Welcome to BayPoint Systems

The NT Server supports a replication service that causes the server to automatically copy files into the repl directory. When you have the Server running on a network, you place your script files in its export directory and they end up in this import directory on the target machines. Forcing you to put these scripts in these directory prepares you for the day when the replication service starts working on your network.The book describes how to set up the replicator on your server.

When I disconnect a machine from the network and try to run it stand-alone, it will not boot. Why?

If the machine has an Ethernet network adapter installed, try attaching a terminating resistor to the BNC connector on the card.

I've given EVERYONE permission to access a certain directory or printer, but certain users get "permission denied" messages. Why?

The EVERYONE group uses the Guest accounts on all of the different machines to authenticate users. For example, say Mary tries to connect to a disk that has EVERYONE permissions, but the machine holding the disk does not have an account for Mary. What NT will try to do is let Mary's machine log in under the Guest account. If either machine does not have a guest account, or if the guest account on either machine is disabled, or if the guest accounts on the two machines have different passwords, the authentication will fail and Mary won't be able to connect.

I have a machine that has no network card installed, but I want to configure it for use with RAS. How do I do that?

When you first install NT, it will get to the network portion of the install and it will try to detect the network card. Let it do that automatically, and it will come to the realization that there is no network card and give you a "remote" option. At that point select the remote option and you should be OK. Just set up the modem with the RAS server and then set up the client to dial, and you are ready to go.

When we first did our NT installation on a Gateway Nomad, we had a normal mouse hooked to COM1. When the installation program got to the "remote network" part, it looked out and saw the mouse on COM1, realized there was no COM2, and then aborted the net installation halfway through. This left the system in an awkward state network-wise when NT booted, and RAS would not work. I diddled with this for about 2 hours. When I looked in the event log, I got an error on the NetBEUI portion, so in the network applet of the Control Panel I removed the NetBEUI portion and reinstalled it. Then I got an error in the NetBIOS portion, so I removed and reinstalled it. Then I got an error in the workstation portion. I removed and reinstalled it. But then a funny thing happened--when I rebooted and came back and clicked the network applet in the Control Panel, NT automatically brought up Windows NT Setup and proceeded to completely reinstall the network portion. This time, since I had no mouse connected, everything went OK and RAS worked fine.

It was the removal of the Workstation portion that triggered the reinstallation. If you are having problems with your network, one easy way is to eliminate everything in the network applet of the Control Panel and start over from scratch.

I try to run Microsoft Works (16-bit version) under NT, but when I try to print to a network printer I get an "invalid port" message because the port is NET:. Is there a work- around?

Printing works fine from Microsoft Word, but not from Works. You might try looking for a later version of the product, or simply switch over to Word, or print from a local printer.

A user of mine typed "telnet" and it said "contact your system administrator", so he contacted me. What do I do now?

You need to install the TCP/IP portion of the network services in the Network applet of the Control Panel. Look at chapter 14 of the book , which discusses the installation of the TCP/IP module. That module is required for the telnet command to work. Once you install and configure the TCP/IP module, telnet will work.

How can I send a message to one user, or all users, on the network?

First, you have to make sure that the "messenger" service is automatically starting on all workstations on the net. See the Services applet in the Control Panel and check the settings (see also Chapter 7). Then you can say:
net send name "message"

Where "name" is the name of a machine or a user, and "message" (in quotes as shown) is your message. To broadcast a message say: net send * "message". For more information, type: net help send at the command line.

When I work from home I use RAS, and I would like for it to connect automatically whenever I log in. How can I do that?

There is a command called "rasdial" that you can use. Type "rasdial /?" for more information on parameters. Add it to your login script.

I am using WfWG ver. 3.11, and want to use RAS to connect to my NT machine with a modem (or null-modem cable). However, the maximum speed seems to be 9600 bps. Is there a way to speed things up?

If you try to connect WfWG to NT via RAS with a null-modem cable and it does not work, then you probably have the speeds for the NT server and RAS clients out of sync. Once they match, it should connect provided all the cabling is correct. You set the speed in NT in the Network applet of the Control Panel. In WfWG, you set the speed by clicking the "edit" button for the null-modem entry and then clicking the "modem" button and changing the "Initial Speed". If the Initial Speed seems to be limitted to 9600 bps, exit WfWG and edit the file named serial.ini. Change both the MAXCARRIERBPS and MAXCONNECTBPS entries to 38400.

