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 […]

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 […]

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 […]

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 […]

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 […]

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

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 […]

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 […]

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 […]

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/

One problem with Red Hat systems is that the kernel config is not as simple as, say, Slackware. You can’t simply just select the modules you think you need, add in devices, etc. and have the system boot correctly. The Red Hat config is quite customized. This is particularly true for workstation configs that use […]

Linux From Scratch is a GNU/Linux distribution that you compile and piece together yourself. Gerard Beekmans and the LFS team have published LFS 4.1 as a book with a companion CD. We think that this is a fabulous way to document the heart of GNU/Linux. Own your own distribution. Don’t be buffeted about by corporate […]

Did you know that you can recall the last argument to the last command you typed by using the special variable !$. This can be handy when you are working with host names, long file names, all sorts of things. A few examples: See if a host is up and log in: usr-3@srv-3 usr-3]$ ping […]

For a serious analysis of what is going on with the whole SCO/IBM thing, check out the OSI Position Paper. But, for some Friday fun, check out The GNUkes of Hazzard.

We ran into a couple of interesting problems with modules. The first one dealt with SCSI emulation with IDE drives. You need SCSI emulation if you want to write to your IDE CD-ROM with Linux tools. In the past, we have recompiled the kernel with SCSI emulation, but it is so much easier if you […]

Building from source is fun, but it’s easier to distribute RPMs to a bunch of machines. You may recall that we recently built and installed the OpenTDS libraries and SQSH, a dandy little command line tool for use with MS SQLServer. These built nicely on my RedHat 7.3 system, and I have a bunch of […]

[or… how I learned to stop worrying and love the /etc/group file] On Red Hat, the default permissions for a serial port are: ls -l /dev/ttyS1 crw-rw—- 1 root uucp This means that root is the owner and group is uucp. No others have access to the serial port. In order for a non-root user […]

Urbana used to work with a guy who routinely shut down GNU/Linux by typing: sync sync halt That just sounded plain crazy. Why not use shutdown? Well, we just figured he was just a little old-school. The command appeared to work (manpage for sync, manpage for halt). Now, our robocoop is running a giagd system, […]

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. […]

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: […]