Linux

What large market for x86 Unix?

Dave Farquhar Linux , , , , , , , , , ,
What large market for x86 Unix?

In a bizarre turn of events, SCO has sued IBM for not less than $1 billion, claiming IBM willfully destroyed SCO’s business by handing its intellectual property over to the Linux movement.

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Optimizing a web server

Dave Farquhar Linux , , , , ,

Promises of better Apache performance have me lusting after lingerd, a very obscure utility that increases performance for dynamic content. It’s been used on a handful of little sites you might have heard of: Slashdot, Newsforge, and LiveJournal.
Unfortunately there’s no Debian package, which means compiling it myself, which means compiling Apache myself, which also means compiling PHP and MySQL, which means a big ol’ pain, but potentially better performance since I could go crazy on the GCC optimization flags. Hello, -O3 -march=i686!

And if I’m going to compile all that myself, I figure I might as well compile it all myself and get the high performance across the board and get GCC 3.2x into the picture for even better performance. The easy way to do that is with lfs-install, which builds a system based on Linux From Scratch. For workstations I’d rather use something along the lines of Gentoo, but for servers, LFS is small, mature, and reasonably conservative.

Supposedly metalog offers improved performance over the more traditional syslogd or sysklogd. The good news is that those who are more sane than me and sticking with Debian for everything can take advantage of a Debian package (at least in unstable), and just apt-get away.

If I have any sanity left, I’ll think about minit to replace SystemVInit and save me about 400K of memory in a process that’s always running, and fgetty to save me a little more. I’ve tried fgetty in the past without success; it turns out fgetty requires DJB’s checkpassword in order to work.

Keep in mind I haven’t tried any of this yet. But the plan sounds so good in my current sleep-deprived state I couldn’t help but share it.

Sam’s Club offers $299 Red Hat Linux boxes

Dave Farquhar Linux , ,

I just read today that Sam’s Club is about to start offering 1.1 GHz Duron PCs running Red Hat Linux for $299.
The machines are beefier than Wal-Mart’s $199 Microtel PCs running Lindows and Lycoris. The machines don’t exactly compete with one another; the 800 MHz Microtel boxes are good enough for word processing and e-mail, and Lindows and Lycoris target users with simple needs. Red Hat targets people with a little more familiarity with PCs, as does AMD. Sam’s is also offering a $399 version with a 2 GHz AMD Athlon XP.

The machines are built by a Kansas outfit called CPUbuilders. The systems utilize a SiS chipset with integrated video. They use PC133 memory and not the newer, faster DDR memory. The 1.1 GHz model comes with 128 megs of RAM and a 20-gig drive; the 2 GHz model has 256 megs and a 60-gig drive. Both have standard amenities like Ethernet, modem, sound, and a CD-ROM drive. The budget model lacks a floppy drive, while the more expensive model has one.

They both appear to be solid, but basic, configurations. It’ll be interesting to see how successful they are in the marketplace.

Finally–GPL antivirus for Linux

Dave Farquhar Linux , , ,

Clamav is a free (GPL) virus scanner for Linux and other Unix systems. It seems to work well. The price is right.
There are very few viruses for Linux, so few that most people don’t waste their time with virus scanning. But if the machine is acting as a server for clients that are vulnerable to viruses–cough–Windows–cough–it’s a good idea to have antivirus software on your server, just so you know your clients are safe.

Debian packages are in Sarge and Sid. Source can be downloaded and built from the link above. Once it becomes better known, it should appear in RPM distributions such as Red Hat in time.

It’s just a scanner, but if it finds an infected file, you can clean it manually with free tools you download elsewhere. Clamav will take care of alerting you, the price is right, and the platform’s right. It’s always been hard to find antivirus software for Linux of any sort, so Clamav is a welcome addition to the family.

We’ll talk a lot more about servers in the coming days.

