January 01, 2002
Infrastructure Product Review | Being the Perfect Host (Web Techniques, Oct 2000Brian Wilson
If you're thinking about hosting a Web site on your own colocated server, you're probably considering a rack-mount Linux box for the price and stability. But what do you get when you buy a dedicated Linux server? How much work will you face to get the box into a rack and onto the Internet?
I checked out two typical systems, a FullOn 2x2 from VA Linux and 1U Server from Penguin Computing Systems. Since I started working on this article the FullOn's name has changed: Now it's called FullOn 2230.
These two servers are in different categories so it wouldn't be meaningful to do a performance comparison. For details, visit the vendors' Web sites; VA and Penguin now offer both 1U and 2U servers that are very similar in features and price.
The Hardware
Both VA and Penguin are system integrators. They assemble systems using standard parts; you're paying for the value they add by testing and selecting what they feel are the best parts available and by preinstalling the operating system. I think they made very good choices. Both use Intel motherboards and Quantum hard drives. The FullOn uses an ATX server motherboard—the Intel L440GX+. The 1U Server uses a MicroATX board designed for compact desktop systemsthe Intel CA810E. Both are high-integration boards; disk, 10/100 Ethernet, and video controllers are all on the motherboard so no other plug-in boards are required. This means the boards can fit more into the slim cases. Both systems include CD-ROM and floppy drives.
The VA Linux system is a 2U server (which means it's 3.5 inches tall). It has slots for four hard drives, and two Slot 1 CPU sockets. It has both SCSI and EIDE disk controllers on the motherboard. The test unit came with a 700 MHz Pentium III and a speedy Quantum Atlas 10K Ultra-2 SCSI drive. Two PCI cards can be installed using included riser boards. Two noisy 80MM fans behind its front panel draw air directly through the hard drive area. There are also the usual fans on the CPU and in the power supply. Over 24 inches deep, the FullOn protrudes several inches further out the back than most of the rack-mount servers I've worked with. Because ISPs charge by the vertical inch in racks, this extra depth won't be billable, but it's inconvenient in tight spaces.
The FullOn has a removable plastic trim panel on the front. It restricts air flow, which is bad, and it blocks access to the drives and power/reset buttons. There's a key lock to secure it.
The Penguin system is a 1U server. Because it's just 1.75 inches tall, there's space for only one hard drive, and the motherboard uses a low-profile PGA-370 socket for the CPU. The test system has a 550 MHz PIII (700 MHz is available) and Quantum Fireball Plus KX Ultra-66 ATA drive. You can squeeze in one PCI card on a riser board. Three little 40mm fans in the front panel draw air directly onto the hard drive. They aren't as noisy as those in the FullOn. As with VA's system, the power supply fan exhausts out the back. The 1U is just over 18 inches deep. It has rack-mount brackets only on the front; note that some ISPs will have racks that require center or four-post mounts.
One major reason to chose PC server hardware is that you can use just about any PC parts to get a defunct server back up and running in a pinch. The most common failures will be hard drives and power supplies. When you're pressed, you can cannibalize a desktop system for many parts (up to and including motherboards) to aid an ailing server.
Both systems use nonstandard power supplies. A thin 1U case requires this, but VA also chose to use a long, narrow supply, though other 2U servers I've seen (including Penguin's 2U) use standard ATX power supplies. So if you go with either of these systems, plan on buying a spare power supply to keep on hand.
Component accessibility is poor in many rack-mount systems, and these two aren't exceptions. After you pull the 1U server out of the rack, you must remove 10 screws to get the lid off. You can then get immediate access to everything inside. But once you remove the lid, don't move the chassis around any more than necessary. Without the lid bolted on, moving the chassis will flex the motherboard and potentially reduce its reliability. It's hard to make such a thin box stiff, and though this one is pretty good, flexing is still a concern.
The FullOn has a 3/4 length lid fastened on with just two thumbscrews, so access to the motherboard and power supply is fast and easy. Alas, the front quarter of the chassis is a welded box. This makes the chassis stiffer than many, but it also makes it hard to get at the drives. To replace them, you must first pull out the CD-ROM/floppy unit and then remove the front fan/grill unit. The newer FullOn 2240 model has hot-swappable hard drives that are easy to access, but they use 80-pin SCA SCSI drives that are more expensive and much less common than the 68-pin Ultra-2 drives. So again, plan on keeping a spare on hand.
The Documentation
Both vendors include brief quick-start booklets to help you through the first power-on and configuration steps. The VA system includes a copy of Running Linux from O'Reilly, and a special manual for its hardware. It provides good detail and covers how to deal with the numerous possible motherboard and drive configurations.
