Under some circumstances, particular Internet browsers may rename a downloaded IBM WebSphere Application Server Interim Fix, Fix Pack, or Refresh Pack file with a ".pak.zip" file name extension, even though the original file name only has a ".pak" extension. It is possible for older versions of the UpdateInstaller to install the ".pak.zip" file without error, but the UpdateInstaller is unable to uninstall a fix which was installed with that file name extension.
The standard file name extension for maintenance packs is ".pak"
Maintenance packs for Application Server versions 6.0, 6.1, and 7.0, which include Interim Fixes, Fix Packs, and Refresh Packs, are normally distributed to clients in the form of ".pak" files. The name of the maintenance pack file uses ".pak" for the file name extension. The UpdateInstaller utility responsible for installing maintenance packs expects a fix to use a ".pak" file name extension. This is an important distinction for the UpdateInstaller.
A maintenance pack file may incorrectly have a ".pak.zip" extension when downloaded
Certain internet browsers on Windows-based operating systems may rename a ".pak" file downloaded from the Application Server support site to ".pak.zip". In other words, a ".zip" file name extension is appended to the end of the original file name. Although the original name of the file contains a ".pak" file name extension, the browser will save the file using a ".pak.zip" extension. This causes problems for the UpdateInstaller.
For example, the Application Server support site may offer an Interim Fix file named "PK12345.pak". A client may download this file using a standard browser on a Windows operating system. The file on the IBM site is correctly named "PK12345.pak", but the browser incorrectly renames the downloaded file to "PK12345.pak.zip".
UpdateInstaller version 220.127.116.11 and later will not allow ".pak.zip" files to be installed
If a maintenance pack file name is incorrectly renamed to ".pak.zip", UpdateInstaller 18.104.22.168 (and later versions) will show an error and not allow the maintenance pack to be installed.
An incorrectly named maintenance pack may cause errors when uninstalling it
Older versions of the version 6.0 and 6.1 UpdateInstaller utility will allow a user to select a ".pak.zip" for installation. (The V7.0 UpdateInstaller has been improved to display an error about this issue.) Following the example above, a user may instruct the updateInstaller to install "PK12345.pak.zip". The UpdateInstaller will proceed with installing the Interim Fix, even though the file name is incorrect. No errors will result from installing a maintenance pack that has an incorrectly-named file, and the installed maintenance pack will be fully functional.
Issues may arise when the UpdateInstaller is eventually instructed to uninstall that fix. Typically, the UpdateInstaller claims that the fix is not available to be uninstalled, or it claims that it is unable to find the backup ".pak" file which is essential to the uninstallation process.
How does the file become incorrectly-named as it is downloaded?
The file format of maintenance package files are implemented in the same manner as "zip" files. Depending on the configuration of the Windows-based internet browser responsible for downloading the file, it is possible that the browser recognizes the maintenance pack file as a zip-type file. With this information in mind, the browser will incorrectly add a ".zip" file name extension to the name of the original file, because the file is assumed to be a standard zip file.
Resolving The Problem
Corrective steps to be taken before installing a maintenance pack
Check the name of the maintenance pack file before installing it. If the file name ends with a ".pak.zip" file name extension, then rename the maintenance pack file to ".pak". In other words, remove the ".zip" file name extension from the file name. Then, install the maintenance pack.
Corrective steps when maintenance pack does not uninstall due to incorrect name
If a maintenance pack file is installed when the original maintenance pack file has an incorrect file name, then the updateInstaller may not be able to uninstall that fix. In addition, if the uninstallation procedure is arranged using a response file in the UpdateInstaller's silent mode, it is possible that the updateInstaller will uninstall a different maintenance pack, because it is unable to find the targeted maintenance pack.
It is simple to determine whether or not a maintenance pack was installed with an incorrect file name. Examine the names of the files in the install_root /properties/version/update/backup directory. If any file name in that directory uses ".pak.zip" as an extension, then the file was installed with the incorrect name and corrective action should be taken.
In order to correct the misnamed file, follow these instructions:
- Navigate to the install_root /properties/version/update/backup directory.
- Rename the maintenance pack file with the incorrect ".pak.zip" file name extension, removing the ".zip". For example, if the file was named PK12345.pak.zip, rename the file to PK12345.pak.
- Make a backup of the maintenanceStack.xml file, then open the original file in a text editor. The maintenanceStack.xml file is located in the same directory as the ".pak" files.
Note: Choose the text editor you use with care! This file has several lines of text which are very long (over 26000 characters on a single line). Some text editors, such as vi, may not save the file correctly due to the long lines.
- Search for all instances of the same ".pak.zip" file in maintenanceStack.xml, and replace any instances of the file name with a ".pak" file name extension. Typically, a maintenance pack file name is present in two lines of that file.
- After saving the file, compare the size of the edited file with the size of the backup. The edited file should only be a few bytes smaller than the backup file. If the edited file is significantly smaller, then it was not saved correctly. Re-do the previous steps and use a different text editor.
- Invoke the updateInstaller and instruct it to uninstall the desired maintenance pack. This time, the UpdateInstaller should find and uninstall the targeted maintenance pack.
UpdateInstaller V22.214.171.124 will prevent installation of .pak.zip files
The UpdateInstaller utility has been updated to prevent files with ".pak.zip" extensions from being installed. However, this change will not automatically fix maintenance packages which were installed when the file names were named incorrectly. As a result, it may be possible to encounter uninstallation issues in the future if some maintenance packs were installed using an older UpdateInstaller version which allowed the incorrect name. Use the procedure above for resolving this issue.
15 June 2018