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Ask Dr. Bob Your NT Questions - 01 Feb 1997

Send us your tips and questions. You can also visit Bob Chronister's online Tricks & Traps at http://www.winntmag.com/forums/index.html.

Q: I've seen many discussions about the use of symmetric multiprocessing (SMP) in Windows NT. Many users favor it, but many say that it's actually slower than using one processor. Which is correct?

Both sides are correct. Many factors enter into the use of SMP. Most systems use the Intel SMP configuration (MPS 1.4), but many use OEM-specific hardware abstraction layers (HALs) optimized for specific motherboards. The latter systems tend to work better than the generic MPS 1.4 HALs. In the race to be different, a board manufacturer will often add or change features that are not compatible with the MPS 1.4 specification. These changes can diminish the SMP performance.

In both standard and OEM-equipped SMP machines, the ultimate performance depends on which application you're using. SMP balances a load symmetrically (i.e., across all processors). The specific thread characteristics of the application affect the load balancing. If the application is not thread aware (which usually means the vender never tested the application on an SMP machine), an SMP machine will not perform as well as a single-processor machine. Screen 1 shows an application (U-Lead's Photoimpact SE version 3.0) that is poorly threaded. Notice that the workload does not appear to be symmetrical; in fact, the CPUs appear to be antagonistic toward one another (i.e., the thread bounces from one CPU to the other). In contrast, Screen 2 shows an application (Picture Publisher for NT, which unfortunately was never developed into a full product) that is very thread aware. The CPUs are in total synchronization and complete the work much faster than a single-processor machine.

Caution: A friend recently purchased a dual 200MHz Pentium Pro with a SuperMicro motherboard. He added an Intel Pro 10/100 NIC and decided to repartition his hard disk. NT saw only one CPU. When he removed the Intel NIC and installed a 3Com XL card, the system recognized both CPUs. Be aware that certain NICs can conflict with the Advanced Programming Interrupt Controller (APIC) logic in the SMP machines.

Q: How do image backups compare to standard file backups? Is this a way for backup vendors to get us to buy new software?

Mainframes have used image backups for many years, but file backups are more recent. In general, an image backup works with the sectors on a disk and is independent of the sector content. An image backup includes information about partition tables, file tables (FAT, MFT, etc.), and the Master Boot Record. File backups contain information about files and their attributes. In a file backup, you can selectively restore individual files, whereas in an image or sector backup, you have to basically restore the entire drive.

Both types of backups have advantages. The file backup lets you restore individual files and directories but will not regenerate a drive. The image backup lets you boot to a set of floppies and restore the contents of a tape, thus regenerating your drive. However, the size of the drive you restore to must be at least equal to the size of the drive that you back up. In fact, an image backup works best when you use identical drives. In all cases, you need to perform a low-level format on the drives to optimize the restore. You do not need to partition or format the recipient drive. As you might expect, you can't do an incremental sector backup, so image backup is better for true disaster recovery and file backups are better for individual file restoration. As of this writing, only ARCserve and ULTRABAC offer both image and file backup software for NT.

Q: My colleague wants to use a print server on a small NT LAN. He claims he can set up the print server as a TCP/IP device, which will offer great advantages to the LAN. What is a print server, and how do you configure it as a TCP/IP device?

Print servers are small devices that connect directly to a network hub or switch. I am aware of only servers that function with 10Base-T and 10Base-2 connections. The print server I have the most experience with is the Axis 560. This device has two parallel connections and one serial connection. You simply power the device after you connect it to the switch or hub. From this point, the setup becomes an NT and print-server issue. On the NT side, you need to add Microsoft TCP/IP Printing under the Services tab of the Network applet and FTP under the Internet Information Server Installation applet.

Step one: Place a printer on the first parallel port (PR1), and print a test page. This page will most likely give you the printer's current settings. The one to notice is the IP address, which is 192.36.253.80. Unless you have a router or some means of accessing the device, you need to change the device's IP address.

Step two: Decide which machine will control the print server. The Backup Domain Controller (BDC) is a logical candidate. You can use a workstation for the print server, but this approach limits you to only 10 simultaneous connections. Go to the Network applet and change to the IP address of the designated machine. This step is not a major issue because you won't have to reboot. Within the subnet of the print server's IP address, choose an address such as 192.36.253.82. After you apply this new address, type

PING 192.36.253.80

at the command prompt and press Enter. Make sure you can ping the print server before continuing to step three.

Step three: At the command prompt, type

FTP 192.36.253.80

and press Enter. You will connect, as you see in Screen 3, and receive a prompt for user name and password. The default settings for Axis print servers are root (as user) and pass (as password). After you establish a connection, you need to access the configuration file. Type

get config

and press Enter. The configuration file, config, will be in the root directory.

