Source:Informix Backup

Overview

This article describes Informix integration key features and backup configuration. For detailed information on prerequisites and installation requirements, see Informix Configuration.

SEP sesam online backup for Informix (SIB) provides the Backup Services API (XBSA) between Informix and SEP sesam for saving Informix data to the SEP sesam Server. XBSA specifies the access from Informix ON-Bar utility to a backup application. During backups and restores, ON-Bar uses XBSA to exchange the data from specified storage spaces (dbspaces) or logical-log files. SEP sesam manages the whole storage media, whereas ON-Bar decides which data has to be saved or recovered. For details on Informix concepts and utilities, see IBM Informix documentation.

Creating a backup task

During a backup (or restore), the ON-Bar utility controls the data streams. This utility must be integrated with a SEP sesam Server to access the storage devices.

Create a new backup task for the Informix server.

1. From Main Selection -> Tasks -> By clients, select Informix client and click New backup task. The New backup task window opens.
2. Specify the Source as Informix instance. The instance should map to the instance which is used during onbar backup command. You can either browse for the databases that you want to include in the backup or enter their names followed by a comma. Note that by browsing the source (not entering it manually), the task type and task name are set automatically.
   Click OK to create the task.

Configuring Informix

To give ON-Bar the necessary information to connect to SEP sesam, set the following environment variables:

Mandatory parameters

INFORMIXDIR

Set by Informix installation.

SESAM_SERVER=<SEP sesam Server name>

SESAM_JOB=<Informix backup task name>

Name of an already configured backup task on the SEP sesam Server which you had to create earlier.

SESAM_POOL=<Media pool name>

Name of an already configured media pool on the SEP sesam Server.

Optional parameters

XBSA_TRACE=<Trace level> (0|1|2)

If set with +10000000, then process logs to STDERR, e.g., 'set XBSA_TRACE=10000002'.

XBSA_LOGFILE

<Name of trace file>

	Note
	Although XBSA_TRACE and XBSA_LOGFILE are not mandatory, they should be set to get information in case of problems during the backup or restore. For the restore only SESAM_SERVER and SESAM_JOB are mandatory.

Configuring ON-Bar backup

During backup, the Informix ON-Bar utility provides the interface to the databases and performs extraction and insertion of the data. You must run the onbar command to start a database or logical logs backup as an Informix or a root user.

	Note
	You have to check the onbar return code, because onbar does not write error messages to STDERR (standard error output). For details on the return codes, see ON-Bar messages and return codes.

The following examples show, how to start backups on the Informix server.

• Backup of the tablespace dbspace01:
informix@linux:/opt/informix/> export SESAM_SERVER=backupsrv informix@linux:/opt/informix/> export SESAM_JOB=informix_ts informix@linux:/opt/informix/> export SESAM_POOL=DISK informix@linux:/opt/informix/> onbar -b -L 0 dbspace01 informix@linux:/opt/informix/> echo $? 0 informix@linux:/opt/informix/>
• The commands shown in the following example:
Perform a backup level 0 of the dbspace01 on an OnLine Dynamic Server instance named venus. Back up all logical-log files associated with dbspace01, close the session and then back up the current logical log. setenv SESAM_SERVER jupiter setenv INFORMIXDIR /usr/informix setenv INFORMIXSQLHOSTS \$INFORMIXDIR/etc/sqlhosts setenv ONCONFIG onconfig.std onbar -b -L 0 dbspace01 onbar -b -l -c
• The SEP sesam extension for Informix (Windows, ZIP archive) contains the sbc_onbar.cmd command, which is suitable to back up Informix instances from the SEP sesam command events by adapting INFORMIX_... and SESAM_... values. The arguments are transfered to onbar command and typical calls are sbc_onbar.cmd -b -L 0, or sbc_onbar.cmd -v.

ON-Bar commands

You have to use a relevant onbar -b command to back up storage spaces (dbspaces) or logical logs.

• Complete backup of the database (if necessary, start the database with oninit -v command)
onbar -b -w [-L n] n - Backup level (0, 1, 2), default is 0.
• Backup of a single dbspace
onbar -b [-L n] n - Backup level (0, 1, 2), default is 0. dbspace_name - Name of the Informix dbspace instance
• Logical-log files backup
onbar -b -l - Backup of all full logical-log files onbar -b -l -c - Backup of the actual logical-log files and switch to the next logical-log file. onbar -b -l -s - Backup of all logical logs, which reside on the hard disk after a crash of the database.