How much memory does an NT machine really need to be "comfortable"?

It depends on what kind of machine it is and what the machine is doing, but we can give you some feedback from personal experience in our office. In our office we have 486-and Pentium-based PCs running NT 3.51 workstation and server. We do a lot of compiling with Visual C++. We also do a lot of word processing with Microsoft Word ver 6.0. To do that, you need at least 16 meg. However, 24 meg is where NT is "comfortable" when compiling and for many other activities. For example, to insert a drawing in a microsoft Word document with 16 meg takes 30 seconds, but with 24 meg it takes 7. There is not a tremendous improvement if you add any more. 24 meg is therefore, in our experience, a good low-end number to shoot for. 32 meg is a good round number to shoot for. Also note that if you have to decide between spending money on memory or a faster CPU, memory will have a much bigger effect if you are currently at or below 16 meg of RAM.

For the NT server, start with 32 meg of RAM and work from there. For all NT machines, the more memory the merrier. 48 meg is not unreasonable if you are doing a lot of compiling. On a server machine more memory means better caching, which improves performance (especially if the SQL server is running).

I have a user who has been running Microsoft Word without difficulty for the past month. Today when the user starts Word 2.0 it dies with a "divide by zero" error. When he runs Word 6.0 it gives an application error. What is wrong?

Try shutting down and rebooting the machine. Something has become corrupted in the 16- bit subsystem.

12) I have created a new group called "Students" and then created new accounts that are members of that group only. I gave the Students group only the right to Log On Locally. However, students are still allowed to shutdown the machine. Since I haven't given them the right to shut down, why are they able to do it?

If you look at the shutdown right in the User Rights dialog of the Policies menu of the User Manager, you will see that the group Everyone has the right to shut down the machine. You should eliminate Everyone from that right.

How can you find out who are the members of a particular group in the User Manager?

Use the Properties option of the Users menu of the User Manager.

How can I administer the account list of another machine on my network? For example, I have a peer-to-peer network and I want to administrate all of the account lists from my machine without having to walk around to each one?

In the Resource Kit you will find the User Manager For Domains (or if you have the Server it contains the same tool). In the User menu there should is a Select Domain option. If you type "\\machinename" into the domain area you will be able to edit the local account list on the machine named "\\machinename". You can run the User Manager for Domains on any NT machine.

When I select certain physical disk counters in the performance monitor they remain at zero at all times. Why?

Open an NT command prompt and type "diskperf -Y", and then shutdown and reboot the machine. This will turn on the disk counters but degrade performance by 2%-3%.

No security events are appearing in the security portion of the event log. How do I fix this?

Three things must happen for security logs to work: 1) The Event Logging service must be turned on in the Services applet of the Control Panel, 2) The Audit portion of the User Manager must be turned on, and 3) You must select security events in the User Manager, File Manager, Registry Editor or Print Manager. Use the Audit option in the Security menus of the different programs to enable the security events you want to monitor. You must enable security logging in the User Manager.

When I use the "net send" command to send messages to another user, the user never receives the message. What is causing this problem?

Usually this problem is solved by turning on the Alerter and Messenger services in the Server applet of the Control Panel. Also, make sure the user is not logged in on another machine. If the user is logged in more than once, only the machine first logged into gets the message.

The "at" command does not work properly. What causes this problem?

Usually this problem is solved by turning on the Schedule service in the Server applet of the Control Panel.

I need to add 20 accounts to the system. Is there an easy to do this?

Set up an account template and then copy that template to create each new account. The new accounts will receive all of the attributes of the template, and then you can modify the user specific information such as user ID, user name/description, and password.

A template is simply a normal account that does not contain a user name. Give it a generic ID such as "sales" or "accting". Then use the Copy option in the User menu to copy it.

I need to add 200 accounts to the system. Is there an easy to do this?

If you need to add 200 accounts, the use of the graphical User Manager can be cumbersome. In this case you will probably want to create a program or script the uses the "net users" command to create new accounts.

I have a shared directory (or FTP server) on my machine, and so many people are connecting to it that the machine is totally bogged down. Is there a way to control the load on my machine?

In both the FTP server and the File Manager's Share As dialog, you can specify the maximum number of connections allowed. Use this feature to keep connections to a reasonable level.

How do I change the PATH and other environment variables for all of my users?

