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.

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.

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.

In an effort to be a good "net-citizen", I decided to configure my domains with DMARC record. It was great, because within 24hrs, I started to receive reports from Google/Gmail with DKIM and SPF related information for my domains. Now I needed to figure out how to actually process these XML reports into something useful and readable.

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.

Recently I have been using a proprietary application which stores IP address in a hex notation. Unfortunately this hex address is far from useful when doing troubleshooting or diagnosing. Originally I was told to pull each two hex digits and convert them via the calculator of my operating system. This was very manual and annoying to say the least. I decided to write a short script with the limited tools available on the machine I had to use for this purpose. While I am sure there would be a more elegant way of doing this, it gets the job done.

One of the great advantages of using Drupal for website content, is the enormous amount of modules available to enhance end-user experiences. In general I try to use the CVS versions of Drupal, for easy upgrade capabilities. In the same way I prefer to use CVS to check-out the modules that I add-on.

I have written a simple script to automate the download of modules from CVS into the site. The script lives outside the Drupal folder, to keep the Drupal folder clean.

I have been using MythTV (http://www.mythtv.org) for several years, and recently realized I should better monitor the health of the system. Nagios (http://www.nagios.org) is currently deployed to monitor most of the components (i.e. memory, cpu, disk usage, processes, etc). However, it is not uncommon for issues to arise, which may cause problems with obtaining the Guide Data. I have a desire to create a more thorough system, but have temporarily made a simple check for how many days of guide data is currently available.

When doing any moderate to advanced networking, you are likely to have to deal with subnetting. While some people have an ability to do the binary math in their head to figure out the correct subnet-mask, I prefer to use a tool to give me the answer. I have used “ipcalc” on my FreeBSD machines for years, to give me the answers to my subnetting problems. I recently tried to use the ipcalc tool on my Fedora machine and found it to be completely different. Apparently RedHat has developed their own ipcalc tool, with the same name as another project. It is not terribly surprising that this situation could have happened, as both projects attempt to provide similar information.

In my humble opinion the RedHat ipcalc is not nearly as informative as the tool created by Krischan Jodies found at: http://jodies.de/ipcalc At their site they provide an online version, for quick access. If you want to download the tool for use on a Linux/Unix machine, it can be found at: http://jodies.de/ipcalc-archive/

When creating user accounts on servers and devices, it is important to use strong passwords that will be difficult to guess or crack. It is often preferred to at least create accounts with a random password, and allow the user to change it to something they can remember. A great Linux tool for creating passwords is “pwgen”. Most distributions have “pwgen” available in their package management resources. To install the tool on Fedora, use: