Monitoring Blog
Release announcements, technical guides and monitoring insights from the ConSol team.
Jmx4perl Configuration Files
Monday, December 07, 2009 in Insights
When you have already used jmx4perl you probably have remarked that the argument list can be quite lengthy, often due to the verbose JMX URLs. This gets even worse with jmx4perl’s forthcoming proxy mode. Luckily, since version 0.36 it knows about configuration files which are the topic of this post. Configuration files can be used for the command line tool jmx4perl and from within the module JMX::Jmx4Perl (it is not yet supported for the Nagios Plugin check_jmx4perl. Please leave me a comment if you think this would be a sensible addition). Within a configuration file various parameters can be specified, mostly URLs (target, proxy) and credentials for connecting to those URLs. The syntax is in Apache HTTP-server style (as described in Config::General) and can contain multiple <Server> …
Configuring remote JMX access for Weblogic Server
Wednesday, December 02, 2009 in Insights
In our series of articles about configuring remote JMX access for the jolokia proxy mode, this article tackles how to enable JMX remoting for Weblogic Server 9 and 10. It is not specific to jmx4perl and explains several different setups and possible problems. But before we start, kudos to this excellent blog post and Weblogic’s own documentation which helped me quite a lot during my journey through the depth of Weblogic JMX export. As worked out in a previous post JBoss is a bit of a mess when it to comes to export the JDK’s PlatfomMBeanServer. As it turns out for Weblogic things are not much easier (but there are ‘workarounds’). Weblogic even doubles the number of available MBeanServers to four. MBean Servers in Weblogic Weblogic comes with three own MBeanServers, which are exported via …
Endlich...check_hpasm Release 4.0 ist fertig
Tuesday, December 01, 2009 in Insights
Statt zwei Wochen hat das Redesign von check_hpasm nun doch zwei Monate gedauert, aber dafür ist das Plugin für künftige Erweiterungen bestens gerüstet. Hinzugekommen ist die Unterstützung der neuen G6-Proliants und die Fähigkeit, auch HP BladeCenter (wenn auch nicht so detailliert) und HP Storage-Systeme überwachen zu können. Es wurden auch ein paar Verbesserungen an der (nicht ganz einfachen) Erkennung der Speichermodule vorgenommen. Bei einigen Anwendern dürften jetzt defekte Riegel ans Tageslicht kommen, deren Zustand sich mit der 3.x-Version nicht feststellen liess. Zu beachten ist, dass sich die Blacklisting-Kürzel teilweise geändert haben. Das neue Format findet man unter der Überschrift "Blacklisting". Im Gegensatz zu den Pre-Releases braucht man das Perl-Modul Nagios::Plugin nicht …
check_nagios_external_commands
Monday, November 30, 2009 in Insights
Nagios installations which rely on working external commands should have a check which verifys that external commands are really working. This plugins sends a test command and checks the logfile if that command occurs. $ check_nagios_external_commands -t 120 -p /usr/local/nagios/var/rw/nagios.cmd \ -l /usr/local/nagios/var/nagios.log WARNING - command took 23s|command_write=0.85s command_read=22s check_nagios_external_commands_0.1.tar
Access restrictions for jmx4perl
Saturday, November 28, 2009 in Insights
jmx4perl knows since some time how to restrict access to the agent (and soon proxy) servlet based on various criteria. However, this feature is unfortunately not yet well documented and a little bit hidden. This blog describes the nifty details and future roadmap. Access restrictions are described within an XML-document which is included in the agent servlet j4p.war. The out-of-the-stock j4p.war doesn’t include any restrictions. There are two ways for adding j4p-access.xml to the servlet. The agent servlet can be easily rebuild out of the source distribution. The only prerequisites building the agent servlet are a JDK (>= 1.5) and a ant (the make in the Java world) installation: Download the source distribution from CPAN and extract it. Go into the agent sub-directory Copy …
Setting up JBoss for remote JMX
Monday, November 23, 2009 in Insights
As described in the last post jolokia can be operated in a so called agentless mode. For this to work, the target java server must be prepared for accepting remote JMX connections as described in JSR-160. Unfortunately, this setup is not really standardized and specific to the Java JDK in use and the application server itself. In this post we concentrate on how to setup JMX remoting for JBoss. Setting up remote JMX Setting up JMX remoting depends on the Java virtual machine you are using. Since the Sun JDK is by far the most common Java VM in use, I’m assuming you are running with a Sun JDK 1.5 or 1.6. Please refer to this article for detailed instructions for how to enable JMX remoting for Sun JDK 1.5. JMX remoting is enabled by setting certain Java environment variables. For JBoss, you …
Jmx4Perl without agent servlet
Friday, November 20, 2009 in Insights
Big news around: jmx4perl supports now an agentless mode in which the target platform can be monitored without installing the j4p agent servlet. This works by using j4p.war as a JMX Proxy, which translates our JSON/HTTP protocol on the frontside to JSR-160 JMX remote requests on the backend and vice versa. Version 0.50 has been submitted to CPAN. If you want to try out the proxy mode, here is a recipe to set it up. In this example I use JBoss 4.2.3, but you are encouraged to try it out for a different application server of your choice (in which case I’m really keen to know your feedback ;-) Download jmx4perl-0.50.tar.gz and install it as usual Install Jetty or Tomcat by simply extracting it Copy j4p.war from the agent/ directory into Jetty/Tomcat’s webapp directory Startup Jetty/Tomcat …
Heartbeat-Cluster OCF-Agent für ndo2db
Friday, November 13, 2009 in Insights
Betreibt man eine hochverfügbare Nagios-Installation mit dem Heartbeat-Cluster, so benötigt man für die einzelnen Softwarekomponenten (Resourcen genannt) Agenten, die sich um Start, Stop und Überwachung derselben kümmern. Folgendes Script ermöglicht die Einbindung des NDO2DB-Daemons in so einen Cluster. Dazu muss man es nur nach /usr/lib/ocf/resource.d/<heartbeat oder ein eigener Provider>/ndo2db kopieren. Download: ndo2db
jmx4perl 0.36 and 0.40_1 released
Tuesday, November 10, 2009 in Insights
Last week a minor update for jmx4perl was released. Beside bugfixes and code cleanup, version 0.36 includes: A way to restrict agent acces to certain IPs or networks Experimental support for a JDK 1.4 agent Support for configuration files in order to alias server configuration parameters But wait, there is more … ;-) Version 0.40 has been released as a developer release which contains rather big changes concerning the agent servlet. In addition to the usual GET HTTP request, which encodes a JMX request completely within the URL it now allows for POST HTTP requests containing a JSON representation of the JMX request. This way, jmx4perl is now also able to process bulk requests, i.e. multiple requests as one. For pure Perl users, this extension works transparently and is reflected only in a …
check_mssql_health 1.5.3
Monday, November 02, 2009 in Insights
Eine neue Version von check_mssql_health ist soeben erschienen. In erster Linie wurde ein Bug im Mode database-free beseitigt, der zu ungenauen bzw. falschen Ergebnissen führte, wenn der freie Plattenplatz knapp wurde. Daneben wurde der neue Mode database-backup-age eingeführt, mit dem sich überwachen lässt, wie lange der Zeitpunkt des letzten Backups zurückliegt. Dabei handelt es sich um die Funktionalität, die in einem der letzten Blogs unter der Überschrift "MS SQL Server Backups überwachen mit check_mssql_health" als Erweiterung vorgestellt wurde. Dieses Zusatzmodul wurde jetzt in den Plugin-Kern integriert.