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I wanted to announce the release of the most requested feature for the PowerShell library for WebSphere MQ SupportPac : support for administering remote queue managers.

I’ve already covered my work on PowerShell for WebSphere MQ at some length on this blog, so I won’t duplicate that here. (If you are interested in a recap, this is a good place to start).

Using PowerShell with remote queue managersWith this latest release, you can now manage queue managers across multiple servers from a single PowerShell window on your local workstation.

You can now write commands which query and/or modify your queues, channels, etc. across multiple queue managers spanning multiple servers on multiple operating systems. All in a single command or line of script.

It currently works with queue managers running on supported Windows and UNIX-based operating systems. (It is not currently possible to administer z/OS queue managers with this, however work on this has begun and should be added in a future release).

Ideas for what can be done with this are welcomed – I’ve put a couple of examples after the break.

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A few weeks ago, Saket posted a link to a very readable document on Data Conversion under WebSphere MQ.

The post has seemed very popular, so I thought I might be helpful to follow it up with some thoughts on diagnosing problems when using data conversion.

The document Saket pointed at is pretty much the definitive reference document, but in this post I will try and add some general observations, and describe a simple technique for diagnosing data conversion problems if things go wrong.

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Last part of a series of posts on working with IBM WebSphere MQ from Windows PowerShell

Over my last four posts, I’ve given an introduction to how to use Windows PowerShell to administer WebSphere MQ, using SupportPac MO74.

For my final post in this series, I want to look at some more advanced uses of PowerShell, focusing on things that cannot be done easily with runmqsc or WebSphere MQ Explorer.

The last four posts have covered the cmdlet basics : New-WMQ, Get-WMQ and Set-WMQ. Where things get interesting is in combining them through the use of the object pipeline.

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Part 4 of a series of posts on working with IBM WebSphere MQ from Windows PowerShell

This week, I’ve been demonstrating how to use Windows PowerShell to administer WebSphere MQ systems, using the support provided by SupportPac MO74.

On Tuesday, I discussed creating new WMQ objects from PowerShell. Today, I want to talk about how to modify existing WebSphere MQ objects.

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Part 3 of a series of posts on working with IBM WebSphere MQ from Windows PowerShell

In my last couple of posts, I’ve been demonstrating the support for using Windows PowerShell to administer WebSphere MQ systems, using SupportPac MO74.

On Monday, I discussed getting WMQ objects with PowerShell. Today, I want to talk in more detail about getting specific objects into PowerShell.

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Part 2 of a series of posts on working with IBM WebSphere MQ from Windows PowerShell

Yesterday, I wrote about the support for using Windows PowerShell to administer WebSphere MQ systems, using the support introduced by SupportPac MO74, and demonstrated how to get your WMQ objects.

Today, I’m going to talk about how to create new WMQ objects.

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Part 1 of a series of posts on working with IBM WebSphere MQ from Windows PowerShell

Windows PowerShell is an object-oriented command line shell and scripting language, available for Windows XP, Windows Vista, and Windows Server 2003.

With the release of SupportPac MO74 (WebSphere MQ – Windows Powershell Library), Windows PowerShell can now be used to administer WebSphere MQ. In the next few posts, I’ll go through a few common WMQ system administration tasks in PowerShell.

For people new to Window PowerShell, I’ve added a few links to good resources for beginners at the end of my post.

Instructions on installing the PowerShell support for WebSphere MQ can be found in the MO74 documentation (pdf). I’ll be writing about what you can do once you’ve done that.

To start with – getting your WMQ objects.

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The changes to Daylight Savings Time (DST) in the United States this year raised questions about the way time is handled by various software programs.

The implications of the DST change for WebSphere MQ are fairly straightforward. In summary, there are no issues with the WMQ runtime (on either the servers or clients) as WebSphere MQ uses UTC and is essentially oblivious to DST. There are some issues surrounding the Java runtime environments supplied with WebSphere MQ. This is all well documented in a TechNote on IBM.com.

Despite this, the DST changes this year were a good reminder of the implications of making changes to the system clock on servers. In this post I will discuss some implications with WebSphere MQ.

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I’ve posted before about setting up WebSphere MQ Explorer as a read-only viewer using setmqaut and MCAUSER ids – a post which has proved quite useful to some readers.

A similar topic which seems to raise questions is using WebSphere MQ Explorer to administer remote queue managers where all server-connection channels are secured using SSL/TLS.

In this post, I will give some background about the issues surrounding using WMQ Explorer with SSL, and outline how it can be used with multiple queue managers.

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In MQSeries 5.2 and previous releases, runmqlsr ran each inbound connection as a new thread within itself. If runmqlsr ran out of resources (memory, threads, file descriptors), then it would not accept any new connections. This massively threaded approach worked well on systems with a limited number of channels, but on very busy systems it was necessary to set up multiple listeners and balance connections across them.