Use the Registry Editor (regedt32.exe) to change the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment key. Add your new variables and/or change existing variables here.

I get a message about a full event log file when I log in. How do I clear out the event log? How do I archive the events?

The evnt log has a Clear Log option that clears events from each of the three different logs. Before clearing, it will ask you if you want to save the events. Save the events and then preserve that file on disk or tape. Be sure to save each log to a separate archive file, and name the file so you can later restore it to the proper log.

I've forgotten the administrative password. What can I do?

If you have an emergency repair disk for the machine, you can reload the SAM database. This will return the machine to the account situation you had just after createion. This configuration will have two or three accounts (administrator, guest, and possibly a user account). These accounts will have the passwords you gave them during installation, and you will lose all other accounts. If you cannot remember the admin password on the emergency repair disk (or if you do not have an emergency repair disk), then you will have to reinstall NT using the install disks.

Should I use the FAT or the NT File System?

You should not use the FAT file system unless you have to. The NT File System is secure and much more robust. The only reason for using a FAT file system is because you need to have both DOS and NT on the same machine in a dual boot configuration. If you have a FAT partition that you want to convert to NTFS, see the CONVERT command in the NT Command Prompt.

I want to be able to log in on different machines and have my account information come to that machine. How do I make my account follow me around?

First you need an NT Server acting as a domain controller on your network. This will centralize your account list. Second you need to use the NTAS Profile Editor to create a personal profile for yourself and store it in a central place. The profile will hold all of your personal information like colors, fonts, etc. Because it is stored centrally by the profile editor, it can move around. See the book for more information on profiles. You will probably want to locate your home directory and email information centrally as well.

How do I find out what all keys in the registry mean?

Look in the regentry.hlp file in the resource kit.

How do I display a legal notice whenever anyone logs in?

In the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon key add two keys of type REG_SZ named "LegalNoticeCaption" and "LegalNoticeText" to act as the dialog title and body respectively.

I am trying to use mail in NT, and for some reason it has "jammed". I get error messages when I try to send mail, or it says it cannot find the post office. How can I fix it?

If you have WfWG machines on your net, it is probable that one of them has hung. If you go quit mail and schedule+ on all machines and then restart, that will solve the problem. Rebooting the postoffice machine will not solve the problem.

I normally use Windows NT at the office, but I have a Windows for Workgroups on the portable that I use on the road. I want to RAS in and access the post office that is on an NT machine so I can check my email. When I dial via RAS, I log in using my normal NT logon ID and password. I get in fine. However, I cannot connect to the post office--it says "access denied" when I double-click on the machine holding the post office. What is happening, and how do I get around the problem?

There is a problem (feature?) in the authentication process when you log in to an NT network from a WfWG machine. Because you logged in as a specific user (rather than "guest"), it does not understand that you are a member of the group "everyone". Therefore, it will not let you connect to the NT machine using the browser. However, if you type the path directly (e.g. "\\NTAS\wgpo"), it will ask you for the password and then let you connect. After that initial connect, subsequent connections will be transparent.

Is there any way to look at a DoubleSpace FAT partition with NT?

There is, as yet, no way to look at a DoubleSpace or Stacker partition from NT.

I've just copied about 50 meg of files from a FAT partition to an NTFS partition. When I try to change the permissions, though, two of the files are "corrupt" and I get a message about them. When I try to delete them they won't delete either. How do I fix these two files?

Run "chkdsk /f" to check the NTFS partition and repair corrupt files, and then reboot the system. The corrupt files will be deleted automatically.

I have an NTS machine acting as my file server and name server for my NT users on the network. Each user's home directory is on this machine in a large NTFS volume set. Permissions are set so that all home directories are private to their users, and a number of other shared directories on this machine are secured by approporiate group permissions. Now that everything is locked down correctly with permissions, however, my Windows for Workgroups users cannot get into anything. How do I allow them to access a secured NT server?

In the Network applet of the Control Panel on the WfWG machines, there is a Startup button. In its dialog is a place where you can have WfWG authenticate its user again the domain's name list. Once a user has been authenticated by the domain, he/she can use the secured NT server just like an NT user, and will be able to get at files on which he/she has access permissions. For this to work in a secure manner, you have to get your WfWG users in the habit of logging on and off using the logon icon in the Network group of the Program Manager.

