MySQL is the most popular open source relational database management system (RDBMS) in the world. MySQL is used by everyone from the simple small business website to the large internet giants like Facebook, Google or Amazon. In fact the contents of this page are even stored within MySQL.
Installing MySQL is a fairly common task for any systems administrator; especially if that administrator is running a standard LAMP stack (Linux, Apache, MySQL & PHP/Python/Perl).
While there are many distributed file systems out there; especially with the rise of cloud & virtual computing. The Network File System or NFS protocol has by far held its title as an easy to use, fast to implement and very efficient distributed file system. In today's article I will be covering how to set up a basic NFS share.
This article will assume that you have already created a file system, if not hop over to this article and then come back for the NFS steps.
The cut command is a Unix/Linux tool used to literally cut text from files and output from other commands. With the cut command a user can take text and output only certain parts of the line.
In my opinion cut is the most under recognized and utilized command in Linux/Unix. This is mostly due to the fact that when most Sysadmins want to cut text from files or standard output many will reach for AWK.
In one of the first posts of this blog I covered some basic SystemTap functionality from an email that I sent to members of my team, but I have always felt that I haven't given SystemTap as thorough of an article as this incredible tool deserves. Today I want to correct that.
For today's article I will show how to compile SystemTap scripts on one server while running the compiled module on a production server without installing debug-info or devel packages in production.
For todays article I wanted to put together a quick little cheat sheet for some GNU find command examples.
Some of these commands will be basic some will be more advanced, but they all will be useful. As a caveat some commands don't work in all Unix environments and this is especially true with older releases. If you find yourself in one of those situations there is a way to make the find command work you will just need to use different methods like the -exec flag.
Access Control Lists aka ACL's are one of those obscure Linux tools that isn't used every day; and if you find yourself using ACL's every day than you probably have a very complicated Linux environment.
A few years ago I had an engineer tell me “Any thing you want to solve with ACL's can be solved with standard unix permissions” and while he may have just been justifying why he didn't know ACL's very well.
One of the primary tricks in my sysadmin bag-o-tricks is Input/Output Redirection; I have found that while many people use Shell I/O Redirection throughout their day not everyone fully understands why and how it works.
The Input and Output In the Unix environment there is always 3 streams open stdin, stdout, & stderr; these special streams are used for interacting with the user input and program output within the Unix/Linux shell environment.
While it is getting more common for companies to allow their IT staff to choose their own OS not every company allows this. In fact most companies require their IT staff to use Windows, as Windows has historically been the dominate OS for the business world. While I personally believe it is easier to administer Linux/Unix servers using a Linux desktop this doesn't mean that I get to be the exception to the rule; sometimes I have had to use a Windows desktop.
Cron is a time based scheduled task daemon that runs on most common Unix/Linux distributions. Because cronjobs are time based sometimes it is necessary to validate that the job ran at the scheduled time. Sometimes people will configure a cron to send the output of the script to a user via system mail or redirect the output to a file; however not all crons are setup the same and many times they may be configured to send output to /dev/null hindering any ability to validate the job ran.
While I normally am able to avoid the desktop support role there is one person out there who guilts err.. convinces me to help her out. My mom.
I'm not going to sit here and bash my moms computer skills, in all actuality she is pretty good with a computer. In the past she figured out how to add a printer and print something with Ubuntu by herself.
The problem is my mom is a Windows user and she is the typical user who receives questionable emails and goes to certain sites that promise you win things but only infect your OS with spyware.