Step four: Open config in Notepad, as you see in Screen 4. Change to a unique IP address on the print server's subnet by changing the address listed, and save the config file. Upload the config file to the print server by typing

put config CONFIG

and pressing Enter, as Screen 3 illustrates. Print a new test page. The new test page will show the new IP address. Use the Network applet under the Control Panel to return the machine's IP address to its original address.

Step five: Create a new printer on the machine that controls the print server. This printer will be a local printer. Using the standard add printer wizard, add a new LPR port, which you see in Screen 5. When you see the prompt to enter the name or IP address of the print server, enter the IP address you assigned the server. For the name of the printer, enter the print port or the print server where the printer is connected (e.g., PR1 or PR2). Choose the printer type and load the appropriate driver. You then simply share the printer as a standard printer share. Screen 6 shows the new PR port highlighted.

The server will work well on the network. However, be aware that any printing on the network will tie up the controlling machine. Each print request will cause major CPU utilization, as you see in Screen 7. For occasional print jobs, you can specify the controller as any machine on the network. For a serious print server, dedicate a machine.

Q: I have a question about the Queue Length counter that you can enable in NT's Performance Monitor. Do you have to monitor at least one thread counter to keep the counter from always showing 0?

The System:Processor Queue Length counter is an important tool for monitoring excessive threads. A lot of multitasking can generate an excessive amount of threads and produce a bottleneck. In NT 3.5, you must monitor at least one thread for the counter not to read 0, but in NT 3.51 and 4.0, you do not need to monitor a thread.

Q: I am trying to do unattended installations, but I can't figure out how to turn off the End User License Agreement (EULA). If I can't turn it off, I can't perform unattended installations in NT 4.0.

Believe it or not, you can turn off the EULA. However, you need to be aware of the consequences. Microsoft wants everyone to see the EULA and agree to it, whether they read it or not. If you turn the agreement off, you are violating Microsoft's intent. This action is not a major issue because you can print out the EULA and give the hard copy to the machine's user. To turn the EULA off during unattended installations, you need to add the following statement in the unattended section of your answer file (unattend.txt by default):

\[Unattended\]

OEMSkipEULA=yes

Q: I am interested in adding modems and ports to our company server. Unfortunately, the advertising for such products is very confusing. How do I know what type of device to buy or know what is available for use?

You can take at least three different approaches, from the simple to the powerful.

1. Add a Standard Multiple-COM Port Card

Several vendors, including Boca Research and STB Systems, make multi-COM port cards. If you have enough open IRQs, these cards work well. However, be aware that communications servers are generally resource intensive, and they lack some serious communications server features: For example, they don't reduce CPU workload.

2. Add Intelligent Multiple COM Port Cards with Onboard Processors

An intelligent multi-COM port card with an onboard processor can reduce CPU workload. An example of such a card is the Digi International PC/2e board, which you add in the Network applet in Control Panel. Once you assign a memory base and I/O base and reboot the system, the card is ready to use. Screen 8 shows an example of a successful configuration with two COM ports available. Using these cards with full-sized modems or with numerous modems can easily become a hardware nightmare because of the size of the setup and the amount of cabling required.

3. Add Modem Servers That Use PC Card Modems

Modem servers with PC Card modems are small and easy to manage. Two types of these servers exist. The first type is a network server that uses either TCP/IP or IPX/SPX to attach to a network, and the second type is a SCSI device that works off a special driver.

Digi's LANAserver 6e is an example of the first type of modem server. This server has six COM ports and is easy to configure. I set up one to work with TCP/IP. You simply run an onboard main menu and add the IP address and subnet mask. The board then resets, and you can easily PING it. Install the LANAserver application and configure the server on the network. Interestingly, the program adds a layer of security to the system--you must pass the server security to gain access to NT's built-in security. Screen 9 shows the security window.

After you set up the system, all modems are visible in the LANAserver Manager, as you see in Screen 10. You can then edit each port for type of card (LANAserver can use Integrated Services Digital Network--ISDN). The modem server's design is very impressive, and because it is a peripheral server, it considerably reduces the workload from system CPU.

Despite these promising features, Digi does have a few problems to work through. For example, the server expects to load IPX/SPX. If IPX is loaded, you can dial out from any node on the network. Unfortunately, you can't dial out with NT, but Digi assured me that NT support is in the works.

Another type of server is Central Data's equally elegant SCSI-based ST-1008+ communications server. You assign this server an unoccupied SCSI ID and connect it to a SCSI controller (I used an Adaptec 3940 with firmware 1.14). After you reboot the system, you load a driver through an easy-to-follow standard setup. Screen 11 shows the Central Data driver loaded in the Devices applet under the Control Panel. Unlike Digi's LANAserver, Central Data's communications server considers each of its ports as a standard COM port and lets you configure the server through dial-up networking or Remote Access Service (RAS). Screen 12 shows the eight PC Card slots added as ports in the Port applet under the Control Panel. (As a side note, Central Data also offers IP-based servers.)