I have an NT machine and the user has locked the workstation. Besides turning the machine off and back on, how do I log them out so someone else can use the machine?

If you log in to the "Unlock Workstation" dialog as the administrator (or under any account that has administrator privleges), NT will warn you and then log out the user.

The login box on any NT 3.5 machine has a shutdown button. What if I don't want people to be able to randomly shutdown the machine?

Set the registry key HKEY_LOCAL_MACHINE\Software/Microsoft/Windows NT/CurrentVersion/WinLogon/ShutdownWithoutLogon to zero.

How do I synchronize the time on my NT machine with the domain controller or another NT machine?

Type the following command: net time \\nts /set . Where nts is the name of the NT machine with which tou want to synchronize.

I have a modem that I want to use for RAS. However, the modem is not listed in the list of RAS modems and none of the seemingly compatible modems I have tried in that list work. What do I do?

If you have a manual for the modem that lists all of its AT commands, you can make a new entry for your modem by changing the MODEM.INF file. This file is a normal text file that lists all of the modem characteristics for all of the modems known to RAS. For example, we purchased Winbook portables and their modems did not work in RAS. We added the following to the MODEM.INF file:

[WINBOOK Internal]
<speaker_on>=M1
<speaker_off>=M0
<hwflowcontrol_on>=\\Q3
<hwflowcontrol_off>=\\Q0
<compression_on>=%C1
<compression_off>=%C0
<protocol_on>=\\N3
<protocol_off>=\\N0
<autodial_on>=ATDT
<autodial_off>=ATD

CALLBACKTIME=10
DEFAULTOFF=compression
MAXCARRIERBPS=14400
MAXCONNECTBPS=38400

DETECT_STRING=ATI4<cr>
DETECT_RESPONSE=3710
DETECT_RESPONSE=3721

COMMAND_INIT=AT&F&C1&D2 V1 X4 S0=0 S2=128 S7=55 S8=6<cr>
COMMAND_INIT=AT<hwflowcontrol><compression><protocol><speaker><cr>
COMMAND_LISTEN=ATS0=1<cr>
COMMAND_DIAL=<autodial><phonenumber><cr>

Simply look in your manual for the modem and fill in all of the blanks. If a blank does not make sense, look for other modems in the file and compare. Also, as a general rule, do not try running the modem at faster than its rated baud rate if you are using software compression. If it is a 14.4 modem, set up the baud rate at 14.4.

I have tried and tried to get an NT machine to connect on the network and it just will not work. The other machines on the network work fine. What can I do?

Try this: start over! Many times, the settings get so mangled that it is impossible to get things set up. First, make sure the cabling is OK by substituting a working NT machine in place of the one having the problem. Also confirm that the network card is OK by trying it in a different machine. Then go into the problem machine, open the Network applet in the Control Panel, and remove everything, including all device drivers for the network card. Then reboot the machine. Now when you go back into the Network applet it will ask if you want to install the network drivers. Do it, but install only the NetBEUI protocol. This is the simplest protocol and therefore has the highest probability of success. See if that protocol can see the rest of the network by trying to connect to something in the File Manager. That will almost certainly work unless there are hardware problems. Now add in the other pieces incrementally and you are set.

I have Macs on my network, and I have heard they can print through the NT server but I am skeptical. Does that really work? What if I do not have a PostScript printer on the server?

As hard to belive as it seems, this part works extremely well, and it still works even if you have non-PostScript printers connected to the server. For example, we have a PowerMac hooked to our NT network. The server has the Mac services loaded, and is connected to an HP-compatible printer (an Epson ActionLaser 1500, to be exact). You can open the Mac's Chooser and see the printer in the PSPrinter list. When you print to it the Mac spools extremely quickly (23 pages in 10 seconds). In one test we printed a 23 page chapter from FrameMaker on the Mac. All fonts, graphics and bitmaps were translated exactly as you would expect. It took 5 minutes and 30 seconds to print the 23 pages (it is a 6 PPM printer), so there is about 1:30 overhead. The server is working pretty hard during the process, presumably translating the PostScript.

Is there a way to create an emergency repair disk (ERD) after installation? Or what if I add 50 accounts to my machine - how do I get that information onto my existing repair disk in case the machine goes down?

You can create a new ERD or update an existing one with the NT command RDISK. Type this command at a command prompt.

