Data Protector Express User's Guide (TC330-96002, October 2010)

Rotation type and Sets
This setting is
only available when the job is scheduled to run repeatedly. The Rotation type and Sets
controls allow
you to specify a set of precongured rotations. The Custom Rotation type is a special
case. It u nloc
ks the user interface to allow the user to congure his own rotation. For more information
about setting up rotations, see Chapter 7.
Type of xed rotation
This setting is only available when creating a custom rotation. For more information about setting up
rotations, see Chapter 7.
Mode Setting
s
The Mode box c
ontains several settings the control the t ype of backup a nd automatic verify that will b e
performed,
how used media will be treated, and what to do when a le won’t t on the current media.
Man of these settings are set automatically when a schedule rotation is in effect. When a rotation controls
theses set tings they become d isabled in the Administrator.
Backup mode
Data Protector Express suppor ts the back modes listed below. For scheduled automatic rotation jobs,
Data Protector Express uses the backup m ode for each backup set as indicated on the Schedule page; for
unschedule d or manual jobs, Data Protector Express uses the settings set by the user.
Full This setting instructs D a ta Protector Exp ress to back up all selected les.
Differential This setting instructs Da ta Protector Express to back up all selected les that have changed
since the last full backup.
Incremental This setting instructs Data Protector Express to back up a ll selected les that have changed
since the last full, differential, or incremental backup.
Copy This setting instructs Data Protector Express to back up all selected les,butithasnoeffectonany
future scheduled job. Use this op tion when you wish to make a record of les or systems at a particular
time, but do not wish to disrupt the normal backup schedule.
CAUTION:
Incremental jobs are the shortest and smallest jobs to run, but they present some issues related to full data
recovery. The difference between an incremental and a differential backup is important -- incremental
backup jobs back up only les that have changed since the last full, differential or incremental backup,
while differential backup jobs back up all les changed since the last
full
backup. If incremental backup
media sets are overwritten or recycled before another full backup is performed, this can create a gap in
available data if you need to recover les from the overwritten media.
Exclusive use of incremental backup jobs to ensure full data recovery after a disaster is not recommended,
unless you are using a schedule that retains one full backup and all subsequent incremental backups
before overwriting any media. However, to ensure successful data recovery with incremental jobs, follow
these guidelines:
Have at least as many incremental media as there are d ays between full or differential backup jobs. For
example, if you run full backup jobs every ve days, have at least four incremental media; if you run full
backup jobs every seven days, have at least six incremental media.
Never recycle incremental media between differential or full backup jobs. If you run more than one
incremental job in a row, be certain to not recycle any of the media used during this string of incremental
jobs.
User’s Guide
27