Dumping a list of installed packages on a Debian system

Dave Farquhar Linux

Yes, Todd, I’m posting an update from work. This’ll save me from wasting time on Google later in life.
Use the command dpkg --get-selections to generate a list of all the installed packages. If you want to replicate a system quickly (say, for disaster recovery or system deployment), redirect the package list to a file (dpkg --get-selections >packagelist). Then, as long as you have a copy of the file, you can install a minimal Debian system and turn it into a replica of the other system with nothing more than an Internet connection and a few commands:



dpkg --get-selections |sed 's/\(de\)*install/purge/' | > dpkg --set-selections

dpkg --set-selections 
dselect install

And they say Windows’ TCO is lower than Linux…

Red Hat and Debian fans debate desktop Linux

Dave Farquhar Linux , , , , , , , ,

Mail from longtime reader Steve Mahaffey on the state of desktop Linux. My responses interspersed within:
SM: It’s been a while since I’ve emailed you, though I still read your site almost daily and comment from time to time.

DF: I appreciate that.

SM: Other than our common faith the most important subject that I could comment on might be desktop Linux.

DF: And it’s been a while since I’ve written about either of those. Too long.

SM: In the past I’ve used Mandrake and Suse briefly, and Red Hat 7.2/3 more extensively. As a server, Red Hat 7.3, booted to runlevel 3, runs until the power goes off at my West Houston home long enough to outlast my UPS. On the other hand, as a desktop OS, Red Hat 7.3 with KDE or Ximian Gnome would crash 1-3 x per week, and Ximian Gnome would get corrupted, requiring me to delete various ./.gnome* config files or files in /tmp to fix it, which most users would not be able to fathom or guess at.

DF: The more advanced desktop environments seem to be pretty sensitive to something or other. I haven’t figured out what exactly. That’s part of the reason why I run IceWM on Debian on my desktop; it’s stable. Running Gnome apps under IceWM on Debian “Unstable” (the experimental, bleeding-edge Debian distro), I’ve been chasing a slow memory leak that eventually consumes all available physical memory and eventually leads to a crash, but it takes a month or two. More on what I think is going on in a minute.

SM: Red Hat 8.0 on my primary workstation, on the other hand, is currently at 43 days uptime. NO CRASHES, once or twice I have restarted the x-server, and once I had a problem with the gnome conifg files. I know that you use Debian mostly, but Red Hat, Lindows, Mandrake, Lycoris, or the like will be the ones to have a mass impact on the desktop. Seems like Lycoris or Lindows was Debian based, though.

DF: I know Lindows is based on Debian. I don’t know Lycoris’ origin. You are correct that Debian will have minimal impact on the desktop, at least in the home. Debian doesn’t give a rip about commercial success and it shows.

I saw Red Hat 8 and Mandrake 9 recently and I was impressed at how far they’ve come. I haven’t touched Red Hat since 6.2 or Mandrake since, well, 7.2 probably. They looked stable and fast. And I saw a minimal (no options picked) Mandrake 9 install the other night. It was 144 megs. I remember not long ago trying to do minimal Red Hat and Mandrake installs and they were 300 megs, at least. That’s definitely a step in the right direction.

SM: Anyway, besides much greater stability, I have enough functionality for most of my needs in programs like Open Office, gnucash, Mozilla or Galeon, Evolution or KMail, etc. Some may have other needs, only met via Windows only programs, of course. I have noticed that RH 8.0 seems on occasion to be slow, but not most of the time. The menus are a little funny … easy to add to the KDE menus, but they don’t always seem to work. With Gnome, it’s easier to add a custom panel to add a non-default application, but it does work then.

DF: Linux currently meets most of the needs I observe on the typical user’s desktop. Not necessarily power users, but for the basic users who are interested in typing simple documents like letters and memos, simple spreadsheets (and let’s face it, an awful lot of spreadsheets use very basic math, if any at all), e-mail, Web browsing, chat, and listening to music, Linux provides solutions that are as good as, if not superior to, those that run on Windows.

I also observe how many users don’t know how to add an application to Windows’ Start menu, or desktop, or that quick-launch thing on the taskbar. It may be easier on Windows, but it’s still not easy enough for most people.

Of course, this is coming from someone who keeps at least one shell window open at all times in Linux and launches apps from there because it’s faster and easier for me to type the first few letters of an app and hit tab and then enter than it is to navigate a menu. For people like me, Linux is much, much superior to Windows and always will be.