My company has a mixed NT/UNIX network. We have satellite offices which have NT machines that are connected to the Internet. Because they are on the Internet, people in these satellite offices can telnet to the UNIX machines in the main office, but they can't do much else. Is there a way for them to hook into drives and printers of other NT machines? I don't want to use RAS to do this because the long distance charges would be huge.

You can use the Internet as your WAN, and people in the satellite offices can connect to both drives and printers in the main office. To do this you modify the LMHOSTS file and tell it the IP addresses of the machines that you want to connect to. Look in SYSTEM32\DRIVERS\ETC for a file named LMHOSTS.SAM. Save it as LMHOSTS in the same directory and make your changes there. Make sure the LMHOSTS capability is enabled in the Advanced portion of the TCP/IP setup dialog in the Network applet of the Control Panel. Now add IP addresses and machine names to the LMHOSTS file. For example, if there is an NT machine at 152.5.94.36 whose name in the office is SERVER3, add the following line to the LMHOSTS file:

152.5.94.36 SERVER3

Now the user can type on the command line (immediately - no rebooting required) the following command: net view \\server3

The user should see a complete list of drives and printers available on that server. Let's say that one of the drives is called CD-ROM. The user can then go to the File Manager and select the Connect option. Server3 will not appear in the list, but the user can type \\SERVER3\CD-ROM for the path and his or her user name in the Connect As field. The drive will connect up just like any other.

Note that ANYONE on the Internet can connect up to ANY drive on your network in this manner. All they need to know is the IP address of the machine. You will want to make very sure that every drive and printer on your net has been secured properly or you have a very large security hole. Putting a domain controller on your network is the best way to do this.

How can I clone an NT machine? That is, I have an NT machine in my office. I want to back it up on tape, fly across the country, load the tape on a new machine and see something exactly like the machine in my office. The problem is, when I load the tape on the new machine, it recovers the entire registry. I need the registry because my accounts, preferences, etc. are in there. However, the registry also contains the hardware configuration of my office machine, and when that gets loaded on the new machine that machine fails to boot because of the hardware differences. How do I get around this problem?

Try this. On the new machine, load NT. Be sure to make an ERD. Now load the tape. This will give you a machine that will not boot because of the registry problems. Now boot off of the installation diskette. Choose the repair option. You will be able to repair the registry, and pick which portion of the registry that you want to repair. You want to repair just the SYSTEM portion. When you perform this repair, the system will load the hardware configuration off of the ERD and this should recover the correct registry settings for the new hardware. Reboot and you should have a clone.
This is not guaranteed to work in all cases. Try it before you bet your life or career on it.

How do I change the drive letter on a drive or a CD-ROM drive?

The Disk Administrator in the Administrative Tools group of the Program Manager contains the tools to change drive letters. There is a menu option that is always available to change CD-ROM drive letters. If you click on a particular partition a menu option will appear that lets you change the partition's drive letter.

I have a portable that I use in a docking station. The docking station contains a CD-ROM drive. I have loaded NT and it works fine. However, when I pull the machine out of the docking station and reboot it, it blue-screens on me complaining about a mising boot device. What is happening?

In general, it is currently better to run Windows 95 on a portable because it handles things like this more gracefully. The problem NT is having is that the CD-ROM drive is missing when you are not on the docking station. Put the machine back in the docking station and reboot. Go to the Windows NT Setup application in the Main group of the Program Manager. In the Options menu choose Add/Remove SCSI Adapters. Remove the CD-ROM drive from the list. The machine should now reboot properly off the docking station. When you want to use the CD, reinstall the driver.

I have a large NT network and use the NT server. If I want several admins to do remote administration, do I need to buy them the NT Server, or can I buy the NT Workstation? What about Windows 95 and WfWG machines? Can you administrate from them?

For remote administration you should buy the workstation product and get the resource kit. The resource kit includes the user manager for domains and other server-style admin tools. When you run them on the workstation product it can get to the servers remotely. The only reason to use the server product is to create a new domain or backup the name server on an existing domain (or because you need another RAS or disk server on the net).
When you install the server it creates a program group that has in it the "Network client administrator". Start it up and one choice is to create the regular Windows admin tools. Use those on WfWG machines.

I have UNIX machines on my network and want to be able to mount an NTFS drive letter from my NT server onto my UNIX machines using NFS. How do I do that?

