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/

It is a good idea to test this and upgrade to it if you are running a 2.4 kernel. There have been some problems with virtual memory with some of the 2.4 releases. There was also a nasty bug with symlinks w/ 2.4.11. Get it from: Kernel.org Mirrors. Seems to work fine for us. We […]

There are two main bootloaders you can use with Linux these days: LILO and GRUB. Red Hat uses GRUB by default now. Most distributions used LILO until quite recently. We built a fairly souped up Linux workstation w/ a large Maxtor IDE drive. We decided to use Sorcerer GNU/Linux; however, we had a horrid time […]

It has been awhile since we have purchased workstation hardware for a new system. We settled on the Asus P4B w/ a Geforce2 MX400 AGP video card. As of February 2002, it seemed like the best CPU value was a P4 1.7GHz. We are running Sorcery GNU/Linux so we can squeeze out all of the […]

Red Hat includes the checkconfig & service utilities to help you manage your start up scripts and save you a lot of typing. This is handy when you’re adding your own services and also in managing the already existing services. chkconfig is available if you want to use it on other distributions that may not […]

In our article Serial Port Multiplexer, we documented a design for a shoestring budget console sharing device. Basically, if you have a bunch of servers that can run their consoles via a serial port, you can use our device to monitor all of these consoles remotely. Well, one of our boxes is sick, and we […]

If you are running Red Hat, you need to keep your RPMs up to date. Red Hat has a service you can subscribe to, but if you wish to do this manually, browse to the house of mirrors, and pick a site that has updates for your architecture. We put all of the updates in […]

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 […]

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 […]

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 […]

[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 […]

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. […]

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 […]

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”. […]

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. […]

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 […]