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 […]

We run Gentoo, and in our make.conf file we had CFLAGS=”-march=pentium4 -O3 -pipe -fomit-frame-pointer”. Well, it turns out there is a bug. If you run this script: python -c ‘int(10.1); int(10000.3); int(1.2)’ You will get an overflow error. The fix is to use CFLAGS=”-march=pentium3 -mcpu=pentium4 -O3 -pipe -fomit-frame-pointer”. We just ran emerge glibc, and the […]

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: […]

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 […]

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 […]

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”. […]

Check out Bruce Perens’ analysis here, and ESR’s An Open Letter to Darl McBride.

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. […]

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 […]