The obvious advantage of Central Data's ST-1008+ server is the use of a SCSI busmaster to off-load CPU work. It is an elegant approach to a communications server.

All these devices have clear-cut advantages and disadvantages. The four-port card is inexpensive but CPU-intensive. For moderate access, the coprocessed cards are excellent choices. For intensive use, the Central Data and Digi servers are well worth consideration.

Q: I recently purchased a 3Com Impact IQ ISDN device. All the instructions focus on NT 3.51. How do I configure it for NT 4.0?

Installing your 3COM ISDN device for NT 4.0 is simple. Ignore everything about setting up the device with NT 3.51 RAS. Go to the Modems applet under the Control Panel. Click on the button to add a new modem, and tell the system that you will select the device from the list (i.e., do not autodetect the device). Choose Have Disk, and insert the 3Com driver floppy in the drive. When the system presents you with a list of 3Com modems, select the 230 (even though most Internet Service Providers--ISPs--don't support compression now, they may in the future). The rest of the process is automatic. Reboot the system. The only caveat to using any ISDN device on a serial port is the ability of that port to support high-speed connections. I strongly recommend a Digi board (or another supported coprocessed card) for the connection.

Q: Like all systems administrators, I'm concerned about protecting systems from data loss and failure. I know of one system that got a boot sector virus, and the whole drive was lost when the boot sector was repaired. Can I protect my systems from this type of situation?

I've been working on this issue for quite some time. First, this situation is not so grim if you're prepared for it. You can easily recover from this type of data loss if you have a simple set of tools.

1. Always have an up-to-date Emergency Repair Disk handy. Always run rdisk /s after major changes to the system.

2. Always have a recent backup available--not having one is almost computer malpractice. Backup applications are becoming cheap and plentiful. I recently looked at McAfee's QuickBackup. Although it ostensibly functions in NT 4.0, you can back up to a remote FTP server or to a hard drive, but a backup to tape won't work. Interestingly, the cost of the program is less than $50. Now you have no excuse for not having a backup handy.

3. Make an NT boot floppy. Most people think a boot floppy is one that allows only DOS booting, but you can also have an NT boot floppy. It is similar to a DOS boot floppy, but easier to make. The beauty is that you can make an NT boot floppy on any NT machine (if you are on the same platform). The only variable is boot.ini.

Format a 3.5" floppy in NT (File Manager is still the easiest application way). Copy ntldr and ntdetect.com to the floppy. I usually make sure I'm using standard file attributes before copying these files because standard attributes make the files easier to work with. Copy boot.ini to the disk. ntldr and ntdetect.com can come from any machine, but boot.ini is machine specific (so make sure you have a copy of boot.ini handy to copy to the floppy). Don't worry about copying bootsect.dos. Because obtaining a DOS boot floppy is easy and bootsect.dos is machine specific, use a DOS boot floppy.

4. Every serious NT machine needs at least two hard disks. Pick one as your main disk and one as a secondary disk. Place a copy of NT on each disk. Although it sounds like work, this configuration can be a godsend. If the primary NT system fails, you can always boot to the secondary one to repair the primary one.

5. Make sure you have the NT boot floppies. If you don't, run either winnt /ox or winnt32 /ox (you can run the first from DOS or Windows 95, the second from NT, or both from the appropriate folder on the NT CD-ROM).

After you finish these five steps, you're prepared for nearly any disaster. Let's look at two examples.

You Have a Corrupt Boot Sector

Boot to the NT boot floppy, and you will have the same NT options you had before the corruption. You can gain access to critical files and make a backup if necessary. After you've taken these steps, you can try repairing the boot sector. If the repair does not succeed, you still have saved all the critical data.

You Get an Event Viewer Message That a Hard Disk Is Failing

Back up the failing disk. Turn the system off, remove the bad disk, and replace it with a new one. Insert the boot floppy, and boot to the copy of NT on the remaining disk. You can open Disk Administrator and format the new disk and then restore files.

Screen 13 shows a normal setup. Disk 0 has three partitions. NT 4.0 was installed on Drive E and Drive H. Disk 0 was removed and replaced with a blank drive. The system was booted to NT on Drive H. Screen 14 shows Disk 0 as being blank. This situation is easy to fix. Restore the backup of the lost disk onto a new one. Boot to the first installation floppy, and run a repair of the boot sector. This total process will take about 30 minutes depending on the size of the drive. (Alternatively, you can back up and restore a sector. This method is faster but not necessarily as up to date.

Boca Research
561-997-6227
Web: http://www.bocaresearch.com
STB Systems
972-234-8750
Web: http://www.stb.com
LANAserver 6e
Digi International * 612-912-3444 or 800-344-4273
Web: http://www.digiboard.com
Price: $2895; (PC/2e Board $299)
ST-1008+ scsiTerminal Server
Central Data * 217-359-8010 or 800-482-0315
Web: http://www.cd.com
Email: [email protected]
Price: $995
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