SM: RH 8.0 did recognize my nVidia card, but did NOT enable opengl 3d acceleration. I had to install the nVidia drivers from the nVidia web site to get opengl acceleration…apparently Red Hat has decided to not support that at this time. Another oddity is that I have had to turn on the cd sound to play audio CDs by using the kde mixer…can’t seem to do it with the gnome mixer, and don’t know where to hack a config file or file permissions to do this.

DF: Given Red Hat’s history with KDE, it’s ironic that some things work better in KDE than Gnome on Red Hat. Nvidia’s decision to only provide binary drivers (not source) hasn’t proven popular with a lot of Linux distributors, which probably has a lot to do with the OpenGL issues. Red Hat isn’t going to go out of its way to make nVidia look good, and might actually go out of its way to make nVidia not look as good as ATI or Matrox or other companies who are willing to provide straight source, taking the chance that users will blame nVidia rather than Red Hat or Linux. (That’s not a particularly safe bet, but it’s not out of character, given past history.)

SM: Other things… Evolution crashes a lot. I’ve given up and started using KMail (for IMAP since I use my own mail server with IMAP). Galeon is good, but it seems that I had some printing issues and I’ve been using Mozilla more. I’ll have to see how the Phoenix browser comes along…it might be the best choice. Flash and Java required a manual install.

DF: Evolution is stable for me in Debian (more stable than Outlook 2000 under Windows 2000) but I’ve heard that complaint. I have to wonder if Evolution might be picky about the libraries it’s linked to and what it’s compiled with and how? Debian is really conservative; Red Hat is much more apt to use C compilers that haven’t proven themselves just yet. It’s great that GCC 3.2 is so much faster, but if that speed is still coming at the price of stability, let’s back off, eh?

I like Galeon but I don’t print Web pages much. Phoenix is turning into a very nice browser. Lately I’ve been using Mozilla nightly builds for the spam filtering in the mail client and no other reason.

SM: All in all, maybe Red Hat 8.0 is still more a distro that is more suited for corporate environments that have IT personnel around to hand-hold, and which need only modest desktop application abilities. But, it’s coming quite close to the fabled “Aunt Minnie” friendly OS that will really give Microsoft fits.

DF: It’ll take time to get mainstream appeal but I believe it will. Linux PCs in Wal-Mart are a very good thing, because it gives exposure and feedback. The press hasn’t been too kind to the Linux PCs sold there, but if the criticisms are addressed, things will get better, faster, for all distributions. Windows nothing but a really bad Mac wanna-be for 10 years, but it ripened because it infiltrated mass-market PCs. The press applauded Microsoft as it washed its dirty laundry in public. Linux won’t get that same treatment, but I’ll take a criticizing press over a kiss-butt press any day of the week if the goal is product maturity. Windows has been 20 years in the making, but XP still crashes too much.

And as far as Red Hat vs. Debian goes, I may have to give Red Hat another look as a desktop OS soon.

SM: Most of your comments seem to center around Linux and server applications. This is not trivial or unimportant. However, I think that the time for desktop Linux may be getting quite close, and I’d be interested in your comments if you feel so inclined.

DF: My focus has changed in the past year. Two years ago, I did desktop support, and server work in emergencies. About a year ago, I started moving into server support and only did desktop support in emergencies. It’s been a year since I’ve dealt with end users on a regular basis, so I don’t know as much what’s wanted or needed on the desktop anymore and I definitely don’t think about it nearly as much since I’m almost never confronted with it.

I think my thoughts on it are still worth something, since it’s only been a year, but that kind of experience definitely doesn’t age well.

Getting back to the desktop, the apps we need are in place. What they need most now are must-have features that Microsoft won’t supply, or won’t supply quickly. Bayesian spam filtering in Mozilla is a prime example of Open Source beating MS to the punch. A great idea showed up on Slashdot, some early implementations showed up immediately, and within a month or two, it’s in Mozilla’s alpha builds. The public at large will have a usable implementation within a couple of months. And there will be others. I suspect we’ll see lots of examples of it in digital media. I mean, whose design would you rather use, the design of someone concerned only with corporate interests, or the design of a group of users concerned with their fair-use rights and yours and mine?

