Technical support knowledge for Application Integration Middleware including WebSphere, CICS, BPM, MQ, Broker, IIB, ODM, DataPower, Mobile, Appliances, and more! Following the IBM Social Computing Guidelines - Steve Webb, Joseph Lam
Upon investigation of a WebSphere Application Server performance issue, you may find that the poor performance correlates with long classloader unload times. To check if this is indeed a problem, enable verbose GC and note the times of poor performance. Then correlate the times of poor performance to the time stamps in the verbose GC data:
Example of long class unload time as seen in the verbose GC output (default log is the native_stderr.log in WebSphere):
This time around, I have a requirement to deploy IBM HTTP Server (IHS) and the WebSphere Plugin to route traffic to WebSphere Application Server (WAS). So far, so good. However, the difference is that, this time, I'm NOT leveraging the power of WAS Network Deployment ( WAS ND ). There are no clusters here. Equally, the two instances of WAS are completely self-contained. For my proof of concept, I've got a single set of WAS binaries ( I am using WAS 22.214.171.124 ) with a pair of standard profiles, AppSrv01 and AppSrv02.... [More]
High Availability (HA) Manager is a framework that allows singleton services to make themselves highly available. Transaction Log Recovery is one of the HA Manager users.
Every WebSphere Application Server process is a member of a HA Manager DCS CoreGroup. During server (cluster member) startup, transaction manager and other server components will also get started. Transaction Manager should have exclusive ownership of its transaction recovery log file before it can initialize successfully. HA... [More]
The requirement is to create a clustered WebSphere MQ (WMQ) infrastructure, and then send messages to an application, known as a Message Driven Bean, deployed onto WebSphere Application Server (WAS).
The next step will be to create a more sophisticated application that can send and receive messages to/from WebSphere MQ, most likely leveraging the JavaEE Service Component Architecture.
In this scenario, I will create a pair of WMQ Queue Managers, each on a separate OS ( Red Hat VM ), one representing... [More]
To compress content before it is delivered to the client you can use Apache Module mod_deflate
To compress text/html text/plain text/xml text/css and js files in the IBM HTTP Server, add the below 2 lines to httpd.conf:
LoadModule deflate_module modules/mod_deflate.so
and restart IBM HTTP Server.
To see what files a browser is getting as compressed, in Firefox, you can create a shortcut... [More]
Recently, we encountered a very interesting problem using a mediation flow to integrate IBM Business Process Manager and another system.
The topology for this problem is IBM Business Process Manager -> WebSphere Enterprise Service Bus -> another system
If you define the same business object structure in IBM Process Designer and IBM Integration Designer, the automatically generated WSDL that is based on these business objects are different. For example. you define the following business object structure in IBM... [More]
With an increasing amount of stack products being available and used with WebSphere Application Server on z/OS, we're starting to see EC3 timeouts of different varieties that are caused by Mbean long waits or deadlocks. An initial review of the dump and reason code may produce what looks like a common timeout, like HTTP or EJB. But closer inspection of an SVC dump or javacore could reveal that the thread that took the timeout was actually waiting on an internal Mbean request.
In general, Mbean requests flow... [More]
From MQ 126.96.36.199 onwards, the dreaded AMQ9633 "bad certificate" error message was enhanced with some additional information to help you understand which certificate was rejected and why. This is the most common error seen for SSL/TLS handshake errors and so I'd like to explain how to use the new information to understand the cause of the error.
Example AMQ9633 error
Below is an example of the new style of message with the new section highlighted in bold text, taken from a queue manager error log:
The WebSphere L2 Support team handles its fair share of WebSphere Application Server performance analysis. Often it appears as though the Monitoring Agent (that thing that reports whether the system is behaving - or not) is the problem itself. The truth is, the more problems that the agent has to report, the more noise the agent is going to interject into the diagnostic data. It's a vicious cycle.
One of the common agents that are encountered is Wily. Like any performance monitoring tool, Wily can introduce a... [More]
List of firewall ports that must be open for communication between the deployment manager, nodeagent, and Application Server
It's very important to know the ports that should be opened in the firewall for proper communication between deployment manager, nodeagent, and application servers. Follow the below steps to achieve this task.
