Virtual TapeServer 8.3 Supplemental Installation Guide

Enabling and Configuring AutoCopy and Instant DR | 27
AutoCopy is enabled at the pool level; all virtual tapes contained in the pool are monitored and
copied when necessary. If VTS fails to copy a virtual tape, it retries the AutoCopy operation every
five minutes for a total of twelve attempts. If the operation fails altogether, a failure message is sent
to the event log.
Note Autocopy will fail if the virtual tape already exists in another pool on the target. Virtual tape
names must be unique across all vaults and pools.
If an encrypted virtual tape is stored on an AutoCopy server and the AutoCopy server attempts to
perform an operation on the tape, Data Encryption must be enabled and the key server that was used
to encrypt the tape must be configured on the AutoCopy server. If not, the tape operation will fail and
an error message is displayed on the AutoCopy server indicating that the operation failed. Refer to
the Virtual TapeServer Configuration Guide for information about Data Encryption and an explanation
of the possible failures.
In general, AutoCopy should be used if files change often throughout the day. VTS automatically
monitors pools designated for AutoCopy. If a change is detected, data is transmitted when each
virtual tape is unmounted. This means that bandwidth may be consumed throughout the day, which
may coincide with user activity on the network. You may also rely on Instant DR for synchronizing
data. See "Overview of Instant DR" on page 26 to determine if Instant DR is a better solution for your
needs.
Event Management System (EMS) and Secure Shell (SSH) are prerequisites for AutoCopy. EMS must
be configured and running correctly as described in the EMS chapter of the Configuration Guide. The
EMS service is responsible for monitoring mounts and dismounts relevant to AutoCopy. SSH must be
configured on the source VTS server (contact your authorized service and support representative if
you need help configuring SSH). AutoCopy performs the copy operation from the source VTS system
to the target VTS system using an SSH transfer, which encrypts communication between the VTS
systems. The VTS systems that receive virtual tape copies do not have to be configured for EMS or
AutoCopy.
AutoCopy assumes that a virtual tape mounted in Read/Write or With Ring mode will be modified
upon dismount. NonStop mount requests that are designated No Ring are mounted as Read Only and
are not automatically copied.
Using Instant DR or AutoCopy
Instant DR and AutoCopy features have distinct advantages that may be specific to individual sites or
requirements. In general, Instant DR should be used if files do not change much from day to day.
AutoCopy is best used if files change often throughout the day. Keep the following in mind when
enabling these features:
Instant DR AutoCopy
How often is data copied? In batches Individually, as each virtual
tape is unmounted
When is data transmitted? Synchronized, once or more
per day
As each virtual tape is
unmounted
How is the feature initiated? By policy scheduling or the Automatically, virtual tapes