Hi,
You can back up sharepoint service via the SQL agent. You can perform only full database backup.
The Windows SharePoint Services feature pack utilizes a SQL (MSDE) instance called SHAREPOINT as a repository for shared information and collaboration data.
On Windows Server 2003, in the absence of a VERITAS SQL Agent installation, the SQL SHAREPOINT instance can be protected by the Shadow Copy Components file system.
For more information refer 10.0 admin manual page 326:
http://seer.support.veritas.com/docs/269777.htm
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