Sam Pointer

I recently tried out Nic le Roux’s sched_downtime Perl script as a quick punt to getting recurring Nagios downtime working. Cool script, and it beats having to hand-roll something to append the the nagios.cmd command pipe file by hand. Why reinvent the wheel, right?

There’s a small problem with the script, on my 3.0.6 install of Nagios anyway, whereby the command string that is produced is missing a field, leading to the commands not being acted upon. See:

[1264767246] EXTERNAL COMMAND: SCHEDULE_SVC_DOWNTIME;sam;ssh;1264767600;1264768200;1;600;Sam;Testing service recurring scheduled downtime
[1264771220] EXTERNAL COMMAND: SCHEDULE_SVC_DOWNTIME;sam;ssh;1264771800;1264772400;1;0;600;Sam;Testing service recurring scheduled downtime

See the extra field there? The same is true of host scheduled downtime too. If we check the documentation we can see that the extra field is a ‘trigger_id’.

I’ve created a patch that will enable you to use the script against Nagios versions that expect the 3.x format command strings. My patch deals with the possibility of being able to trigger downtime based on other downtime events by conveniently ignoring it, and hardcoding a zero in that field. I didn’t need it, sorry!

 

This post documents my attempt to get PAR and PAR::Packer running under ActiveState Perl on Windows XP SP3 in order to produce a native Windows executable of a Perl script. We use this to compile some custom cross-platform Nagios modules.

The first key thing is to start with ActiveState build 5.10.0.1004 or greater, as this fixes a YAML parsing problem that prevents CPAN modules from being installed. PAR::Packer isn’t in the ActiveState repository, so we’ll need to use CPAN to get some of the bits that we need.

• ActiveState Perl

Once that’s done its thing, you’ll need to grab a copy of Microsoft Nmake 1.5. Running the .exe will unpack nmake.exe, nmake.err and README.TXT into the root of C:. You will need to copy these three files into c:\perl\bin. Nmake is needed to build CPAN modules.

• Nmake 1.5

At this point I used the ActiveState Perl Package Manager to update all of the modules that had updates, also electing to install any packages required to satisfy dependencies.

Next, I used CPANPLUS to install PAR::Packer, as it’s not in the default ActiveState repository used by the Perl Package Manager. From a prompt:

cpanp
...
i PAR::Packer

confirming the installation of the module dependencies. At this point you might want to put the kettle on as there are a bunch of build/test tasks to run whilst all of the modules install.

It was here that the build failed for me. I realised I’d neglected to install MinGW to do the native binary compliation, unless you’ve got Microsoft Visual Studio 6.0 that is - in which case it is preferred.

• MinGW one-click installer

You will need to manually select to install the g++ component, along with the base install. Once this is installed, add C:\MinGW\bin (assuming you took the defaults) to your system %PATH%, close and reopen your command prompt to get the new value, and re-try the cpanp steps.

This should give you a completed installation. Just to check:

pp
...
Set up gcc environment - 3.4.5 (mingw-vista special r3)
C:\Perl\site\bin/pp: No input files specified

Ready to go.

pp -o myprogram.exe myprogram.pl