The inetd daemon starts a new amqcrsta process for each inbound connection. There is no chance an amqcrsta responsible for only one channel will run out of resources, so even the busiest of queue managers requires only a single port in inetd. However, this massively unthreaded approach means that busy systems may have hundreds of amqcrsta processess, forcing administrators to increase maxuproc. Inetd has no idea when the queue manager is inactive, so it will start amqcrsta processes even when the queue manager is shut down.

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runmqsc is the command-line tool typically used to adminster local queue managers. It seems that some WebSphere MQ users don’t realise that they can also use runmqsc -w to administer remote queue managers.

Remote administration using runmqsc You need a (default) queue manager on your local workstation so that runmqsc can use it to collect MQSC commands and send them on to the command queues of your remote queue managers.

This lets you do all of your runmqsc administration work from a single point.

The diagram shows an example – note that your local queue manager will need channels going to and from the remote queue managers that you want to administer, to allow the commands to be sent and the replies returned.

Full details on how to do this can be found in Remote administration from a local queue manager in the WebSphere MQ System Administration Guide. It includes further diagrams explaining how the MQSC commands are passed on, and all of the commands that you will need to configure it correctly.

One of the topics which was requested a couple of times last week was about the information in FFST files.

In this post, I will try to give an introduction to these files, and identify some actions which can be taken in the event of an FFST file being generated.

What is FFST?

FFST stands for First Failure Support Technology, and is technology within WebSphere MQ designed to create detailed reports for IBM Service with information about the current state of a part of a queue manager together with historical data.

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I’d like to invite you all to suggest ideas for future blog posts. If there is anything that you would find interesting or useful for us to cover, now would be a good time to let us know.

This could be a HOWTO for something that you think is a little complicated (or even just where something is easy to get wrong).

It could be some background where you think it would be interesting to hear about how a bit of WebSphere MQ works, or why it works the way that it does.

Is there any part of WebSphere MQ where you think we could go into more detail than there currently is in the manuals?

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Update (13/12/2007): The contents of this post have since been largely superseded by the release of PowerShell cmdlets for WebSphere MQ.

A better way to do filtering

A follow-on post from WebSphere MQ scripting using PowerShell – part 2

In hindsight, my approach to filtering was too restrictive (filtering by name only). Instead, it would be better for the function to just return queue objects, and let the user use the built-in functions to filter on them as they want.

Display objects…

  • Choose which attributes you want to be outputted
  • Apply filters – return queues whose parameter(s) match certain filters (supporting complex queries with AND and OR)
  • Sort by a parameter

And do this for local or remote queue managers.

I’m leaving Display-WMQQueues as it is, and have started a new function – Get-WMQQueues – to do this.

This is much much better:

PS-WMQ DALE >  Get-WMQQueues | Select Name, CurrentDepth

Name                                                   CurrentDepth
----                                                   ------------
SYSTEM.ADMIN.ACCOUNTING.QUEUE                                     0
SYSTEM.ADMIN.ACTIVITY.QUEUE                                       0
SYSTEM.ADMIN.CHANNEL.EVENT                                        0
SYSTEM.ADMIN.COMMAND.QUEUE                                        0
SYSTEM.ADMIN.LOGGER.EVENT                                         0
SYSTEM.ADMIN.PERFM.EVENT                                          0
SYSTEM.ADMIN.QMGR.EVENT                                           1
SYSTEM.ADMIN.STATISTICS.QUEUE                                     0
SYSTEM.ADMIN.TRACE.ROUTE.QUEUE                                    0
SYSTEM.AUTH.DATA.QUEUE                                           54
SYSTEM.CHANNEL.INITQ                                              0
SYSTEM.CHANNEL.SYNCQ                                              0
SYSTEM.CICS.INITIATION.QUEUE                                      0
SYSTEM.CLUSTER.COMMAND.QUEUE                                      0
SYSTEM.CLUSTER.REPOSITORY.QUEUE                                   1
SYSTEM.CLUSTER.TRANSMIT.QUEUE                                     0
SYSTEM.DEAD.LETTER.QUEUE                                          0
SYSTEM.DEFAULT.INITIATION.QUEUE                                   0
SYSTEM.DEFAULT.LOCAL.QUEUE                                        0
SYSTEM.PENDING.DATA.QUEUE                                         0
TINY_QUEUE                                                       12

.

PS-WMQ DALE >  Get-WMQQueues | Select Name, CurrentDepth | Where { $_.CurrentDepth -gt 0 }

Name                                                   CurrentDepth
----                                                   ------------
SYSTEM.ADMIN.QMGR.EVENT                                           1
SYSTEM.AUTH.DATA.QUEUE                                           54
SYSTEM.CLUSTER.REPOSITORY.QUEUE                                   1
TINY_QUEUE                                                       12

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