Looking for all the performance and functionality of a conventional low-profile server but in half the space? The Dell Computer PowerEdge 1655MC (Modular Computing) blade server could be the ticket. The dual-processor servers — each with RAID-based SCSI storage and on-board Gigabit Ethernet — occupy only 1/2U (half a rack unit) of space, meaning that with few compromises on performance or reliability you can cram as many as 84 full-fledged servers into a standard 42U-high rack. That not only saves rack space but also simplifies cabling, reduces power and cooling requirements, and eases the physical administration of your server farm.
The PowerEdge 1655MC system consists of a 3U-high enclosure that can contain as many as six hot-swappable servers, each of which is equipped with dual 1.4GHz Intel Pentium III processors, dual standard Ultra320 SCSI hard drives with integrated RAID, and as much as 2GB of RAM. Each server also has two integrated Broadcom Gigabit Ethernet NICs (network interface cards), thereby providing the same hardware specs as Dell’s conventional 1U-high PowerEdge 1650 server, with one main exception: Whereas the PowerEdge 1650 has three hot-swappable bays, the PowerEdge 1655MC’s drives are not hot-swappable.
The PowerEdge 1655MC’s enclosure includes two hot-swappable 1048-watt power supplies; four hot-swappable fans; a built-in KVM (keyboard, video, and mouse) switch, which can be used directly or cascaded to a KVM-over-IP solution; and two six-port Gigabit Ethernet switches, each with four Gigabit Ethernet-over-copper uplinks. For managing the enclosure, Dell provides an onboard management processor with its own Fast Ethernet NIC port. The PowerEdge 1644MC’s power is fully redundant; Dell claims that a populated enclosure draws only 850 watts.
That means, in theory, that you could connect a six-server PowerEdge 1655MC rack with as few as five cables: two for power, two for Ethernet (one for the servers, one for enclosure management), and one for KVM-over-IP. If the servers are configured for headless operation, you could even dispense with the KVM connectivity. Of course, in a production deployment, we would advise you to use multiple Gigabit Ethernet uplinks from both switches, both to improve throughput and provide fail-over protection. Note that having the built-in 10/100/1000Base-T switch means that even if the PowerEdge 1655MC enclosure is connected to a slower LAN, the six blades communicate with one another at Gigabit Ethernet speeds — an ideal situation for clustering.
Although the PowerEdge 1655MC blade system lacks serial and parallel ports, each server contains a single USB port that is accessible from the front of each blade. This can be used to connect a USB-based bootable floppy or CD-ROM drive, both of which are included with the enclosure and can be used for OS or app installation.
The review system provided by Dell included four dual-processor blades, each equipped with two 18GB Ultra360 SCSI hard drives and 512MB of RAM. One was equipped with Red Hat Linux, two with Windows 2000 Server, and the fourth was bare. Deployment of the enclosure and blades took less than half an hour, and we needed the manual only to learn the hot-key sequence necessary to operate the internal KVM switch.
We used a bootable CD-ROM to install Windows 2000 on the fourth server, but the blade crashed with a hardware “blue screen of death”. The same problem occurred when trying to install Windows on a different blade. Yet, installing Red Hat Linux 7.3 from a bootable CD-ROM worked just fine. Figure that one out.
Any IT professional adept at deploying servers should adapt instantly to the PowerEdge 1655MC and should be comfortable either deploying them in dedicated racks or mixing and matching them with conventional servers. In a field office or departmental environment, the system could even be deployed on a tabletop; just plop a monitor and keyboard on top of the steel enclosure, and you’ve got a self-contained server farm. You could even dispense with the KVM and use Telnet or Windows Terminal Services across the LAN.
The strength of Dell’s PowerEdge 1655MC system is that its servers perform on par with conventional servers. The high-availability features provided by the onboard RAID, dual power supplies, and dual integrated Gigabit Ethernet switches make the PowerEdge 1655MC an attractive solution — and it’s both smaller and more convenient than a typical rack-mounted server.
On the software front, Dell includes Remote Install, a utility that runs alongside Dell’s Open Manage hardware-administration suite. Remote Install shares the same basic look and feel of Open Manage, is more than adequate for capturing and deploying disk images such as for streamlining OS and application installations, and is easier to use than Hewlett-Packard’s Insight Manager, which HP ships with its own server blades.
We used Remote Install to preconfigure a Windows disk image and push it out to a blade. Dell’s software performed adequately but not on par with RLX’s excellent ControlTower 4 blade management software, which can automatically assign specific blade slots for specific applications and then install, configure, and activate server blades as they’re inserted into specific slots in any chassis of any rack.
When you add it all up, the PowerEdge 1655MC is impressive. More powerful than RLX’s blades, Dell’s servers are chock-full of high-availability features, and unlike HP’sProLiant BL20p , the PowerEdge 1655MC offers Gigabit Ethernet, a fully self-contained system with power in the same enclosure as the blades, and much higher rack density. Based on what we’ve seen, when it comes to high-performance blades, Dell’s PowerEdge 1655MC is poised at the top of the heap.