SM: Anyway, maybe you’ll find my observations to be of interest.

DF: Always.

New Freesco

Dave Farquhar Linux

Freesco 0.3 is out. It now has working PPPoE support, I understand. I don’t know what else it does just yet. But I intend to find out.
Freesco is easily my favorite single-floppy Linux distro, because once you get the hardware going, it’s easy to get running. Anyone familiar with computer networking can do it, without knowing a thing about Unix. And once it’s working, you can move it to the hard drive, which is good, since tiny hard drives are common as dirt and cheap and reliable (Freesco spins the drive down after it’s done booting, so a hard drive should work pretty much indefinitely, seeing as you’ll only reboot the thing when there’s a power failure), whereas floppy disks are anything but reliable.

That’s not to say that getting the hardware going isn’t a pain sometimes, but that’s not Freesco’s fault. Resolving a bunch of IRQ and I/O conflicts to get a 486 with a pile of ISA cards in it working perfectly is a pain no matter what OS you intend to run on it.

Linux network diagnostics

Dave Farquhar Linux , ,

I was doing a little research for Gatermann about Linux networking. I didn’t find what I was looking for, but I found something interesting: a pair of tools co-written by Donald Becker called mii-tool and mii-diag.
The source code for it is available at scyld.com but Debian includes a package for it (mii-diag). It allows you to force your network card to re-negotiate its speed with your hub or switch, which is useful if it’s constantly negotiating the wrong speed. In Windows you can usually open the network control panel and force duplex operation and speed. In Linux, that requires playing around with module options, which aren’t always consistent across drivers (because they’re not all written by the same people) or, if you compiled your driver into the kernel, passing boot parameters. Either way, you’re forced to reboot.

Run mii-diag to find out the status of your card (and commentary on the situation from the authors, in some cases). You can run mii-tool -r to force a renegotiation nicely, or run with the -f parameter to force it to a certain speed (if you’re interested in forcing a speed, you’re probably chasing 100 megabit, full duplex).

If your system is mysteriously not connecting, like my Web server was yesterday after I moved it, this tool can be useful in fixing it. I wish I’d known about it yesterday. I eventually solved the problem by rebooting until it worked right. (I don’t think my server’s 3Com NIC likes my Linksys router/switch much.)

So if you want to change your network’s speed for any reason without rebooting, this is the tool to do it (and it doesn’t make you hunt the Web and Usenet for the module parameters).

Adding a network card to Linux

Dave Farquhar Linux ,

I said yesterday I didn’t remember exactly how to add a network card to Linux machines. I found instructions today. They weren’t entirely correct. So here are instructions (hopefully more correct–I have access to exactly one Linux box right now) for adding a NIC in Linux.
First, determine which module your NIC uses, then install it temporarily with the following:

insmod [module name]

For example:

insmod rtl8139

In RPM-based distributions (Red Hat, Mandrake, Caldera, TurboLinux, UnitedLinux), edit the file /etc/modules.conf or /etc/conf.modules to add an alias for the module. In Debian-based distributions, edit the file /etc/modutils/aliases and then run the command update-modules. In any case, the format of the line to add is the same:

alias eth0 rtl8139

More likely, you’re adding a second NIC, in which case the line would look more like this:

alias eth1 rtl8139

In RPM distros, next you create an interface config file in /etc/sysconfig/network-scripts. The file is called ifcfg-[interface]. Here are a couple of example ifcfg-eth0 files:

# Static IP
DEVICE=eth0
IPADDR=192.168.0.33
NETMASK=255.255.255.0
BROADCAST=255.255.255.255
ONBOOT=yes

# DHCP
DEVICE=eth0
BOOTPROT=dhcp
ONBOOT=yes

In Debian, all network configuration info is kept in /etc/network/interfaces. Here’s a sample configuration:

iface eth0 inet dhcp

iface eth1 inet static
address 192.168.1.1
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255

SuSE is likely to be a bit different. Slackware is virtually guaranteed to be different. I haven’t looked at SuSE in three years and Slackware in five. Hopefully they’re similar enough that this can give you a start.

