SHIFT-WIKI - Sjoerd Hooft's InFormation Technology
This WIKI is my personal documentation blog. Please enjoy it and feel free to reach out through blue sky if you have a question, remark, improvement or observation. See below for the latest additions, or use the search or tags to browse for content.
Setting ULimit on Red Hat
Summary: How to set uLimits on Red Hat.
Date: Around 2014
Refactor: 29 March 2025: Checked links and formatting.
Most shells like Bash provide control over various resources like the maximum allowable number of open file descriptors or the maximum number of processes available to a user.
Red Hat: Startx and Stopx
Summary: How to change your runlevel on Red Hat from 3 to 5.
Date: Around 2014
Refactor: 29 March 2025: Checked links and formatting.
Using the /etc/inittab file you can modify the default runlevel for your Red Hat box. I usually keep “3” as default. This is an overview of the runlevels in Red Hat:
# Default runlevel. The runlevels used are: # 0 - halt (Do NOT set initdefault to this) # 1 - Single user mode # 2 - Multiuser, without NFS (The same as 3, if you do not have networking) # 3 - Full multiuser mode # 4 - unused # 5 - X11 # 6 - reboot (Do NOT set initdefault to this)
The default is set in the only used line in the file:
id:3:initdefault:
Note that “3” and “5” are the most used runlevels, three being used for console based servers/administrators and five for X11 (graphical) based servers/administrators.
Red Hat SSH Public Key Generator
Summary: How to setup password less login on Red Hat.
Date: Around 2014
Refactor: 29 March 2025: Checked links and formatting.
This is something I done before, SSH Login Without Password is a little howto on automatically login. However Red Hat offers a little utility which makes it even easier to set up automagic logons…
Red Hat Software with Yum
Summary: How to work with YUM to install software on Red Hat.
Date: Around 2014
Refactor: 29 March 2025: Checked links and formatting.
Over the last years Red Hat always had a problem with their software management. Debian had apt, Suse settled on yum but Red Hat tried several software management tools. For now they seem to have settled on yum as well. So this page is about Red Hats implementation of yum. Yum stands for Yellowdog Updater, Modified and works with repositories to manage RPMs which is the format most software on Linux systems is packed in. In this page you'll also find some references to the original rpm command the yum commands are based on.