UPDATE: I’ve written an automated script that performs all the steps in this article in less than 60 seconds. Feel free to follow the steps below if you want full manual control, or download my script to make your life even easier. 🙂 Ubiquiti Networks’ Java-based UniFi Controller software has a […]
Redhat
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If you’re looking for the fastest and easiest way to get DMARC verification working on a RedHat (Fedora, RHEL or CentOS) mail server, I highly recommend OpenDMARC. I’m a bit biased, as I currently maintain the OpenDMARC package in the Fedora and EPEL repositories. This article will help you install the […]
Installing OpenDMARC RPM via Yum with Postfix or Sendmail (for ...
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I’ve previously written a how-to for compiling Postfix from source on a CentOS 5 box. I recently tried following the same steps on a CentOS 6 box, to upgrade from Postfix 2.6.6 which is installed by default. I’m glad to report that the same instructions will work just fine to upgrade […]
Building Postfix 2.10 on RHEL6 / CentOS 6 from Source
Another quick tidbit I learned when one of my CentOS boxes was slow to connect via SSH. Connection happened quickly when I would connect from a box on the same router, but connecting from my home machine caused a delay of 20-30 seconds each time. The fix was uncommenting this […]
SSH slow to connect? Turn UseDNS off
UPDATE 7/11/15: The following procedure will work on RHEL/CentOS 7, 6, and 5 systems to upgrading from those systems’ default versions to Postfix 3.02. CentOS (a non-commercial clone of RedHat’s RHEL) is my server operating system of choice because it’s extremely stable and widely-used. One of the reasons it’s so stable is […]
Building Postfix on RHEL / CentOS from Source
Earlier this year, I wrote a blog post detailing how to set up VNC on a Fedora 12 Box and connect to it from a Windows VNC client securely over the Internet. The original article is here. The steps to setting up VNC on RHEL 5.5 and CentOS 5.5 are […]
Set up VNC on RHEL 5.5 / CentOS 5.5
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I recently noticed that my /boot partition was at 95% full, so I investigated to see what was causing it. Apparently, it was filling up with older versions of the linux kernel as a result of upgrades. Because my system has been very stable, I decided to keep only the […]