A particular virtual machine running Linux CentOS 6.5 had been problematic when it came to yum updates. The result always ended with a PYCURL ERROR 6 – Couldn’t resolve host. After spending way too much time towards resolution, a solution finally came to light. The configuration of the system is a Linux CentOS 6.5 build with two network cards. One…
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Without going into too much detail, for over 30 years the MBR has been the hard drive partition standard, which has a 2TB limit. GPT replaces MBR with one of it’s key benefits, exceeding the 2TB limit. While the fdisk tool is dated, there are several other tools that handle 2TB drives and beyond. gdisk One such tool, is gdisk,…
Read More »Knowing the UUID (“Universally Unique Identifier”) of a device is important in the event of creating a permanent mount point using /etc/fstab. Of course, the name of the device may be used, however, using the UUID is the current trend. There are benefits to this trend. The identifier will likely not be used by anything else so that there will…
Read More »An example of a configuration file with many commented lines is /etc/sysctl.conf. If you wanted to display the contents of the file without the commented lines, the following command may be issued. grep -v ‘^#’ /etc/sysctl.conf However the resulting contents will be displayed with the remaining blank lines. To get around this one of a couple of commands may be…
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Running Oracle’s VirtualBox on a Microsoft Windows 7 desktop to test applications and operating systems has proven to be very productive. As a result of a VPN connection using Citrix, a VirtualBox VM of CentOS 6.5 Linux could not connect to the remote network. After combing through the Internet, a solution is born. I know that there are many variables…
Read More »While perusing through the Internet, I found this site called iF !1 0 “If Not True then False“. I found this write-up on how to install Adobe Reader on one of many different flavors on Linux. I couldn’t pass up on this, since I was in the hunt for Adobe Reader. The process worked great, so here is my slight…
Read More »This should be easy, install Adobe Flash on a Linux operating system to watch Youtube videos in Firefox. After an hour or so fighting with Adobe Flash, through every method I could find on the Internet, I finally found one that worked, the first time! There are many who write of downloading a compressed file and extracting the needed file…
Read More »It was discovered days later that one of my websites was offline displaying only 500 error messages. As it turned out, it was as a result of the .htaccess files. The .htaccess files did not include <IfModule XXXXX> </IfModule> around the directives. Tracking down the offending lines, it was determined that the lines were all part of the mod_headers.c module….
Read More »After searching through several guides, all complete in one way or another, however, not complete enough, I put the pieces together into this guide. This particular configuration is a basic VNC server with two users. After creating the second user, the process can be repeated for additional users. Install the VNC Server yum install tigervnc-server -y Edit the /etc/sysconfig/vncservers file….
Read More »CentOS, Scientific Linux (“SL”), and Oracle Linux are all based on the Red Hat Enterprise Linux (“RHEL”) code base. Though there are differences between them, the similarities are more than not. For whatever the reason, there are documented processes that permit the conversion from one of the aforementioned Linux distros to another. This conversion will document another approach based on…
Read More »GPG keys are stored in the /etc/pki/rpm-gpg directory, as part of the CentOS 6/RHEL 6 install. Looking though the contents of this directory, files like RPM-GPG-KEY-CentOS-release exist. To actually use the key to verify packages, it must be imported. The following command provides the contents of /etc/pki/rpm-gpg ls /etc/pki/rpm-gpg | xargs -n1 basename RPM-GPG-KEY-CentOS-6 RPM-GPG-KEY-CentOS-Debug-6 RPM-GPG-KEY-CentOS-Security-6 RPM-GPG-KEY-CentOS-Testing-6 There are two…
Read More »vsftpd (“Very Secure FTP Daemon”) is an FTP server for Linux and supports PAM (“pluggable authentication modules”). A virtual user cannot login to the Linux system and is considered more secure than using a “real” user whom can login to a Linux system. This guide offers a script that demonstrates yet another way to setup a vsftpd server using PAM…
Read More »Script or batch file writing can be very rewarding, especially when the script written works as planned. What is particularly rewarding is when a shortcut is found that greatly simplifies how the script is written and executed. Here is a couple of shortcuts that I picked up from the Internet. The end result all seem to be the same. This…
Read More »Several years ago, I wrote a set of instructions how to install JBoss on a RHEL / CentOS Linux operating system. Then, the procedure utilized the GUI, mouse clicks, and the terminal. Well, as my comfort level with Linux has grown, so has the instructions into a script. A prerequisite for JBoss is Java JDK. For JBoss 5.1.0.GA, I elected…
Read More »There was a CentOS server where the IP address needed to be changed. Searches through the Internet revealed a series of commands that would do the trick. This script incorporates these commands into a single utility or bash script. This may not be all inclusive, but it did work for me on a CentOS 5.8 server. To use this script,…
Read More »There was a CentOS server where the name needed to be changed. Searches through the Internet revealed a series of commands that would do the trick. This script incorporates these commands into a single utility or bash script. This may not be all inclusive, but it did work for me on a CentOS 5.8 server. To use this script, simply…
Read More »Unlike Windows, Linux can be extremely flexible. Have you ever updated multiple Windows servers. It is a daunting task, even when using an automated approach like WSUS or whatever it is called these days. Linux is easier, however, to log into server, and run a simple command can become time-consuming if there are many servers. I have written a script…
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