Here are a few important details about your new server:

PAS for OpenEdge differs fundamentally from the classic AppServer

Although both PAS for OpenEdge and the classic AppServer run ABL business applications, the architecture and configuration are fundamentally different. PAS for OpenEdge is an application server based on a web server that uses special web applications to run ABL code. It has all the behavior and features of a web server. Although many of the configuration parameters appear to be similar, the tools and techniques for a successful deployment in the multi-session environment are different. For more information about configuring your instance, see the output of the property conversion tool (instance-name/conf/abl_app_name.ubroker_name.oemerge).

The latest release keeps you up to date with security and software updates

In the web environment, tracking the latest security changes is extremely important. The PAS for OpenEdge product is continually being updated with new functionality, bug-fixes, and security patches. Stay current to keep your application secure and stable.

Use property files to change PAS for OpenEdge configuration values

Although PAS for OpenEdge is based on Apache Tomcat, PAS for OpenEdge has simplified the underlying Tomcat configuration and startup for local and remote administration. Rather than making changes to the instance-name/conf/server.xml or instance-name/bin/setenv.[bat|sh] files directly, PAS for OpenEdge uses property files and customer extensible script files. For more information, see Property files.

Check all PAS for OpenEdge log files for errors

A client request traverses multiple PAS for OpenEdge subsystems, any one of which can raise an execution error. The recording of the error occurs in the subsystem-specific log file. Always check all of the log files in the instance-name/logs directory when you investigate execution errors. For more information, see Log files.

PAS for OpenEdge may fail to start because of errors in your ABL application

The PAS for OpenEdge multi-session agent log file distinguishes between ERROR, WARNING, or INFO messages. As a result, the PAS for OpenEdge pasoestart command can report only whether the agent OS process stopped due to startup problems. If pasoestart does not specifically report the startup error, then manually inspect the agent log file in the instance-name/logs directory (abl_app_name.agent.{date}.log) to determine what the startup problem is and correct it.

Configure and load test your instance before moving into production

Choosing the right machine image size and optimal PAS for OpenEdge configuration for that machine image is key in moving your ABL application into the production environment. PAS for OpenEdge is optimized for resource consumption and throughput under load. Unlike in classic AppServer or WebSpeed, you cannot derive ABL application performance using a single client. Test your application with the anticipated number of concurrent clients to ensure that you do not exceed finite resource limits imposed by the OS, OS processes, networking, and OpenEdge database. For more information, see Goals and common steps for tuning PAS for OpenEdge instances.

Stopping a PAS for OpenEdge instance may take some time

Stopping a PAS for OpenEdge instance may take several minutes in some cases. It may even appear hung. PAS for OpenEdge (Tomcat) has a policy that allows its web applications to finish client requests before stopping. A normal PAS for OpenEdge stop does not always stop all of its processes. If you want PAS for OpenEdge not to wait for client requests to finish before stopping, use the pasman stop command with the -F option to force the shutdown.

The Apache Tomcat access log is a great troubleshooting tool

The access log is a great help when you troubleshoot client connection problems, maximum response times, client login failures from hackers, and much more. Even though the access log uses a small amount of processing time and disk space, you cannot get this information easily from other sources and it can be helpful in monitoring the health of your server and tuning its run time. See the Apache Tomcat® Configuration Reference.

Apache Tomcat stuck thread detection is a useful alerting mechanism

The Apache Tomcat stuck thread detection identifies requests that take a long time to process, which may indicate that something is wrong in the request execution. Stuck thread detection is an alerting mechanism that logs a message for requests that take longer than a configurable amount of time to complete. See the Apache Tomcat® Configuration Reference.

UNIX file permissions that only allow the root use

On UNIX, the PAS for OpenEdge production installation and instance tailoring eliminates all access by any user account. After an OpenEdge installation completes, its instances are configured to be started, stopped, configured, and monitored by the root user account (required by the OpenEdge installer). If all your OS administration is performed via the root user account, no action needs to take place. If you follow best practices and never use the OS root user account, then you will need to change file permissions for core and instance executables and scripts. See About user and file permissions.