More Reliability for Your Money

The last thing you need is a dead 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 a software glitch, a hardware failure, or user error.

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

That's when you need to consider a system such as one from the Hewlett-Packard (HP) NetServer family to handle your mission-critical applications. If you need high performance, you want the LS series. The NetServer LS machines are designed to start up and stay up. If something goes wrong, 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- and hardware-management capabilities all ensure that your system is reliable and always 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 can tailor its Pentium processors--not just memory and disk--to your needs. You have a choice of clock speeds (100 MHz, 133 MHz, or 166 MHz) and from one to four CPUs. (You can simultaneously run a uniprocessor and a dual-processor board in one machine.) These options are easy to upgrade in the field simply by replacing the processor boards when you need faster ones or by adding a board to boost the number of processors from two to four.

Each CPU has its own 1MB Level 2 cache unit--but only 512KB on the 100-MHz and up uniprocessor boards--which significantly improves system performance over machines with shared cache for dual-processor boards. In a Windows NT Magazine Lab test script, we used Adobe Photoshop 3.0.5, which sports symmetrical multiprocessing (SMP) capabilities. We recorded a 30% to 50% speed boost for each additional CPU. On a shared-cache system, we saw only a 10% to 15% 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 jointly developed this 64-bit main system bus, which runs at 66 MHz. It has a theoretical data-transfer limit of 6400MB per second (MBps), thus providing a great deal of growth potential for more and faster peripherals and for faster CPUs. With current PCI technology (32-bit, 33 MHz, running at 132MBps), however, the system uses only 264MBps of that bandwidth (the average data-transfer rate with a dual PCI bus architecture).

The CPU-to-cache bus runs with an effective bandwidth of 528MBps, so the system's architecture won't be an impediment to future upgrades. Its data-throughput capabilities make it ideally suited for information-intensive tasks, such as transaction and database processing, or as a multi-user compute/file-and-print server. Windows NT operates well on this machine, which fully 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 a quad-processor machine. Using two daughter cards, the NetServer 5/166 LS4 can support up to 768MB of error-correcting code (ECC) parity memory; one card (64MB standard) comes with the stock configuration. The ECC memory has a high level of redundancy, so most hardware failures will be transparent to end users. While the system stays up and running during such a problem, the system administrator is notified of the fault. You can use the supplied diagnostic utilities to determine the location of the bad memory module and replace it during the server'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 architecture where both PCI buses talk to the system bus, providing a full range of PCI capabilities. Each PCI bus is 32 bits wide with a bandwidth of 132 Mbits per second (Mbps). This design allows for more PCI slots without the slowdown of a bridge architecture. You can separate devices of differing speeds to optimize the performance of your system. For example, you can separate your slow network cards from your fast SCSI controllers. Five PCI slots are on the single- and dual-processor systems, but only four slots are available in the quad-processor version--the extra processor card blocks one slot.

Dual PCI Fast and Wide SCSI-2 controllers are embedded on the motherboard--equivalent to two Adaptec 2940W controller cards--giving you a multitude of storage options. The NetServer LS has out-of-the-box RAID mirroring and duplexing without any extra hardware because of the two embedded controllers. For example, you can configure your system for fault tolerance in the 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 hold up to six half-height 3.50" hot-swap drives: Each bus can control three drives, 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 can use a single hard drive that holds the operating system, on one embedded controller (install the drive in the common 5.25" bay) and run the RAID drives for data only, on the remaining controller. Or, you can put the six hot-swap drives on one bus and use the second bus for an external storage subsystem holding up to an additional 25GB. The system supports fully hot-swappable disks if you use HP drives, and you have an option for RAID 6 via a PCI RAID disk-array controller. The performance depends on your data mix, so you 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 faster than software-based RAID on the rebuild, and the performance hit during the failure 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 a standard 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 EISA SVGA controller from Cirrus Logic, with 512KB of DRAM, upgradeable to 1MB.

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

To test the NetServer's SMP performance, we ran a custom Adobe Photoshop script on one, two, three, and all four processors. Each additional CPU improved processing about 40%. The extra megabyte of Level 2 cache per processor makes all 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's separate 1MB Level 2 caches. The NetServer's SMP architecture should mean that as 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 reduce the cost of ownership and maintenance. On the hardware side, the NetServer has everything from a specialized data bus for querying hardware to a single-board computer that you can add for remote control. On the software side, HP ships the Navigator CD, which contains several assistants to simplify system administration. A floppy disk taped to the inside of the computer's cabinet provides utilities to diagnose failures and suggest fixes in the event of a total system crash.

Beyond the ECC memory and hot-swappable RAID drives, HP built in hardware-reliability and -testing capabilities with its proprietary I-squared C-Bus. This simple, low-speed, three-wire serial bus connects the CPU to disks and other peripherals, so you can manage the system. With sensors for conditions such as operating temperature and voltage, the system logs failures to non-volatile RAM (NVRAM) for later access. The software on the Navigator CD or the utilities on the special boot floppy can read the log. Moreover, using this bus, the operating system can interrogate the system and report failures to the administrator.

An interesting option on the NetServer is the Remote Assistant, a hardware add-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 EISA buses and main power) watching temperature, voltage, and other system parameters. HP says this card is for "out-of-band management" because the system can suffer a complete failure, and without being anywhere near the console, an administrator can still use a terminal emulator to dial in to the board from anywhere and work on the system.

When the Remote Assistant Card detects a failure, it either sends out a network 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--to manage 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, the system automatically captures the console screen into NVRAM, so that you can view the image. From any error messages, you can determine why the system halted. Screen 1 shows the Remote Assistant, which lets you power up remotely after 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 is ANSI-compatible, so a program such as ProComm will work, but it will lack certain features. The Remote Assistant software has macros tailored specifically to features on the card, and it supports control codes such as Ctrl-Alt-Del and Alt-F8 for performing system functions: You can enter the EISA configuration utility to set up cards and peripherals, use the CMOS setup routines, and reboot the system. Macros can, among other things, send character strings to remotely boot and log on to the server or to monitor bus statistics and usage, as screen 2 illustrates. However, the Remote Assistant card is not an independent modem and will not function as an ordinary dial-in port. You need a separate modem to do ordinary server maintenance through NT.

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

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

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

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

NetServer 5/166 LS4
Hewlett-Packard
Fax-back system: 800-333-3500
Price:As tested: $33,676; 166-MHz quad-processor upgrade from 133-MHz system: $17,278; Remote Assistant Card: $895