Installation and Upgrade > Installation and Configuration Guide - Update Existing Installation > Updating an Existing Installation > Preparing Your System for the Update
  
Preparing Your System for the Update
To make the most of working through any update issues on your test system, you must ensure that your test system and your production system are synchronized. If your production system contains code that is not on your test system, then updating your test system may not be as helpful as expected.
Before you update your solution, take your system offline by stopping any web server, servlet engine, and Windchill servers that could interact with the Windchill product files. This includes closing any application that may have a Windchill file open (for example, a text editor, a Windchill shell, or a Windchill log file).
Next, delete the content of the Windchill\Embedded Servlet Engine\instances\ folders.
When your system is offline, but before installing the maintenance release, you must perform all necessary backups. Backing up your files is an important step in the process. If you do not have backup files, you may not be able to restore files if an error occurs.
At a minimum, you should back up the following:
Windchill database—Use the database backup procedures available for the Oracle or SQL Server environment. This backup must follow your site’s data recovery processes.
Windchill solution installation directory—By default, this is C:\ptc\Windchill_11.x or /opt/ptc/Windchill_11.x. Back it up by creating a duplicate copy of it and keep it somewhere that follows your site’s data recovery processes.
Windchill solution LDAP directory content (LDIF file)—Execute the LDAP export procedure described in “Exporting Entries to an LDIF File”. Store the LDIF file somewhere that follows your site’s data recovery processes.
PTC Solution Installer Global Registry directory—Create a duplicate copy of the PTC Solution Installer Global Registry directory called "installer" located in the <Windchill> directory. Keep this PTC Solution Installer Global Registry directory somewhere that follows your site’s data recovery processes.
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Data in JMX database statistics tables is purged on a regular basis in Windchill. This data is used to populate server charts available from the Site > Utilities > Server Status page and various information provided by links from the Site > Utilities > Server Status > Monitoring Tools page in Windchill. If data exists in these tables during an update or upgrade, it is not migrated to the target system.
The ExportPerfTables command line utility can be used to export these tables before updating or upgrading, and the ImportPerfTables command line utility can be used to import them into the target system after update or upgrade. For more information, see https://support.ptc.com/appserver/cs/view/solution.jsp?source=subscription&n=CS182390
For more information about Server Status, see the Server Status.topic in the Windchill Help Center.