultaneously for the same subclient.
However, a full backup needs to exist prior to running them together. After a full
has been run, subsequent parallel backups will work since the risk of breaking the
chain will be lessened. When full and log backup operations are run simultaneously,
the conversion rules will not be honored.
Note that running full and differential backups at the same time is not supported.
How do I Backup a SQL Database in Windows SharePoint Services (WSS)?
To successfully backup a SQL Database in a Windows SharePoint Services (WSS)
environment, where the instance name of the Windows Internal Database resembles
something like MachineName\Microsoft##SSEE, you
need to:
Change the flag Hide Instance to No in SQL Server Configuration
Manager→Protocols for MachineName\Microsoft##SSEE.
Ensure that the SQL Server Browser service is running in SQL Server
Configuration Manager→SQLServer 2005 Services.
Ensure that Named Pipes is enabled in SQL Server Configuration
Manager→Protocols for MachineName\Microsoft##SSEE.
A non-full backup is automatically converted to a full backup in the following situations:
First backup of the subclient.
Re-associating a subclient to another storage policy.
Promote a secondary storage policy copy that is not synchronized with a
primary copy (for all the subclients of a storage policy).
If a backup job within the most recent backup cycle is pruned or disabled
from a primary copy.
Adding a new content path to the subclient.
If you switch from a SnapProtect backup to a traditional backup or vice versa.
CommCell Migration operation.
After the following restore jobs the subsequent backup job for that database
is automatically converted to a full backup:
Point in time restore
Transaction mark restore
Partial ("piecemeal") restore
What happens if I have two databases with the same name?
If you set the SQL Server collation option to case-sensitive and two databases
with the same name are created, the system will only discover one database.
What do I do when I upgrade the SQL Server to a newer version
The system will automatically detect and display the newer version in the CommCell
Console as follows:
The SQL Server version information is refreshed and displayed in the instance
Properties dialog box.
The next backup that is run detects the new version.
The database version of the backup is displayed during the browse operation.
However, if a SQL Server instance on which backups have been run is upgraded
to a newer version and subsequently restored to a time prior to the SQL Server upgrade,
the database will display the older version. To convert the database to a newer
version, perform a full backup of the database after the restore.
How do I restore multiple SQL Server Databases to a consistent time?
For some SQL server environments, you may have multiple databases for which absolute
synchronization of the databases after a restore is critical. Transaction Mark restores
and Point In Time restores are two means of keeping your databases synchronized.
For transaction mark restores, you must administer and maintain your Microsoft
SQL server transaction marks so that they are available for use by the SQL
iDataAgent.
Point in time restores use log backups to get your databases back to a specific
minute and second. Backing up the tail of the log will be critical if you want
to restore to just before the point of failure.
The transparent inclusion during Browse operations provides the ability
to restore data to a selected point in time. When restoring databases to a Transaction
Mark or when using a Point in Time restores, the restore chain consists of the most
recent full, the latest differential (if any), all subsequent log backups taken
prior to the selected browse time, and, transparently, the next log backup after
the browse time.
Are there any considerations when restoring databases backed up by VSS?
VSS-enabled backup jobs must be restored to the original instance.
For restore of databases backed up with VSS, databases can be moved to a
new location on the server and can be renamed. However, data files cannot be
renamed.
To restore any system database that was previously backed up using VSS,
the SQL Server services have to be stopped and restarted in single user mode.
If the database is installed on the system drive, non-system databases will
need to be manually brought back online after the restore.
What are restore chains?
When you pick a restore time, the system determines the optimal combination of
full, differential and log backups necessary to bring back the database(s) to the
selected time. This combination of backups is the restore chain.
For basic database restores, the restore chain consists of the most recent
full, the latest differential (if any), and all subsequent log backups (if any)
taken prior to the selected restore time.
When restoring databases to a Transaction Mark or when using a Point in
Time restore, the restore chain consists of the most recent full, the latest
differential (if any), all subsequent log backups taken prior to the selected
browse time, and, transparently, the next log backup after the browse time.
The transparent inclusion enables restores to a selected point in time.
In what order should system databases be restored?
The master database must be restored first as it has to be online when other
databases are restored.
The msdb database should be restored second as it contains schedules.
The model database can be restored third.
What does the “Unconditionally Overwrite Existing Database or Files” do?
When this option is selected, the data being restored is unconditionally written
to the specified location and overwrites the files of any database that is currently
using the database name specified by you. This implements the T-SQL REPLACE command.
When this options is not selected, the restore job prevents the accidental overwrite
of data files by failing the job.
What is the difference between instance restore and multiple databases restore?
When you perform an instance restore, all the databases are restored in one simultaneous
job. However, if you select multiple databases that are not system databases, they
are restored as multiple jobs.
How are the transaction logs used when browsing the backup data for a File/File
Group restore?
When a browse operation is performed, files that existed as of the most recent
full backup but were removed later will be included in the search results due to
the replaying of the logs. Conversely, if a file was created after the most recent
full backup, the search results will not present it for selection but the transaction
log will re-create this file as part the restore.
How can I reclaim space after transaction log is truncated?
Use the DBCC SHRINKDATABASE command for Microsoft SQL Server to reduce the
size of transaction logs, this will help reclaiming space. For using the
command, refer to Microsoft article DBCC SHRINKDATABASE (Transact-SQL) at
http://msdn.microsoft.com/en-us/library/ms190488.aspx.