|NetBIOS and WINS
|MS provides many options for name resolution such as local cache lookup, WINS server query, broadcast, DNS server query, and LMHOSTS and HOSTS lookup. They can be grouped as two categories: NetBIOS resolution and Host name resolution. Clients connecting to resources on Microsoft servers, typically through Windows File Manager or Network Neighborhood, most often use NetBIOS name resolution. Microsoft TCP/IP uses NetBIOS over TCP/IP (NetBT) to support the NetBIOS client and server programs in the LAN and WAN environments.|
In the most cases, NetBIOS over TCP/IP (NetBT) resolves NetBIOS names to IP addresses in workgroup network and can consist of local subnet broadcasts. WINS resolves NetBIOS names to IP addresses in domain network and is better to be used in WAN.
Host name resolution resolves the names of TCP/IP resources that do not connect through the NetBIOS interface. The most common example of this is a Web browser such as Microsoft Internet Explorer. Other examples include Internet applications such as Ping, FTP, and Telnet. Many modern database and mail applications that connect using Winsock, the Microsoft Windows implementation of TCP/IP sockets, also use host name resolution. Examples of these types of applications are Outlook and Exchange.
If the name is still not resolved, NetBIOS name resolution sequence is used as a backup. This order can be changed by configuring the NetBIOS node type of the client.
In conclusion: The default resolution order for resolving a host name is Local Cached Information -> Hosts File -> DNS Servers -> NetBt (NetBIOS over TCP/IP). When troubleshooting name resolution issues, it is important to narrow down whether the application is resolving a NetBIOS name or a host name.
NetBIOS over TCP/IP name resolution can consist of local subnet broadcasts.
NetBIOS names must be between 1 and 15 characters long (the names are up to 16 characters, but the last character is reserved as a special characters). For that reason, you should not give a computer name longer than 15 characters.
causes: 1. No rights to run
2. Missing NetBT parameters in registry.
3. NetBIOS is not enabled.
If your have non-WINS machines on a subnet and want to them to be visible browsing participants, you may have two options to setup WINS for non-WINS machines. 1) Enable WINS Agent. To setup a machine as proxy agent in NT 4, run regedit and go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NetBT\Parameters. Double-click on the EnableProxy and set vale to 1. 2) add static entries on WINS Manager. To do this, run WINS Manager>Mappings>Static Mappings and add information.
To check if the computer has registered a 00, a 03, and a 20 entry, and these correspond to the Workstation service, the Messenger service, and the Server service, respectively, use nbtstat -n. That will list local NetBIOS names. To list remote computer name table, use nbtstat -a computer name or nbtstat -A IP.
How to disable WINS Proxy
To disable wins proxy, go to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Netbt\Parameters, change the value to 0.
Value Name: EnableProxy
Value Type: REG_DWORD
Values: Boolean (0 or 1)
1. For W2K/XP, go to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Netbt\Parameters
to make change:
Value Type: REG_DWORD - Number
Valid Range: 1,2,4,8 (b-node, p-node, m-node, h-node)
Default: 1 or 8 based on the WINS server configuration
If this key is present, it will override the DhcpNodeType key. If neither key is present, the system defaults to b-node if there are no WINS servers configured for the client. The system defaults to h-node if there is at least one WINS server configured.
If DNS is enabled (which also enabled LMHOSTS in Windows 95), name resolution will also follow the mode defined by this parameter. This value can also be configured using DHCP.
If you can ping a remote computer IP but not the name, and you have WINS or enable NetBIOS over TCP/IP, this may be an outdated NetBIOS name resolution in the local NetBIOS name cache. You may want to run NBTSTAT -r to reset the cache and force the computer to retrieve remote computer name.
Some w2k/xp computer have a difficulty to connect to a laptop and your company has standardized on DNS for name resolution (no WINS and NetBIOS enabled). you also find that you can ping the laptop ip but not name. You may want to run ipconfig /registerdns to renew the ip configuration and register the laptop's DNS name with the DNS.
Before the XP, the name resolution generally occurs in the following order: 1. NetBIOS remote name cache; 2. WINS server; 3. Broadcast; 4. LMHOSTS file; 5. HOSTS; 6. DNS.
If nbtstat -n doesn't show <20> that is server services, make sure 1) the computer starts server service automatically; 2) you have installed File and Printer Sharing; 3) Enable NetBIOS.
NetBIOS and WINS name resolution is required only on mixed-mode (Windows 95, 98, Me, NT, 2000 and XP) networks to provide backward-compatibility older versions of Windows. If you have a domain mixed-mode network with DHCP and DNS, you are better to create WINS in your system. In workgroup mixed-mode network, most people enable NetBIOS over TCP/IP to resolve NetBIOS name to equivalent to IP addresses. Alternatively, you can install NetBEUI protocol in the clients.
After installing/removing a software such as AOL and MS update, the Node Type is modifies. As the result, you may have a connectivity issue. Refer to case 091304XP
Point-to-Point node type relies on WINS servers for NetBIOS name resolution. If the WINS server is unavailable, or if a node isnít configured to contact a WINS server, the computer will not be able to ping other computer by name.
In a mixed OS (win9x, NT, ME, W2K and XP) workgroup network, you may need to enable NetBIOS over TCP/IP on w2k/xp. However, you may be in a situation that enabling netbios over tcp/ip doesn't work, but loading netbeui solve the name resolution problem. There are many reasons for this. One of the popular reasons is some software like firewall and NAT disable or block the TCP/IP. One of solutions is loading NetBEUI on w2k/xp. Note: loading netbeui may be slower the network and netbeui is not routable.
If you can't browse Network Neighborhood/My Network Places, but you can connect to file and print shares by using UNC to map the networking resources, you have a name resolution issue. Your may need to setup WINS server or enable NetBIOS over tcp/ip,
Pro operate as a client on a LAN using netbeui?
A: NetBEUI is unsupported WinXP by default. However, you can install NetBEUI from the XP CD (Re: Q301041).
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