Multiple program instances

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It is sometimes desirable to install multiple program instances on a single computer.  Crash Magic supports this when installed as a service or when installed as an ISAPI into IIS.  This is an advanced topic.  Installing multiple instances of Crash Magic should only be undertaken after consulting your DBA as well as your web server administrator.  


This feature makes possible access of the program on a single computer with different URL's.  For example:


Under IIS:






This feature can be useful when hosting Crash Magic for multiple clients.  Crash Magic is capable of hosting multiple configurations and user groups with a single instance.  However, using multiple instances can isolate each client's process and avoid having malfunctions on one system affect another.

This feature is also very useful when testing an installation. (i.e. moving from testing to production)  By using two different instances, you can host two different versions of the program on the same system.


Each Crash Magic installed instance resides in it's own pair of folders. The base folders are c:\program files (x86)\pdmagic and c:\programdata\pdmagic.  Each instance get's its own sub-folder named cmo<instancename>. The program determines where it is being launched from and finds it's paired ProgramData folder.


Multiple IIS instances:

The steps for installing Crash Magic as an ISAPI in IIS are described in the Getting Started chapter.  Repeat the steps for installing in IIS for each instance.  


Since IIS manages IP address and ports, these values are ignored when installed as an ISAPI.

It is generally not necessary to create a new user and/or application pool for each instance.  These are often shared.  

A second application pool can be useful if one instance is a non-robust beta instance and the main instance needs to stay running in all cases.

Since each instance is created by copying the application dll to its own virtual folder, each dll must be registered as its own service extension.  (as described in the steps for installing in IIS 6)

Each instance will have it's own CrashMagic.ini in the virtual folder. Typically this ini only contains the name of the configuration within the CrashMagic.xml configuration file.  In some cases it may be desirable to use a second configuration file. (i.e. if two versions of the program use incompatible configuration files)  In this case, the CrashMagic.ini file may also include a CfgFileName setting.  The CrashMagic.ini file would then have the following format:


 CfgFileName=c:\program files\pdmagic\CrashMagicBeta\CrashMagic.xml

Each instance must use different system tables and/or a different database.  It is not safe for multiple instances to have the same SYS tables.

Each instance must have a different log files directory

Each instance must have a different cache directory