Backup and Recovery of the SAP Web Application Server (Java) 

Purpose

The backup of the SAP Web AS Java and the relevant database prevents you from data loss and is essential for the recovery of the server after a breakdown of the system.

You can use the backup data to restore your system in various scenarios. For example, you can:

·        Restore the initial state of the system if an installation or upgrade fails

·        Restore the SAP Web AS installation in case of operating system or file system problems

·        Restore the SAP system data if the database crashes, and so on.

You can apply two backup strategies:

·        Offline backup – this strategy enables you to create a full backup of your system, so that it can be restored in case of a hard disk crash or operating system problems. However, it requires system downtime, and therefore cannot be performed on a daily basis.

·        Online backup – using this strategy, you can backup the database and the file system, which enables you to recover only particular components of your system. It does not require full system shutdown, and therefore is convenient for creating incremental data backup.

To ensure that your system can be recovered, you should apply both strategies.

The backups described here are required for the recovery of the Web AS (Java) only. For any other components running on top of it, you must also consider creating backups of any additional databases and file system folders they may be using. For more information, see the documentation for the relevant component.

Prerequisites

The backup tools for your database and the backup solution for your system are installed and available.

Process Flow

Initial Backup

After installation or upgrade of SAP Web AS Java, you need to perform a full backup of your system. For more information, see the relevant installation guides on SAP Service Marketplace at service.sap.com/instguides.

Make sure that you include the following data in the system backup:

·         On Windows platforms, create a backup of the System State.

·         On Unix-type platforms, create a file system backup of the /etc directory.

·         Create a file system backup of the JDK directory.

You should also backup your system before an upgrade.

Regular Backups

After you have created a full system backup, you should perform regular online backups of the following components.

Database

We recommend that you include the online backup of the database as well as the logs in the daily routine.

You can create a backup copy of your database so that you can recover the database if errors occur. For more information, see the table below.

If you are reading a print version of this documentation, you can find the documentation listed below at:

help.sap.com/nw04 ® English ® SAP NetWeaver ® Application Platform (SAP Web Application Server) ® Databases

Then choose the path given below.

Documentation for Database Backup and Recovery

Database	Link	Path
IBM DB2 Universal Database for iSeries	Backup and Recovery	IBM DB2 Universal Database for iSeries ® SAP Database Guidelines: IBM DB2 Universal Database for iSeries
IBM DB2 Universal Database for UNIX and Windows	Backup and Recovery	IBM DB2 Universal Database for UNIX and Windows ® CCMS: SAP/DB2 for UNIX and Windows
Informix	Data Recovery for Informix	IBM Informix  ® SAP Database Guide: Informix
MaxDB	Backup Restore	MySQL MaxDB ® Basic Information  ® Database Administration ® Security Concepts
MS SQL Server	Database Backup  Database Restore	SAP / MS SQL Server 2000 DBA in CCMS
Oracle	Database Backup Restore and Recovery	SAP Database Guide: Oracle ® Approach to Oracle DBA

For many databases, you can also schedule database backups in the Database Planning Calendar, which is part of the Computing Center Management System (CCMS) provided by SAP. For more information, see the table below.

If you are reading a print version of this documentation, you can find the documentation listed below at:

help.sap.com/nw04 ® English ® SAP NetWeaver ® Solution Life Cycle Management ® System Management ® Database Administration in CCMS

Documentation for Scheduling Database Backups in Computing Center Management System (CCMS)

Database	Link	Path
IBM DB2 Universal Database for UNIX and Windows	The DBA Planning Calendar	CCMS: SAP/DB2 for UNIX and Windows ® Jobs
Informix	DBA Planning Calendar	CCMS: Informix
MaxDB	DBA Planning Calendar	CCMS: MySQL MaxDB ® Database Administration in CCMS: MySQL MaxDB
MS SQL Server	Backing Up with the SAP System	SAP / MS SQL Server 2000 DBA in CCMS ® Database Backups ® Executing Backups
Oracle	DBA Planning Calendar	CCMS: Oracle

To ensure data consistency during online backup, you should schedule inactivity phases for database administrators and end users to ensure that no write operations are performed during backup.

File system

For successful system recovery, the backup of the following files and folders is required:

·        The global share directory (<sapmnt>/<SID>). For more information, see the relevant installation guide on SAP Service Marketplace at http://service.sap.com/instguides.

As part of this backup, you must have the <sapmnt>/<SID>/SYS folder.

·        The bootstrap.properties file, which is located in the following directories:

¡        On Windows platforms, in <drive>:\usr\sap\<SID>\JC<instance_number>\j2ee\cluster\bootstrap.

¡        On Unix platforms, in /usr/sap/<SAPSID>/DVEBMGS<instance_number>/j2ee/cluster/bootstrap.

To ensure that no changes are made to the file system during backup, stop the Software Deployment Manager (SDM).

·        The instance.properties file, which is located in the following folder:

¡        On Windows platforms, in <drive>:\usr\sap\<SID>\JC<instance_number>\j2ee\cluster.

¡        On Unix platforms, in /usr/sap/<SAPSID>/DVEBMGS<instance_number>/j2ee/cluster.

The following backups are recommended:

·        SDM

We recommend that you backup SDM after each deployment.

Create a backup of the SDM installation directory /usr/sap/<SID>/JC<inst_nr>/SDM.

Make sure the SDM is stopped during backup.

·        Instance configuration backup

You can export the configuration of the Java instances in the cluster using the Config Tool. For more information, see Exporting and Importing a Configuration in the Administration Manual.

You can use this backup to restore the configuration of the system. For example, if you remove a server process, you can restore it by importing the instance configuration backup. This does not overwrite the changes that you may have made to the system meanwhile.

You do not need to back up the following files and folders:

·        Work folders – such folders typically contain files that may be open during the online backup, therefore you cannot copy or back them up.

·        Folders that contain dispatcher and server processes binaries:

¡        <SAP_installation_dir>\j2ee\cluster\dispatcher

¡        <SAP_installation_dir>\j2ee\cluster\server<N>

If you remove these folders from your backup, make sure also that it does not contain the version.bin file in the cluster directory.

Restoring the System

       1.      Install a new SAP Web AS Java system using SAPInst, or restore the file system from the offline backups that you created.

       2.      Import the database backup using the relevant tools provided by the database vendor.

       3.      Overwrite the SAP system directory /usr/sap/<SID>.

       4.      If the SDM backup is more recent than the backup of the SAP system directory, overwrite the SDM directory as well.

       5.      Restart the system (see Starting and Stopping the SAP System).

Result

The J2EE Engine is restored with the last backup.