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:

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.

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.

We have received a lot of emails with questions about Network Appliance (NetApp) devices and being able to use some advanced tools. We will periodically explore the standard and advanced tools, in future articles. To start with, it seemed to make sense to explore what commands were available via the advanced tools.

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.

It is common to setup a phone switch with multiple T1s, each purposed with a special use. An example of such a configuration might be to have one used for local calls, and one for long-distance calls. To test the route that the call will make through the switch, you can run a couple commands and get a great deal of information.

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.

The Avaya Audix VoiceMail system is fairly common in today's VoIP environments. I recently had a user report that they were unable to contact the Audix server. When the user tried dialing the Audix extension, it just kept ringing and ringing.

To check on the status of the channels in use, I used my browser to login to the server. I did the following:

It is good practice to check on the health and capactiy of your phone system. Ideally you should regularly check to see how many of your T1 channels are in use. On a typical T1 PRI, you have 23 voice channels available for calls. To view the number of channels in use....

If you are having outbound call problems, it is recommended that you check your equipment before calling the phone carrier. It is likely that your phone carrier will try to blame your equipment, and you need to make sure you've done your homework. You can check the health of your T1 PRI on an Avaya Definity gateway by doing the following...