Installing the Nagios NRPE Server on a Raspberry Pi

Below are the steps to install the Nagios NRPE server on a Raspberry Pi. The configuration of the Nagios Server side are outside the scope of what we are trying to do here. This also assumes that you are running Raspbian on your Raspberry Pi.

First, we’ll want to make sure we have the latest cache of the repos.

sudo apt-get update

Next, we can go ahead and install the Nagios NRPE server on the Raspberry Pi:

sudo apt-get install nagios-nrpe-server

It will give you a list of dependencies it will install, and then ask you if you want to proceed. You can just type “y” and press ENTER.

Do you want to continue [Y/n]?

You’ll notice that it should have also installed a lot of the common Nagios plugins, which you’ll need for monitoring this host.

We will now want to configure the NRPE service. Go ahead and edit the config file using your preferred editor:

sudo vi /etc/nagios/nrpe.cfg

At a minimum, you’ll probably want to edit the “allowed_hosts” parameter, to include the IP of your Nagios Server.

Once the file is updated and saved, we’ll need to restart the NRPE service to read the changes.

sudo service nagios-nrpe-server restart

You should now be all set with NRPE running on the Raspberry Pi, and able to configure the Nagios Server to poll it for monitoring.

Plex Media Server Not Starting on CentOS 6

Today I updated my Plex Media Server, but it wouldn't restart! I didn't see any errors on the command-line or in any of the logs. It was silently failing with no hints to the problem.

I looked at the init script and tracked down how to manually attempt to start Plex. When starting it manually, I found it was giving an error of:

error while loading shared libraries:

Configuring Roundcube Webmail for Multiple Domains

There are a lot of different ways to configure Roundcube Webmail to handle multiple domains. In an effort to have a similar experience to my legacy webmail system, I wanted Roundcube to have a drop-down list of domains/servers to login to.

Configuring a Static IP for a Raspberry Pi running Raspbian

The recommend OS for the Raspberry Pi devices is typically Raspbian.
By default a Raspbian install starts with the nework configured via DHCP. Raspbian is based on Debian, and does things a little differently than their cousins Fedora/RedHat. Instead of configuring resolv.conf directly, it needs to be included with the interfaces configuration file.

How to Parse DMARC Reports via IMAP

After my recent post about "How to Parse DMARC Reports", I decided to find a way to directly query an IMAP folder to parse reports. I have started with John Levine's rddmarc script, and modified it to connect to an IMAP server.

In the process of working on this, I also discovered that some receivers are sending their DMARC reports as multipart attachments. The original rddmarc script did not seem to handle this condition well, so I added this capability as well.

How to Parse DMARC Reports

The current buzz in the e-mail industry, is around Domain-based Message Authentication, Reporting & Conformance, commonly referred to as: DMARC. DMARC pulls together SPF and DKIM, into a method to try to stop spam and keep people from abusing your brand/domain. One of the added benefits of DMARC, is that receivers are able to report back to the domain owner, the disposition of messages being sent into their environment. Gmail is currently one of the few receivers providing these reports back, but hopefully adoption will be growing soon.

DMARC Web Reporting Tool

After parsing your DMARC results, you will need an easy way to review the results. I've put together a VERY basic PHP script that can be used for display DMARC report results.

Deploy DKIM Milter for Multiple Domains on CentOS 5 with Sendmail

I decided that it was time to learn about DKIM and deploy on my servers. As a habit, I typically run CentOS 5 and Sendmail since it is the default MTA.

To install the DKIM-milter, I would recommend using the packages provided by the "Extra Packages for Enterprise Linux (EPEL)"; a Fedora Project. Once you have the EPEL Repo setup on your system, you can:

Monitor Your Site on Google Safe Browsing with Nagios

Today a friend of mine had his site hacked, and when browsing to the site with Google Chrome it warned me that the site was infected with malicious code. Awhile back I provided an article regarding Monitor MythTV with Nagios. I figured I could write a Nagios check to see if a given site was listed on the Google Safe Browsing list.

Trace a Call to an Extension on an Avaya Definity

It is sometimes difficult to figure out why a certain call is being call is being routed a certain way, or behaving unexpectedly. As a troubleshooting step, it can be helpful to peform call traces.

Syndicate content