I’m sure there’s a graphical way to do this in some, if not all distributions, but I prefer to hit the configuration files directly. It’s much easier to explain, and the knowledge is much more portable.

A semi-easy firewall

Dave Farquhar Linux , , , , , , , ,

A single-floppy firewall mini-distribution can be a quick and easy way to save yourself some money if you’ve got an old PC in a closet not doing anything, assuming you stumble across a combination of hardware that works right.
If you don’t stumble across a combination of hardware that works together, you can just as easily spend a weekend and accomplish nothing but uttering strings of four-letter words in combinations never before heard by mankind.

In case you came here looking for hardware that works, here are a few hints. A 10-megabit PCI NE2000 clone in combination with virtually any 10/100 PCI card ought to work fabulously. A pair of 10/100 PCI cards based on the RealTek 8139 chipset, which includes the majority of today’s inexpensive cards, probably will not. If you’re buying new stuff and want ease of use, get a 3Com card and a cheapie. If you want cheap and a little inconvenience, get a Netgear FA311 or 312 and a Realtek 8139-based card, such as a D-Link DFE-530+ or a Linksys. You’ll have to hunt down and install the natsemi.o module to get the Netgear working; most other inexpensive cards on the market will work with the rtl8139.o driver.

Freesco doesn’t supply a driver for the Intel EtherExpress Pro series out of the box. If you’ve got an EEpro, you can make it work by downloading the module and copying it to the floppy, but don’t rush out to buy one. And yes, the 3Com and Intel chipsets are high-performance chipsets, especially compared to the 8139, but remember, routers are machines that pull packets out of a 1.5-megabit pipe (if you’re lucky) and shove packets down an even smaller pipe. In this application, a $40 big-brand card doesn’t give you any advantage over a no-name card that costs $6 at Newegg.com

While these firewalls will technically work fine even on a 386sx/16, trying to make them work with ISA cards can be a long, difficult road. Used Pentium-75s are dirt cheap (and Pentium-60s and 66s are even cheaper, when you can find them) and they’re a lot less trouble because PCI cards don’t require you to rejumper them or hunt down a plug-and-play configuration disk to find out its IRQ and address. I’ve had the best luck with Pentiums that used an Intel Triton chipset or newer (the 430FX, HX, VX, or TX). I’ve tried a couple of boards that had a SiS chipset of 1995 vintage or so, and I could get one network card or the other working, but not both. I don’t want to generalize and say that based on two isolated incidents that all Taiwanese chipsets are junk for this application–for all I know, the problem could have been the BIOS on those boards–but I’ve done this on a handful of Triton-series boards and done well on all of them, and on two SiS boards and failed. Your mileage will probably vary.

How much memory do you need? 16 megs is sheer luxury.

Once you put all this together, the question becomes whether you use a floppy distribution or a full-blown distribution. If you want peace and quiet and cheap, the answer is pretty easy–use a floppy and pull out whatever hard drive was in there.

A full-out distribution like Red Hat or Debian will give you more versatility. You can run meaningful Web and FTP servers if you want (and your ISP allows it). You can run a caching nameserver to speed up your Web browsing. If you feel adventurous, you can even install the Squid caching proxy and speed up your browsing even more (but either use a SCSI drive or put in a bunch of extra memory and run Squid’s cache out of a ramdisk–Squid’s performance on IDE is, to put it mildly, terrible).

I’m having a hard time finding the documentation on how to set up a second network interface quickly. I believe it involves the file /etc/interfaces and the files /etc/sysconfig/ifconfig.eth0 and .eth1, but I don’t have a Linux box handy to investigate at the moment.

Anyway, I like Debian for this application (of course) because I can easily fit a minimal Debian on a 100-meg hard drive.

Once you get your network cards all working and talking to each other, you can build your firewall using this online tool. I just copy it, then Telnet into my Linux box using PuTTY, fire up a text editor, and right-click in the window to paste.

If you want versatility and quiet and don’t mind spending some cash, pick up a CompactFlash-to-IDE adapter and a CompactFlash card of suitable size. Don’t create a swapfile on the CF card–you’ll quickly burn it up that way. Your system will recognize it as a small IDE drive, giving you silent and reliable solid-state storage on the cheap.