HP NetServer 5/166 LS4

More Reliability for Your Money

The last thing you need is adead server. When your server goes down, your business generally goes with it.That's why you need a machine that can minimize downtime, whether it's from asoftware glitch, a hardware failure, or user error.

Some servers are low in cost, but they may be mediocre in performance. Youhave to weigh the advantages of a larger-scale, more robust platform against thecost of the system and of downtime. You don't gain anything by buying a $5000bargain-brand server if you end up losing $10,000 an hour each time it crashesor burns out a component.

That's when you need to consider a system such as one from theHewlett-Packard (HP) NetServer family to handle your mission-criticalapplications. If you need high performance, you want the LS series. TheNetServer LS machines are designed to start up and stay up. If something goeswrong, these machines make diagnosing and fixing the problem simple and quick.Features such as hot-swappable disks (using either software or hardware RAID),remote diagnostics and manipulation, and other automatic software- andhardware-management capabilities all ensure that your system is reliable andalways available. We tested the NetServer 5/166 LS4.

Test System
Quad-processor 166-MHz Pentium>128MB of RAM>1MB of L2 cache per CPU>8GB (4x2.0GB) Fast and Wide SCSI-2 disks>Software RAID-5>4X CD-ROM>Remote Assistant Card

Processors
You can get an LS series machine in a variety of configurations, and you cantailor its Pentium processors--not just memory and disk--to your needs. You havea choice of clock speeds (100 MHz, 133 MHz, or 166 MHz) and from one to fourCPUs. (You can simultaneously run a uniprocessor and a dual-processor board inone machine.) These options are easy to upgrade in the field simply by replacingthe processor boards when you need faster ones or by adding a board to boost thenumber of processors from two to four.

Each CPU has its own 1MB Level 2 cache unit--but only 512KB on the 100-MHzand up uniprocessor boards--which significantly improves system performance overmachines with shared cache for dual-processor boards. In a Windows NTMagazine Lab test script, we used Adobe Photoshop 3.0.5, which sportssymmetrical multiprocessing (SMP) capabilities. We recorded a 30% to 50% speedboost for each additional CPU. On a shared-cache system, we saw only a 10% to15% boost.

HP's proprietary Extended Express Bus, a high-speed, scaleable bus for SMP,further enhances the CPU performance of the NetServer LS. HP and Intel jointlydeveloped this 64-bit main system bus, which runs at 66 MHz. It has atheoretical data-transfer limit of 6400MB per second (MBps), thus providing agreat deal of growth potential for more and faster peripherals and for fasterCPUs. With current PCI technology (32-bit, 33 MHz, running at 132MBps), however,the system uses only 264MBps of that bandwidth (the average data-transfer ratewith a dual PCI bus architecture).

The CPU-to-cache bus runs with an effective bandwidth of 528MBps, so thesystem's architecture won't be an impediment to future upgrades. Itsdata-throughput capabilities make it ideally suited for information-intensivetasks, such as transaction and database processing, or as a multi-usercompute/file-and-print server. Windows NT operates well on this machine, whichfully uses NT's 32-bit power, SMP, and software RAID capabilities.

Memory and I/O
The test system came with 128MB of RAM, which is about right for aquad-processor machine. Using two daughter cards, the NetServer 5/166 LS4 cansupport up to 768MB of error-correcting code (ECC) parity memory; one card (64MBstandard) comes with the stock configuration. The ECC memory has a high level ofredundancy, so most hardware failures will be transparent to end users. Whilethe system stays up and running during such a problem, the system administratoris notified of the fault. You can use the supplied diagnostic utilities todetermine the location of the bad memory module and replace it during theserver's scheduled downtime.

The I/O capabilities of the NetServer LS are extensive, to say the least.The I/O bus is what HP calls a Dual Peer PCI Bus, a peer-to-peer architecturewhere both PCI buses talk to the system bus, providing a full range of PCIcapabilities. Each PCI bus is 32 bits wide with a bandwidth of 132 Mbits persecond (Mbps). This design allows for more PCI slots without the slowdown of abridge architecture. You can separate devices of differing speeds to optimizethe performance of your system. For example, you can separate your slow networkcards from your fast SCSI controllers. Five PCI slots are on the single- anddual-processor systems, but only four slots are available in the quad-processorversion--the extra processor card blocks one slot.

Dual PCI Fast and Wide SCSI-2 controllers are embedded on themotherboard--equivalent to two Adaptec 2940W controller cards--giving you amultitude of storage options. The NetServer LS has out-of-the-box RAID mirroringand duplexing without any extra hardware because of the two embeddedcontrollers. For example, you can configure your system for fault tolerance inthe operating-system partition and other system resources on the internal disks.Then you can use a separate controller and an external disk subsystem for data.

The main CPU chassis can hold up to 25GB. Its pedestal form-factor can holdup to six half-height 3.50" hot-swap drives: Each bus can control threedrives, with RAID 0, RAID 1, software RAID 5 (operating system-dependent),striping, striping with parity, or mirroring to enhance performance.

You have several other options in configuring your disk subsystems. You canuse a single hard drive that holds the operating system, on one embeddedcontroller (install the drive in the common 5.25" bay) and run the RAIDdrives for data only, on the remaining controller. Or, you can put the sixhot-swap drives on one bus and use the second bus for an external storagesubsystem holding up to an additional 25GB. The system supports fullyhot-swappable disks if you use HP drives, and you have an option for RAID 6 viaa PCI RAID disk-array controller. The performance depends on your data mix, soyou have to base your decision between software and hardware RAID on your users'needs. However, in the case of a hardware failure, hardware-based RAID is fasterthan software-based RAID on the rebuild, and the performance hit during thefailure is slightly lower.

