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Avoid using the Java JAR command to extract data from ZIP files for WebSphere Application Server products

Technote (troubleshooting)


Previous versions of WebSphere® Application Server for UNIX® platforms were shipped in ZIP format. In the past, it was possible to use the Java™ JAR command to open these ZIP files. However, the JAR command breaks symbolic links and file permissions in zip files for more recent product releases.


Installation images for WebSphere Application Server for UNIX platforms were packaged in the form of zip files to save space. In some earlier versions of the product, it was acceptable to use the Java "jar" command to extract data from those installation images. However, in more recent versions of the product, using the "jar" command will break important symbolic links, and the extracted data will not have proper file permissions.

Resolving the problem

Avoid using the Java "jar" command to extract files from zip files.

Starting with WebSphere Application Server V6.0, many maintenance packages and installation images are shipped in TAR (tarball) format, and can be compressed using gzip. Those packages can be unpacked on any UNIX or Linux-based operating system.

Many UNIX and Linux-based operating systems are shipped with tools which can properly handle zip files. For that reason, some files for UNIX and Linux-based operating systems are shipped only as zip files. In those cases, the operating system which supports those product images should already have a proper unzip tool installed.

For AIX in particular, many maintenance packages are available as both a TAR file and a ZIP file. If your AIX system does not have an unzip tool installed, then download the TAR version of the file you need.

Complete installation instructions, including the use of TAR files, are provided in the WebSphere Application Server Information Center.

Cross reference information
Segment Product Component Platform Version Edition
Application Servers WebSphere Application Server - Express Install and migration AIX, HP-UX, Linux, Solaris, Windows
Application Servers WebSphere Application Server Enterprise General
Business Integration WebSphere Business Integration Server Foundation General
Application Servers Runtimes for Java Technology Java SDK

Document information

More support for: WebSphere Application Server

Software version: 6.1, 7.0

Operating system(s): AIX, HP-UX, Linux, Solaris, Windows

Software edition: Base, Express, Network Deployment

Reference #: 1115941

Modified date: 25 November 2009

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