Find the port numbers in the serverindex.xml file or from the ISC (Integrated Solution Console)
The serverindex.xml file can be found under the... [More]
Occasionally when reviewing a heapdump that was generated from an out of memory event, the largest consumer of heap memory may consume slightly more memory than the other objects. Because of this, WebSphere users and moderators may incorrectly accuse the largest heap consumer as a memory leak.
If a Java™ heap is sized too small, an out of memory error will occur regardless if a memory leak exists. The leak suspect shown in IBM HeapAnalyzer or Memory Analyzer (MAT) will show a java object... [More]
The transaction timeout value can be set in the application component or in the administrative console for WebSphere Application Server (WAS). If the application component does not specifically set its own transaction timeout, WAS will timeout a transaction according to the 'Total transaction lifetime timeout' property. This property is the default maximum time allotted for a transaction to complete before it is timed out. If completion processing is not started on the transaction before this timeout value is reached, it... [More]
PCF messages are unique within WebSphere MQ because they help to solve problems like remotely administering an MQ network as they grow and thus become more complex. Remote administration through their use helps to centralize task execution and can help with resource management, object manipulation, and performance monitoring just to name a few.
The product documentation in the IBM Knowledge Center provides some great reference material on the topic. Its chapters contain detailed information on these messages and... [More]
If there is no cell default certificate SSL setting, then JSSE will pick one.
To set a default do the following:
In your Deployment Manager environment, logon to the Admin console.
Go to Security --> SSL certificates and key management --> manage endpoint security configurations.
Under inbound, select the entry that contains your cell name followed by "(CellDefaultSSLSettings,)".
Next click on update certificate alias list under SSL configuration.
(post by Alexander Frank)
Can applications talk? Can computers talk? Can humans talk? Yes? OK. Let us agree on that one. At least most of us have the ability to talk. Why do we talk? Well, one definition of talking, is “to communicate or exchange ideas, information, etc. by speaking.” Great! Now we are faced with yet another word, speaking. Speaking is “articulating sounds with the ordinary voice.” So, without getting lost in definitions, talking involves exchange of... [More]
(post by Alexander Frank)
There are so many influencing factors and levels of communication. Just because you said it does not mean whoever you are speaking to understood it. Have you ever been in a crowded and noisy place, trying to talk to a friend? What happens to me sometimes is that I do not hear what my friend said. So I just smile and hope it was not a question. Not the perfect way, I know. But if you have been screaming the whole time and your throat already hurts, you just go for the... [More]
The common question
I've been asked multiple times through various means, "How can I tell if my iFix is installable as-is when I upgrade WebSphere Application Server (WAS) to a newer fix pack level?" The answer, as it is to so many things, is "it depends." The manual method is not necessarily difficult, but may be a bit tedious if you have a lot of iFixes to consider. The automatic method is sometimes simpler and can be performed through the Installation Manager (IM) GUI or command line tool, depending... [More]
When WebSphere Application Server is running a transaction, the transaction information is written to the tranlog directory to log1 & log2. The resources required for that transaction (database name, user, password, etc) are recorded in the partnerlog directory to it's log1 & log2. When a transaction completes, the transaction information is garbage collected from the logs. If the application server should abend or be forced off mid-transaction, such that a transaction does not complete, then on subsequent server... [More]
I have just spent the last month writing my first ever IBM Redbooks publication: IBM MQ V8 Features and Enhancements . And an interesting experience it was too!
A group of eight of us assembled from around the world (UK/USA/Mexico) at IBM Hursley in the South of the UK for an intensive four week period of writing, and experimentation. We had done a large amount of preparation beforehand, so we already knew what chapters we were going to write and who was going to write what. We had also had training in the... [More]
We've probably all see a hung JVM at one time or another and chances are you've figured this out in one of two was if you're dealing with WebSphere Application Server: 1. the users are complaining that the browser just “spins” and never returns a web page, or 2. you've noticed output in the WebSphere logs (SystemOut.log) that indicate potentially hung threads. For the purposes of this discussion, we'll focus on the latter method.
WebSphere Application Server provides a feature that... [More]