Other standard hardware includes a 4X CD-ROM drive, a floppy disk drive,and a bay for a half-height 5.25" device, such as a backup tape drive.There are two PCI, four EISA, and two shared bus-master expansion slots, and astandard set of external ports: one enhanced parallel, two 9-pin serial, video,and PS/2-style keyboard and mouse. The NetServer's video is an accelerated EISASVGA controller from Cirrus Logic, with 512KB of DRAM, upgradeable to 1MB.

Performance
The Windows NT Magazine Lab's tests proved the NetServer LSto be a champion system. Its hot-swap drives are indeed hot-swappable; otherthan displaying a message on the console detailing the missing unit, the systemdoesn't even hiccup when you remove disks.

To test the NetServer's SMP performance, we ran a custom Adobe Photoshopscript on one, two, three, and all four processors. Each additional CPU improvedprocessing about 40%. The extra megabyte of Level 2 cache per processor makesall the difference, as you see in graph 1, which compares a Diamond Flower (DFI)Doubleshot with a shared 256KB Level 2 cache to the NetServer 5/166 LS4'sseparate 1MB Level 2 caches. The NetServer's SMP architecture should mean thatas an application server, it can support many concurrent users without slowing,and SMP-enabled applications such as Photoshop will perform excellently.

Management and Availability Features
HP designed the NetServer's numerous system-management features to reducethe cost of ownership and maintenance. On the hardware side, the NetServer haseverything from a specialized data bus for querying hardware to a single-boardcomputer that you can add for remote control. On the software side, HP ships theNavigator CD, which contains several assistants to simplify systemadministration. A floppy disk taped to the inside of the computer's cabinetprovides utilities to diagnose failures and suggest fixes in the event of atotal system crash.

Beyond the ECC memory and hot-swappable RAID drives, HP built inhardware-reliability and -testing capabilities with its proprietary I-squaredC-Bus. This simple, low-speed, three-wire serial bus connects the CPU to disksand other peripherals, so you can manage the system. With sensors for conditionssuch as operating temperature and voltage, the system logs failures tonon-volatile RAM (NVRAM) for later access. The software on the Navigator CD orthe utilities on the special boot floppy can read the log. Moreover, using thisbus, the operating system can interrogate the system and report failures to theadministrator.

An interesting option on the NetServer is the Remote Assistant, a hardwareadd-in card. It's a computer on an EISA card (with its own backup power supply,modem, etc.). It sits passively on the bus (attached to the I-squared and EISAbuses and main power) watching temperature, voltage, and other systemparameters. HP says this card is for "out-of-band management" becausethe system can suffer a complete failure, and without being anywhere near theconsole, an administrator can still use a terminal emulator to dial in to theboard from anywhere and work on the system.

When the Remote Assistant Card detects a failure, it either sends out anetwork message or pages you about the fault. If you're away from the office,you can dial in to the system--whether you are running NT remotely or not--tomanage it. You can get reports on its status, bus usage, and other statistics.

Although the Remote Assistant Card can't redirect the NT user interface,you can boot the system to DOS. Then, anything you can do from the keyboard,monitor, or power switch at the console, you can do remotely.

You see everything that's on the server screen. If a crash occurs, thesystem automatically captures the console screen into NVRAM, so that you canview the image. From any error messages, you can determine why the systemhalted. Screen 1 shows the Remote Assistant, which lets you power up remotelyafter an uninterruptible power supply fault, or cycle the system's power--again,these are tasks that otherwise require you to sit in front of the console to do.

The terminal application that HP sends with the Remote Assistant Card isANSI-compatible, so a program such as ProComm will work, but it will lackcertain features. The Remote Assistant software has macros tailored specificallyto features on the card, and it supports control codes such as Ctrl-Alt-Del andAlt-F8 for performing system functions: You can enter the EISA configurationutility to set up cards and peripherals, use the CMOS setup routines, and rebootthe system. Macros can, among other things, send character strings to remotelyboot and log on to the server or to monitor bus statistics and usage, as screen2 illustrates. However, the Remote Assistant card is not an independent modemand will not function as an ordinary dial-in port. You need a separate modem todo ordinary server maintenance through NT.

NetServer also has software to match its hardware-reliability features. TheNavigator CD provides assistants for configuration, information retrieval,diagnostics, and server management. In the event of a system failure, you canuse the NetServer Assistant for "in-band management"--where you are onthe network and can resolve problems locally. This Assistant notifies HPOpenView across your network, which in turn, notifies the administrator. TheNetServer Assistant can also work with resource management to notify you, forexample, when disk space is running low.

Other software utilities on the CD include Automatic Server Restart: Thesoftware can detect whether the system is hung--a software hang, rather than ahardware fault--and reboot itself. An optional guided tour is available for theinstallation and setup process, and so is an Information Assistant with all thesystem documentation online. The floppy disk contains another copy of theDiagnostic Assistant to help solve setup problems by looking at system hardwareand suggesting sources (loose connectors, etc.) and fixes. You can even set up autility partition that logs these problems for later queries. With thisout-of-the-box support for the operating system, system management, andreliability assurance, NetServer is an excellent system for mission-criticalapplications.

Well Worth the Money
Microsoft authorizes HP to support Windows NT, so you won't get therunaround from the technical-support people telling you to take your problems tosomeone else. Special support plans are also available.

Our experience with the NetServer 5/166 LS4 was very good. Although it isexpensive compared to smaller systems, its performance and reliability featuresmake it well worth the money. HP's technical support was excellent, andrepresentatives quickly and efficiently handled any problems we encountered.(For example, we experienced random crashes with one of our benchmark tests; thecrashes ended up being the fault of Service Pack 2.) If you're looking for amachine you can rely on, the NetServer 5/166 LS4 is a good choice.