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HP B6960-90078 User Manual

Page 289

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Backup

Pre- and Post-Exec Commands

Chapter 5

259

Key Points

Check the following before configuring

pre-

and

post- exec

commands

for a backup specification on a local or remote host:

✓ If a

pre-exec

command fails (returns a non-zero value), the backup

status of the session is set to

failed

and the session is aborted.

✓ If a

post-exec

command fails (returns a non-zero value), the backup

of the session is set to

completed with errors

.

✓ The

pre-

and

post-exec

commands for a backup specification are by

default NOT executed during a preview of a backup. This behavior is
defined by the

ExecScriptOnPreview

variable in the global options

file. See “Global Options File” on page 523 for details.

✓ While the

pre-

or

post-exec

commands are running, the backup

session cannot be aborted.

✓ The

pre-

and

post-exec

processes operate in the background mode.

Therefore, do not use any interactive commands for

pre-

and

post-

exec

processing.

✓ The

pre-

and

post-exec

scripts have to send some output at least

every 15 minutes by default, or the sessions waiting for the scripts
are aborted. You can change this time interval by modifying the

ScriptOutputTimeout

variable in the global options file.

✓ Time-out is provided. If no message is received within the specified

time-out in seconds, the session is aborted.

✓ If there is no executable script on the host or if the path of the script

is wrong, Data Protector displays an error message that the script
failed and the session is aborted.

✓ If a command writes any text to

stdout

, this text is sent to the

Session Manager and written to the database. A

stderr

is redirected

to

/dev/null

. You can redirect it to

stdout

to get error messages

logged to the database.

NOTE

A

pre- or post-exec

script may hang because it did not close all file

descriptors before forking a new process. If the new process runs in the
background and does not exit, such as, for example, the database server
process (

dbstart

), the scripts hang. You can use the

detach

command.

The source of the

detach

command is provided in the

detach.c

file, but

is officially unsupported. For example: