Mark Taylor's Blog

Monitoring MQ availability

One of the focus areas for new development in MQ in recent years has been in the area of High Availability and Disaster Recovery. Technologies such as RDQM and Native HA, and automatically managed logfiles, give a range of possibilities for ensuring your messaging systems continue reliably. Alongside the core function, there are also metrics and status information to show more about what is going on. And so the latest updates to the open source monitor programs add collection of some of these recently-added values. This should simplify monitoring MQ availability.

More on Active Directory with MQ on Linux

Several years ago I wrote about using Active Directory (AD) with MQ-specific authentication and authorisation options on a Unix queue manager. In that scenario, AD serves as an LDAP server. The MQ CONNAUTH attribute points at an IDPWLDAP format of AuthInfo object.

There is another approach to using Active Directory with MQ on Linux, where the directory is much more integrated with the operating system. I have seen enough confusion between these two options that I thought it was worth writing something to explain. I’ve had several apparently independent streams of notes on this topic in the last month alone (not to mention the person who seems to have asked everyone they know in the hope of at least one of them giving the answer they want to hear even if it’s wrong).

JMS, JNDI and LDAPS

A recent Idea opened against MQ asked for the ability to store JMS resources using a secure connection to LDAP servers. All the current LDAP support for JMSAdmin and Explorer is documented using the plaintext protocol, but could we use a TLS-protected connection? My first thought was that this was likely to be impossible without changing something – albeit likely small – in the product code. But as I needed to get an LDAP server running locally for other reasons, I thought I’d give it a go to see if my guess was right. It wasn’t; and so here’s how you can do it yourself.

IBM MQ MacOS Toolkit for ARM

MQ has had a developer’s toolkit for MacOS available for a while. Although MacOS is not a fully-supported platform for MQ, the toolkit allows developers to write and test applications on that system, using a client connection to a queue manager.

Apple have gone through one of their periodic hardware-replacement exercises. MacOS machines were based on the x64 architecture for a number of years, but new machines are built on Arm64 (aka Apple Silicon or M1) chips. And so right at the end of 2022 we released a version of the MQ toolkit that can run natively on Arm64 systems. Doing this had some unique challenges, different from ports of the MQ codebase to other machines.

Do we still need application developers?

I read an article at the weekend about the ChatGPT system, which included a link about how it might be useful for programmers. A lot of the recent material on this service has concentrated on its use for generating plausible text – essays and the like. But I thought it might be interesting to take a quick look for myself at the coding capability. How much can be delegated; do we still need application developers?

Spoiler: Yes we do. But it can be useful to look a bit deeper at the good and bad.

Update – Spring Boot and Jakarta Messaging

I wrote recently about the support for Jakarta Messaging that is part of IBM MQ 9.3 and work to integrate it with Spring. At that point, I gave the mq-jms-spring-boot-starter a pre-release version number as there was not a formal version of the Spring Framework and Spring Boot packages. But that changes this week, with the release of Spring Boot 3.0.0. And so there is now a corresponding MQ release of the starter package, also version 3.0.0 to match.

> Task :bootRun

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::                (v3.0.0)

2022-11-25T12:06:23.591Z  INFO 1091972 --- [           main] sample3.Requester                        : Starting Requester using Java 17.0.5 with PID 1091972 (mq-jms-spring/samples/s3.jms3/build/classes/java/main started by metaylor in mq-jms-spring/samples/s3.jms3)
2022-11-25T12:06:23.596Z  INFO 1091972 --- [           main] sample3.Requester                        : No active profile set, falling back to 1 default profile: "default"
...

Aside to the aside: this latest version of the MQ Boot Starter has new optional configuration parameters providing the equivalent of the -D command-line options that you might use for defining location and credentials for TLS keystores. Look at the ibmmq.jks parameters.

Snippet 3 – Converting between MQRFH2 and properties

There are preferred MQI functions for dealing with message properties. But sometimes you may have requirements for converting between MQRFH2 and properties. This post came out of a question posed by a developer on another IBM product. Oddly, it was the same product (though a different person) that prompted a previous Snippet. And I was able to use the same basic framework from that test to demonstrate how simple it can be.

Snippet 2 – Basic MQ Queue Rate monitoring

My previous post was about one small project I got involved with over the last week. This is another one prompted by working with an MQ user, this time to do with metrics. Essentially they had an urgent need to do some basic MQ queue rate monitoring: how many messages were put/got in an interval. More sophisticated observability, whether using a product like Instana, or tools such as these, would be a later exercise. I described what MQ can generate, and what some of the provided sample programs do, but decided it was more interesting to demonstrate it with real running code.

I also think of this as the coding version of the “Yes, And …” rule for Improv. Start with one piece and see where it leads. I ended up with 3 pieces – collect data, format data, display data. Each piece had some utility on its own, but I then thought “Yes, and then what can I do to demonstrate the next phase most effectively.”

Snippet 1 – Building an MQRFH2

Over the last week I’ve been working on some questions sent to me, and several have resulted in writing some test programs and scripts. This post shows the results of one of those exercises, building an MQRFH2 structure from scratch.