JMX, SNMP, Java, etc...

The first stable release of OpenDS is out! This LDAP Server written in Java can be monitored both through JMX and SNMP.

I recently received a question from a member of the Java community asking for advises on how to implement a trap sending service for a highly multi-threaded application.

Here is an example/test which shows that the SnmpAdaptorServer from Project OpenDMK can be used. The example also allowed me to find a bug.

I am very pleased to announce that we have now a new release of Project OpenDMK which includes the Java DMK SNMP Runtime.

The SNMP Runtime are those API classes in Project OpenDMK that will let you send SNMP requests and implement SNMP agents.

You may have seen an OpenDMK project lingering on java.net for a few weeks: Well, I am pleased to announce that we have pushed a first snapshot of the sources just before JavaOne.

Since Java^TM SE 5.0, the JRE provides a means to manage and monitor the Java Virtual Machine. It comes in two flavors: one is based on the Java Management Extension (JMX^TM), the other is a small SNMP agent that builds upon the Management and Monitoring API of the Java SE platform and exposes the same information through SNMP.

A legitimate question that often arises to newcomers to the JMX and SNMP technologies is:

Which technology should I use to monitor my JVM? JMX, or SNMP?

In this blog I will try to provide some guidance on this subject.

This article comes as a follow-up on a series of articles I have written about SNMP. The series starts with [Simple Is Not Easy] and [What is the JVM SNMP Agent?] and continues with [The Hitchhiker's Guide to SNMP - part I], [II], and [III]. Readers who are not familiar with SNMP are invited to browse these articles first.

In Understanding The Structure Of Management Information (SMI), I have already explained how SNMP tables are defined in SMI and introduced the concepts of Scalar Objects and Columnar Objects, Conceptual Rows and Indexes. I have also shown in an example based on the JVM-MANAGEMENT-MIB how to get a columnar object on a simple SNMP table indexed by a single integer.

In this article, I want to explain how all of this works with multi-indexed tables.

... In a comment to one of my recent blogs, Matthias Ernst asked what's so special about management... Well, as an eager reader of Scott Adams' Dilbert, I could certainly find a few amusing answers. However I doubt they would be found quite apropos... Instead, I'm going to replace the Java Management Extensions into some of their historical perspective.

... In this entry I'm going to outline how you could use the Java DMK 5.1 to send an SNMP trap from within an application deployed in Sun's AppServer. So if you're feeling trapped, come and learn with me how you can send them from within a deployed Web Application ...

... or the Hitchhiker's guide to SNMP - part III ...

Well, what I had really in mind when I started writing this entry, was to demonstrate how to send an SNMP trap from within an application deployed in Sun's AppServer. You might think that was a curious idea - and I may even agree. However, I quickly realized that I wouldn't be able to make my demonstration without first saying a few words about traps in SNMP. So if you're looking at SNMP because the only thing you want to do is sending SNMP notifications - then here are probably a few things you should know if you don't want to... fall in the traps...

...In previous entries I have talked about how to enable JMX traces - and also just any kind of traces which are produced through the java.util.logging APIs. Here is a very short complement to emphasize that the JVM SNMP Agent traces can be enabled likewise...

... or the Hitchhiker's Guide to SNMP, Part-II.

Before I can launch into a blog about understanding the JVM-MANAGEMENT-MIB, I will need to say a few words about SNMP MIBs in general, and more particularly, about how SNMP data is structured. These will be the miscellaneous stops we will make in our hitchhiking journey.

These days, I have been reading - or re-reading, Douglas Adams' Hitchhiker's Guide to the Galaxy. Funny enough, this will be the subject of my SNMP blog today...

In a future blog, I'll tell you more about managing Tiger or Mustang JVMs through SNMP. But for the time being, here are a very few words to clarify what is the Tiger and Mustang JVM SNMP Agent.

Simple is not always Easy, and SNMP is a good example for this. In this blog I will try to broach on a few simple things about SNMP, and I hope you will find this introduction useful.