Well, I just noticed a really weird thing, when you have command line arguments enabled.

Here’s a snippet from my nrpe.cfg:

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dont_blame_nrpe=1
command[check_disk]=/usr/lib/nagios/plugins/check_disk -E -w $ARG1$ -c $ARG2$ -p $ARG3$

Now, if you’d check the free space for the root, it ain’t gonna show any inode percentage (that one isn’t what I’m talking about). But if you have to use bind mounts like I do (Tivoli needs a separate " domain" -- that is a separate mount point for each domain), you might wanna check the free space on the real device, rather than the free space on the bind mount (which is gonna show you the free space of the parent file system - in my case the root fs).

Let’s take a look at what I’m talking about. If you use the check_disk locally like this:

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./check_disk -w 20% -c 10% -p /apache/
DISK OK - free space: /apache 11090 MB (36% inode=36%);| /apache=19629MB;24575;27647;0;30719

Means, everything is okay, you have to pass the extra trailing slash to the –partition argument, as otherwise it would pick up the bind mount at /backup.

Now, if we do the above by means of NRPE, that’s gonna get you a different result. As I showed above, I have the check_disk command in my nrpe.cfg, I also specifically enabled command arguments during compile time.

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./check_nrpe -H nagios.home.barfoo.org -c check_disk -a 20% 5% /apache/
DISK CRITICAL: /apache/ not found

Now, why the hell isn’t it picking up the original mount point of the file system ? Guess why … Because I added -E to the command, because it didn’t use the original mount point but rather the bind mount in /backup. Removing the -E and it picks up the original mount point without any trouble 🤷.