Virtual TapeServer 6.04.01 Operations and Administration Guide

106 | Using Instant DR
that the operation failed. See Using SecureVTS on page 81 for more information about the
SecureVTS feature. See SecureVTS and failed tape operations on page 153 for an explanation
of the possible failures.
In general, Instant DR should be used if files do not change much from day to day. Data is
transmitted in batches, one or more times per day, and only data differences are sent.
Bandwidth is consumed when the data transmission is scheduled according to policy, usually
during off-peak hours. Instant DR is supported across multiple sites, from one to many
servers based on the configuration.
Instant DR performs well in environments where the backup data does not significantly
change on a daily basis. Synchronizing transaction files, which can change constantly, is not
necessary a good use of Instant DR. Poor performance may result when synchronizing
transaction files because the process by which Instant DR computes file differences can take
longer than copying an entire file. You may also rely on AutoCopy for synchronizing data. See
Using AutoCopy on page 113 to determine if AutoCopy is a better solution for your needs.
If Instant DR is licensed, you can create new Instant DR backup schemes as well as launch
and monitor the remote synchronization processes. You can also automate Instant DR
backups using the VTSPolicy command, if EMS communication is configured (see
Configuring
EMS Communication on page 41). This chapter describes how to perform these tasks.
Creating a backup scheme
To create a backup scheme, you must define a jobset. Each jobset can back up one or more
virtual tapes. Within each jobset, the synchronization tasks are serialized. This means that
two tasks cannot run at the same time. However, you can dispatch separate jobsets, one right
after another, to run multiple synchronization tasks simultaneously, though whether you can
do this depends on the performance capabilities of your NonStop server resources.
Each jobset contains entries that identify virtual tapes to process. A virtual tape is identified
by vault, pool, and virtual tape name. The destination name of the virtual tape on the remote
VTS server can be the same as the source or different, and it is referred to as a target. In a
simple scenario, you can synchronize virtual tapes to the same target names on the remote
system. Also, each jobset can specify many groups, or you can have a separate jobset for each
group.
On the Virtual Media - Instant DR page, a job history log is maintained. You can select an
existing backup set for execution or create a new backup set. You can also dispatch backup
jobs.
Note Before beginning the following procedure, verify that the instant dr option is
available from the window drop-down list on the Virtual Media page. If this option is
not available, the menu_InstantDR parameter must be set to YES in the VTS
configuration file. Edit the configuration file by clicking Supervisor Functions on
the navigation pane and then clicking Edit VTS Configuration File.