The Penguin system comes with the standard Intel motherboard manual and CD-ROM, but its relatively simple chassis doesn't really call for a special manual. Penguin includes two books, which are basically printed copies of the Open Source LDP manuals and the Linux "HOWTO" and "mini-HOWTO" documents. The typesetting isn't as pretty as O'Reilly's, but you get about five times as many pages. The same documents for both systems are also available online, but having paper copies can be handy, especially for beginners.
The Software
Both systems come with the server version of Red Hat 6 Linux preinstalled.
Penguin includes the standard Red Hat boxed set with its distributions, which means you get the CDs and the official Red Hat manual set. When you decide you want to move beyond basics, you can use the discs and manual to install Red Hat on a spare machine.
VA Linux includes a recovery disk, which is actually its own enhanced version of the Red Hat distribution. The company adds support for the more advanced configurations of its servers, such as more RAID and multiprocessor support. It has also been working to fix the nasty NFS bugs in Linux, so the version of Linux it distributes includes those patches. VA deserves a big hand for this because its changes will be rolled back into the public domain Linux kernel.
As with the standard Red Hat CD, the CD that VA includes can be used as an installation disk and as a recovery disk. If you're a beginner, though, you'll want supplemental documentation to use it: either a copy of the standard Red Hat distribution itself or one of the many books now available on Red Hat.
Once It's out of the Box
If you're new to Linux and you're expecting something like a Cobalt RAQ with its Web-based management system, you'll be disappointed. Over the past two years, the popular Linux distributions have made great strides toward being easier to set up, and Red Hat is pretty good. If you have the basic network information (an IP address, gateway address, DNS servers, and domain name), it's pretty easy to get either of these systems running.
VA has an edge here. The first time you power up, the system walks you through the process of setting the root password, network settings, time zone, authentication method, and which services will start at boot. The steps in this process are covered in the quick-start guide.
Penguin provides the information on how to change those settings in its quick-start guide, but it's not written as a step-by-step procedure, so you'll have to infer which steps are required. The manual mentions that you can run netconfig and linuxconf instead of manually editing system files. You can use these tools on the VA system for maintenance, too.
Here's a tip: If you want to get the same effect on the Penguin or any other recent Red Hat installation, as root, type
Here's one thing neither quick-start guide mentions that's important if you want to log in remotely via telnet: You'll need to create a user account to get remote access. You can't connect via telnet and log in as root; the system will refuse to let you in. Use the
The Penguin system was shipped to me with telnet and ftp disabled as a security measure. This is a good idea, but almost everyone will need one or both services. Systems almost always come with too many services enabled by default and this makes a server more vulnerable to attack. Don't turn on any services you don't need.
Page 10 of the Penguin manual describes how to enable them. You have to edit the file /etc/inetd.conf to uncomment the lines for ftp and telnet. Then you have to issue the command
If you enable these services, you really should also restrict their use by setting up the /etc/hosts.allow file. Section 8.2 of "The Linux Security HowTo" document will explain how to set this up.
If you'll be connecting to your server over the Internet, I strongly recommend that you install OpenSSH to get a more secure connection protocol than the ones offered by telnet and ftp. Unfortunately it's not yet part of any Linux distribution and the installation process is too involved to describe here.
Conclusions
A system like the 1U Server would be a very nice system for smaller sites. The FullOn with its faster CPU and SCSI drive will handle more hits, but it takes twice as much vertical rack space, and that could mean a bigger monthly bill from your ISP. For example, there's an ISP in Santa Rosa, CA (Sonic.net) that will let you colocate a 1U server for free (you still pay for bandwidth). The next step up is 4U at $150 a month. So the savings would pay for a 1U server in a year.
I worked with the support departments at both VA and Penguin to resolve minor issues. They're both good. VA Linux has a formal policy of one-year or six-incident software support and one-year hardware support. Penguin doesn't have a stated policy but lists tech-support phone numbers.
Both VA and Penguin have good information in the support areas on their Web sites, and it's accessible to anyone. VA bought the linux.com domain name last year and has committed to making a major effort with the O'Reilly Network at building a support center for the Linux community.
I don't think you could go wrong ordering servers from either of these companies. As configured, the Penguin 1U Server is about $1830. The VA Linux FullOn 2230 is a bit over $2500. For a basic Web server, unless you're planning on getting lots of traffic or have unusually high storage requirements, I would say the smaller 1U system is a better way to go. It's still very fast, it's less expensive, and it takes up less rack space.
As I implied when I mentioned SSH above, security is always a big issue when connecting a server to the Internet, regardless of who makes it or which operating system is installed. It's now relatively easy to get systems like these set up, but even the very latest Red Hat systems have weak spots that you can work on. Read up on it! What you don't know can hurt you.
Brian is a Linux system integrator and consultant with Harbro Systems in Santa Rosa, CA. You can write to him at bwilson@harbrosystems.com.
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