JDK fixes for WebSphere Application Server

Answer

A JDK(Java Development Toolkit) is a base component of WebSphere Application Server that is installed automatically when WebSphere Application Server is first installed. WebSphere Application Server depends on the JDK and as such they are inseparable.

It is important to note the following:

1. For WebSphere Application Server V8 and above, the fixpacks contain both WebSphere and JDK fixes combined as part of a single install zip file. An install of this fixpack upgrades both Webphere and JDK.
   
   
2. For WebSphere Application Server V7 and below the fixes are maintained separately. The maintenance of WebSphere Application Server consists of two separate updates:
   
   
1. WebSphere Application Server
2. JDK

Thus the updates for JDK and WebSphere Application Server V7 (and below) are independent of each other and must be downloaded and installed as separate packages. The order of the update for JDK is not relevant - it can be installed before or after WebSphere Application Server fix pack.

It is the best practice to upgrade the JDK component when upgrading the WebSphere Application Server fix pack as it may frequently provide the quickest path to resolution of potential problems. There are many critical situations that have arisen from clients running an older version of JDK which have been resolved by simply updating the JDK.

A strategy to update both WebSphere Application Server and the JDK at the same time can not only save you from production outages that are costly, frustrating and time consuming but also provide an added benefit of testing both the upgrades of WebSphere Application Server and the JDK at the same time.

How do I keep up-to-date with the JDK?

For WebSphere Application Server V8 and higher both JDK and WebSphere Application Server updates are part of a single bundle. Thus latest fixpack of WebSphere Application Server will also update your JDK to the latest. See link below for latest available fixpack.

For WebSphere Application Server version V7 and below you should down load the latest JDK fix pack and install it using IBM WebSphere's UpdateInstaller - just like an install of WebSphere Application Server fix pack update. The link to the latest available JDK is under "Java SDK fix pack download page" in the latest WebSphere fixpacks.

The following link provides latest WebSphere fixpacks:
http://www-01.ibm.com/support/docview.wss?uid=swg27009661


How do I obtain fixes for problems discovered with the JDK?

The only supported JDK for use with WebSphere Application Server is the one that is specifically packaged for and supplied by IBM for WebSphere Application Server. JDK from any other source is not supported. The greatest stability with the least risk for clients running WebSphere Application Server can be achieved by employing the latest available JDK with the latest operating system patches. It is thus required to be at the latest operating system patches that are relevant for correct execution of Java.

The software implementation of JDK runtime for WebSphere Application Server on AIX, Linux and Windows is developed, maintained and packaged by IBM. To obtain fixes for these platforms an iFix request form will be provided by WebSphere Application Server support team that needs to be completed prior to obtaining the fix. Fixes will only be supplied on top of the latest SR (SRn) or the prior SR(SRn-1).

The JDK runtime for WebSphere Application Server on Solaris and HP-UX is re-packaged by IBM to distribute IBM componentry necessary for WebSphere. The JDKs of WebSphere Application Server on Solaris and HP-UX are developed and maintained by the vendors of Solaris and HP-UX respectively. Obtaining fixes for these JDKs requires complying with their service processes, specifically:

1. Any fix work will only occur with the latest available level of their codebases and
2. All fixes developed (with IBM support) require customer verification before they become available in a supported, generally available version of a JDK service release.

Here are the steps that WebSphere Application Server support team will follow to obtain the fixes from vendors of Solaris and HP-UX:

1. If you are not already at the latest JDK level then you will be required to upgrade to the latest level of the JDK available for WebSphere Application Server. It is also a requirement as stated earlier to be on the latest OS patches.
   NOTE: step #1 is most important and it is required before taking further actions towards the resolution of your problem.
   
   
2. If the problem still exists then IBM Java Level 3 team will contact the vendor's (Solaris or HP-UX) development team to review the problem. The vendors will provide the latest level of code stream under development to IBM. IBM will then package this code for WSAS and provide it as an installable image for WebSphere Application Server.
   
   
3. If the problem still exists with latest code stream provided in #2 then the vendors will provide diagnostic builds or test fixes via appropriate code changes iteratively for further evaluation until the problem is resolved. Please note this could take several iterations before reaching a final solution.
   
   
4. A final supported version of the JDK fix will only be released after the verification of the test fix in #3 above. It will then usually be released in the vendor's next service release.

As seen above there could be several iterations before a final fix can be obtained. By staying current with the latest JDK level it is possible to reduce the time to resolution by completely avoiding step #1.