You might save some time and have a little fun by putting some aliases and functions in your .bashrc file. You can put functions or aliases in .bash_profile or .bashrc in your home directory. But by using .bashrc instead of .bash_profile, they’ll be read in not only when you log in, but whenever you start […]
Aliases & Functions in Bash
Kernel recompile
Before you do anything else, make sure you have a way to boot the OS. Make a bootdisk and test it. Get the source for the kernel and put it in /usr/src. cd /usr/src tar -xzf <kernel source file name> The kernel source lives in /usr/src/linux. Linux is usually a symbolic link to the source […]
Determine version of running kernel
uname -a You’ll see something like this: Linux u-1.signalq.com 2.4.6 #2 SMP Sat Jul 14 09:02:08 PDT 2001 i686 unknown
Using RPM
One task that we often do is remove rpms that are installed by default. In this example, we will find out what rpm apache uses and we will uninstall it. What we need to do is find the name of the apache package: [root@srv-3 RPMS]# rpm -qa | grep apache apache-1.3.19-5 [root@srv-3 RPMS]# So, we […]
Linux From Scratch Version 3.0 Released
For those of you who wish to learn more about how a GNU/Linux system is put together, or if you want to have more control over your GNU/Linux system, check out Linux From Scratch (LFS). The commands for building a system from scratch are provided, as well as step-by-step instructions and explanations. Simply download the […]
Automated creation of GNU/Linux systems w/ XML spec file
I’ve mentioned Linux From Scratch in previous articles. I’ve discovered another tool related to this project that rocks called ALFS, or Automatic Linux From Scratch. ALFS puts all of the specifications for compiling a linux system into an XML document and generates most of a Linux From Scratch system automatically. There are a couple of […]
Filesystem Hierarchy Standard
For those of you managing GNU/Linux systems, you are certainly familiar with the wide range of filesystem heierarchies and utility locations. This makes it difficult to move between different vendors’ distributions. This is changing, in a large part due to the FHS standard. Check it out: http://www.pathname.com/fhs/
Adding Swap Space on the Fly in Linux
Sometimes in the course of a system’s existence you find that the swap partition you set up at install-time just isn’t enough anymore. Maybe you’re upgrading your system to RedHat 7.1 from a version of RedHat that used less swap in relation to physical RAM. Perhaps you’re running Oracle. Or maybe you’re adding more memory […]
Linux Kernel 2.4.9 Released + some tips
You can get it from the mirrors here: kernel.org/mirrors or here: kernel.org. Check our our article on compiling the Linux kernel. One trick we’d like to remind you of from the article is to use “make oldconfig” to migrate your old .config file (usually in /usr/src/linux). You will be asked about just the options that […]
Aliases & Functions in Bash
You might save some time and have a little fun by putting some aliases and functions in your .bashrc file. You can put functions or aliases in .bash_profile or .bashrc in your home directory. But by using .bashrc instead of .bash_profile, they’ll be read in not only when you log in, but whenever you start […]
Creating a Serial Console Bootdisk for Red Hat 8.0
In this article, we showed how to build a serial port multiplexer that allows up to 16 different servers to be controlled from one serial port. We needed to upgrade our servers to 8.0, and, of course, we wanted to use the serial port to do it rather than lug a monitor and keyboard over. […]
How Many Open Files?
We knew the answer to this question once, back when the world was young and full of truth. Without hesitation, we’d have spouted “Just take the output of lsof | wc -l!” And it’s true enough, in a general sort of way. But if you asked me the same question now, my answer would be: […]
Modifying a Red Hat 8.0 Install Diskette
In this article I struggled with a Barracuda ST15150N drive that had problems with Tagged Command Queueing. Well, it is nice to have an install diskette that works with a serial console and works with the ST15150N. This article will guide you through the modification of a stock RedHat install boot disk. I will start […]
The Red Hat Dilemma and One Solution
Red Hat’s maintenance policy is nasty. On the one hand, they need to make money, and maintaining distributions is expensive. On the other hand, for those of us who use Red Hat in budget environments, we can’t really afford their advanced server product, and can’t afford to change to a new version every year. One […]
Stupid Bash Tricks: Magic Carets Correct Munged Commands
We all have fat fingers sometimes and mistype commands, often transposing letters in a word or leaving letters out. When using Bash, you can fix it with the magic carets instead of retyping the whole command. example: [root@pippi opt]# usradd -u 666 -g 100 udergahad bash: usradd: command not found Oops, it should be “useradd”. […]
Analysis of SCO’s Las Vegas Slide Show
Check out Bruce Perens’ analysis here, and ESR’s An Open Letter to Darl McBride.
Using Samba to Authenticate GNU/Linux Against Active Directory
Samba 3.0 allows Linux to authenticate against Active Directory and access shared resources on a Windows 2000 server. Samba 3.0 is still beta. For info on the status, see the status page at samba.org. This article will detail the procedure to get this running with Red Hat 8.0. First, get the Samba distribution from samba.org. […]
Upgrading Gentoo
It has been awhile since we powered up the Sparc64 box we loaded Gentoo on in this article. Well, links was not on the box, and we wanted it. Emerge failed: srv-44 scsi # emerge links . . . !!! Couldn’t download links-2.1_pre2-patch.tar.bz2. Aborting. Doh! We have to emerge portage and sync it: srv-44 scsi […]
Meet the Amazing Mr. lsof
Buoys and gulls, I’d like to introduce the lsof command. Say that you were moving a whole bunch of files, and there was no indication of what file was currently being moved? lsof shows (lists) open files. For instance, if you were moving a bunch of files from directory sales, you could see exactly what […]
Problems Using Loadlin With Large Kernels
We ran across an interesting problem when using our trusty loadlin boot diskette to boot one of our machines when we had a grub freakout: Uncompressing Linux… ran out of input data — System halted_ It turns out that this happens when the kernel is over 1 meg. There are a couple of options. There […]