Error loading Agent.jar

Products

• CA Application Performance Management Agent (APM / Wily / Introscope)
• INTROSCOPE

Issue/Introduction

When enabling APM Java Agent within JVM arguments for an Application Server this error is being logged:

Error opening zip file or JAR manifest missing : /opt/tools/introscope/example/wily/Agent.jar

Error occurred during initialization of VM agent library failed to init: instrument

In addition no Agent logs are being created.

 

Environment

Release: APM 10.x

Cause

There are multiple reasons that could cause this issue/error to show up during initialization of JVM such as:

• Corrupted Agent binaries (Agent.jar) either because of corrupted install or non binary FTP transfer when copying from other machine
• Incorrect path to the Agent.jar
• Incorrect permissions
• JVM incompatibility with APM Java Agent

Resolution

Unix user id that was running the application server didn't have read permissions to the top level Agent installation directory, as a result of which it was failing to load the Agent.jar. Providing required read/write/execute permissions on the Agent install folder should address the issue.