Sunsoft sells a product called PCNFS that you run on an NT machine. It will allow you to mount NT volumes on a UNIX machine. NetManage sells a package called Cammelion that contains both the client and server sides of NFS. The Cammelion package also includes other useful tools like a telnet daemon for NT.

How do I schedule a job to run every day at midnight?

You can use the AT command in Windows NT. This command lets you schedule a command for execution at a specific time in the future, or to cycle the command repeatedly. A couple of cautions should e known before you use the AT command however: 1) you must start the Schedule service, 2) All commands that you run with AT will run under the account chosen for the Schedule service, and by default it runs at a system level which gives it access to everything, so you may want to change the account it runs under.

I need to write several scripts to help with system administration at my site. I don't have to use DOS batch files, do I?

No, you can use PERL instead and it is quite a bit more flexible. See the PERL tutorial for information on the language and how to obtain it on the net.

Side Effect of SP3 for Win NT 4.0

With Unencrypted Password SP3 Fails to Connect to SMB Server

Microsoft Article ID: Q166730
Creation Date: 10-APR-1997
Revision Date: 15-MAY-1997

The information in this article applies to:

Microsoft Windows NT Workstation version 4.0
Microsoft Windows NT Server version 4.0

SYMPTOMS

Connecting to SMB servers (such as Samba or Hewlett-Packard (HP) LM/X or LAN Manager for UNIX) with an unencrypted (plain text) password fails after you upgrade to Windows NT 4.0 Service Pack 3.

CAUSE

This is because the SMB redirector in Service Pack 3 handles unencrypted passwords differently than previous versions of Windows NT. Beginning with Service Pack 3, the SMB redirector does not send an unencrypted password unless you add a registry entry to enable unencrypted passwords.

RESOLUTION

To enable unencrypted (plain text) passwords, modify the registry in the following way:

WARNING: Using the registry editor incorrectly can cause serious, system- wide problems that may require you to reinstall Windows NT. Microsoft cannot guarantee that any problems resulting from the use of the registry editor can be solved. Use this tool at your own risk.

1. Run Registry Editor (Regedt32.exe).

2. From the HKEY_LOCAL_MACHINE subtree, go to the following key:

\system\currentcontrolset\services\rdr\parameters

3. Click Add Value on the Edit menu.

4. Add the following:

      Value Name: EnablePlainTextPassword
      Data Type: REG_DWORD
      Data: 1

5. Click OK and then quit Registry Editor.

6. Shut down and restart Windows NT.

You where asking about theScope ID in the WINS Configuration, as illustrated.

What is the Scope ID used for?

Microsoft states in its' quick help reference

The NetBIOS scope identifier is a string of characters used when network applications communicate using NetBIOS over TCP/IP (NBT). The NetBIOS scope identifier must be the same for all computers on a NetBIOS network using TCP/IP as the transport. If you have different scope identifiers on your computers, NetBIOS assumes they are part of a different logical network, and cannot connect to them.

In other words .... NBT(NetBIOS over TCP/IP) - specific information are the scope ID (limits communication between NBT hosts, it limits access and prevents the resources being offered by a system from being seen by systems with a different scope ID), and the location from which the LMHOSTS file should be imported.

Ordinarilly within a UNIX enviroment, you set the scope identifier when using the Network Configuration Manager to configure NetBIOS. Before setting it, check its value on the other machines in the network. If you have MS-DOS or OS/2 workstations on the network, the NetBIOS scope identifier should be set to NULL on all machines on the network. Many implementations of NetBIOS for TCP/IP allow you to use only the NULL scope identifier. If you have any other LAN Manager-compatible machines on the network, check their documentation for restrictions. Of course there are considerations. Is the server being connected to a WINS or a Samba server? The Scope ID acts as to further subdivide your particular workgroup into distinct units. Samba has no method of specifying a Scope ID, so this field needs to be blank (NULL); on a WINS server, this is not the case.

Here's some backfill for you:

NetBIOS and the associated protocol NetBEUI (NetBIOS Extended User Interface) have long been the basis of Microsoft's networking strategy.

