Lets you have up to 42 servers (84 processors!) in a single rack
High-speed Ultra3 SCSI
Dual PCI slots
Nearly twice as expensive as the DL320
When it comes to servers, you can choose one of two paths. You can go for raw power, with four-way or eight-way processors, gigabytes of RAM, dozens of hot-swap hard drives, and hot-swap PCI buses. Or you can go for density, stuffing as many servers into as small a space as possible.
The ultimate expression of rack density is the 1U server, which stands at 1.75″ high. You can stuff 42 of these puppies inside a typical server rack. Most major hardware manufacturers offer 1U servers, including Compaq, Data General, Dell, and IBM, but what prompted us to review these two entries from Compaq, the ProLiant DL320 and DL360, is that the company offers two different models — they are outwardly quite similar but have distinct design philosophies.
During the review process, both models performed spectacularly under Red Hat 7.0, our test distribution. It’s not a question of whether these are good servers for a high-density data center; the issue is which server fits the application best. If you’re running a Web server or file server, you should go with the less expensive DL320.
If you are running an application server or perhaps a transactional database, then you should choose the higher-performance, higher-availability (and higher-priced) ProLiant DL360.
Compare and Contrast
The biggest differences between the servers can be found in two areas: processor and disk subsystem. The DL320 has a single Pentium III processor and offers either ATA (also known as IDE) or Ultra2 SCSI-based disks; the tested model had a single 800 MHz Pentium III processor, 1 GB RAM, and two 10 GB ATA/100 drives. The DL360, which looks outwardly quite similar, comes with one or two processors and Ultra3 SCSI-based disks; the evaluated system had dual 800 MHz Pentium III processors, 1 GB RAM, and two hot-swappable 18 GB, 10,000 RPM Ultra3 hard disks. (Both servers also come in faster versions — up to 933 MHz for the DL320 and 1 GHZ for the DL360.)
When you get beyond those important differences, the machines start to look the same. Both have dual 10/100 network interface cards, for example, which were immediately identified and properly configured by Red Hat 7. Both have lots of video RAM so that you can have a decent sized X Window console if you like administering a server via KDE or GNOME. Both are limited to a single power supply. Both have a wide range of OS support; Compaq officially supports not only Red Hat, but also SuSE 6.3 and 7.0, Turbolinux Server 6, and Caldera eServer 2.3. The company offers a preload of Red Hat 7, but we manually installed the OS onto both servers.
What are these servers going to set you back? As equipped for this review, the DL320 has a list price of $4,434. The DL360 costs $8,081 — nearly twice the price.
It’s All In the Details
In many ways, the ProLiant DL320 is like a Compaq consumer PC squashed into a pizza box. With the single processor and dual-channel 100 Mbps ATA disk bus, that’s mainly what it is. Don’t underestimate a single processor machine, particularly for lightweight tasks like file serving or simple Web serving (which isn’t too different from file serving) or driving a sendmail system. On the other hand, some tasks — running an application server or Web site with Java servlets, a transaction database, acting as a Beowulf cluster, racking up a high score at SETI@home — should really have the dual-processor power of the DL360.
What about the disk I/O subsystem? For the past ten years, it’s been “assumed” that a server uses SCSI hard drives and that desktops use ATA drives. That made a lot of sense. Back when drives were flakey, the ATA bus (which means “AT Attachment”; it used to be called IDE, for “Integrated Drive Electronics”) poked along at a snail’s pace. But the latest revision of the ATA spec, ATA/100, zips along at 100 Mbps — faster than Ultra2 SCSI’s 80 Mbps. Given that only two hard drives can sit on an ATA bus (compared to 7 or 15 on a SCSI bus), a 100 Mbps bus is more than adequate.
Our only beef with the DL320′s ATA system is that the hard disks themselves are slow. The DL320 we tested used the 10 GB Seagate Barracuda ST310216A drive, with a rotation speed of 7,200 RPM and 8.2 milisecond access time. By comparison, the 18 GB Ultra3 SCSI (160 Mbps) drives in the DL360 spin at 10,000 RPM and has a 5.2 milisecond access time. For driving a database, you’re better off with the faster drives and the SCSI subsystem. But if the server is stuck in the Web server role, processing middleware, you should be happy with ATA.
Another difference in the servers’ disk subsystems is that the DL360 includes a hardware-based RAID controller, which can either span the two disks into a single logical volume or set up the drives with hardware-based mirroring. If that’s important, then the DL360 is the only game in town.
A final difference worth pointing out is in server expendability. The DL320 has only a single PCI 64-bit 33 MHz expansion slot — we couldn’t see why; there’s plenty of room inside the chassis to stuff a second slot. But if you like gigabit Ethernet, want to put a SCSI card inside to drive an external tape array, or want to put the server on a Fibre Channel-based storage area network, you’ll be only able to pick one. By comparison, the DL360 has two 33 MHz slots (one 32-bit and one 64-bit) and also includes an external SCSI port for a tape drive.
Both servers get the job done, though the DL360 is clearly a better machine, offering additional performance and scalability, albeit at a higher price. If your goal is to pack a lot of processors and OSes into a tight space, either server can do the job. With the DL320 for lighter-weight tasks, and the extra oomph provided by the dual-processor DL360, you’ll have a good combination for most data-center tasks.
Fatal error: Call to undefined function aa_author_bios() in /opt/apache/dms/b2b/linux-mag.com/site/www/htdocs/wp-content/themes/linuxmag/single.php on line 62