Basic Input Output System (BIOS ):

It is the part of DOS that defines the I/O calls that applications use to request DOS I/O services. NetBIOS extends this to include calls that support I/O over a network. NetBIOS is an Application Programming Interface (API) that defines how an application program request services from the underlying network. NetBEUI includes the NetBIOS API, the Service Message Block (SMB) protocol, and the NetBIOS Frame (NBF) protocol. SMB is an API that defines how applications ask for network services, but NetBEUI is not just an API. It also includes the NBF protocol that builds NetBIOS frames for transmission over the network. NetBIOS is not just used to refer to the API, it is frequently used to refer to any network that uses NetBIOS.

NetBIOS requires very little memory and runs on any type of PC equipment (Geeze, I wunder why IBM wanted to use it? <G>).. It is a fast, lightweight protocol suitable for small LAN?s. NetBIOS is only suitable for LAN applications, it cannot be used by itself for a WAN or an enterprise network because it is a non-routable protocol (the protocol cannot be passed through routers, it can only be passed on a single physical network, it has no routing protocol and no independent address structure), and it depends on an underlying broadcast medium (it cannot be used over serial lines, point-to-point networks, or internets built from dissimilar physical networks).

NetBIOS over TCP/IP (NBT):

Is a standard protocol, by encapsulating the NetBIOS messages inside TCP/IP datagrams. It is based on the B-node (is a node that uses broadcast messages to register its name and to request the names of other systems on the network) architecture. The NetBIOS messages are encapsulated in UDP messages and sent using the IP broadcast address. In effect, IP acts as the broadcast medium for the NetBIOS protocol.

The B-node architecture doesn't address the problem of broadcast dependence, so NBT loads a cache with netBIOS-name-to-IP-address mappings from the LMHOSTS file.

In the B-node model, broadcast are only needed for name resolution. Other messages are addressed directly to the remote host. Therefore, broadcasts are only needed for names that cannot be resolved by other means. NBT also uses a name cache to further improve performance. The name cache provides information about computers that cannot respond to a broadcast. These are computers located outside of the broadcast area, including computers located behind routers or on non-broadcast links. Broadcasts continue to be used to local computers, so no entries need to be made for them in the LMHOSTS file. This keeps the file small and permits it to be cached in memory.

Encapsulating NetBIOS inside IP datagrams reduces the performance and increase the complexity of the protocol. Both protocols requires some level of configuration, whether it is the address for IP or he LMHOSTS file for NetBIOS.

NetBIOS-specific information are the hostname, and are the workgroup name.

Windows Internet Name Service (WINS):

It is a protocol to provide name service for NetBIOS names. The advantage of WINS is that it dynamically learns names and addresses from the transmission on the network, and that it can be dynamically updated by DHCP. The disadvantage is that it requires an NT server, and it is primarily a NetBIOS service. It is generally not used on TCP/IP networks.

DNS Windows Name Resolution:

Can be used to map a NetBIOS name to an IP address, but only if the NetBIOS name and the Internet hostname of the computer are the same. It is a good idea to always make the NetBIOS name and the hostname the same on every system

LMHOSTS File Lookup:

Is a simple flat file that associates NetBIOS names with IP addresses.

#PRE Causes the entry to be pre-loaded into the cache and permanently retained there. Normally entries are only cached when they are used for name resolution and are only retained in the cache for a few minutes. Use #PRE to speed up address resolution for frequently used hostnames.

#DOM Domain identifies NT domain controllers.

#INCLUDE File specifies a remote file that should be incorporated in the local LMHOSTS file. This allows a centrally maintained LMHOSTS file to be automatically loaded. To provide redundant sources for LMHOSTS, enclose a group of #INCLUDE commands inside a pair of #BEGIN_ALTERNATE and #END_ALTERNATE statements. The system tries the various sources in order and stops as soon it successfully downloads one copy of the LMHOSTS file.

9.29.67.1   SERVER01   #PRE
9.29.67.2   SERVER02   #PRE #DOM:DOMAIN01
9.29.67.3   SERVER03
#BEGIN_ALTERNATE
#INCLUDE \\ SERVER01 \ADMIN\lmhosts
#INCLUDE \\ SERVER02\ADMIN\lmhosts
#END_ALTERNATE

The system first checks the LMHOSTS file and then issues a DNS query if the NetBIOS name is not found in the file. Many systems use a small LMHOSTS file to provide the addresses of important servers.

Just a note: IF you decide to edit the LMHOSTS file, rebooting Windows95,98 or NT is NOT required. Simply issue the following commands from a DOS command window:

nbtstat -R
nbtstat -c

You should see something like this:

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