Provided by: nbtscan_1.6-1_amd64 
NAME
nbtscan - scan networks for NetBIOS name information
SYNOPSIS
nbtscan [-v] [-d] [-e] [-l] [-t timeout] [-b bandwidth] [-r] [-q]
[-s separator] [-h] [-m retransmits] [-f filename | target]
DESCRIPTION
NBTscan is a program for scanning IP networks for NetBIOS name information. It sends
NetBIOS status query to each address in supplied range and lists received information in
human readable form. For each responded host it lists IP address, NetBIOS computer name,
logged-in user name and MAC address (such as Ethernet).
NBTscan produces a report like that:
IP address NetBIOS Name Server User MAC address
------------------------------------------------------------------------------
192.168.1.2 MYCOMPUTER JDOE 00-a0-c9-12-34-56
192.168.1.5 WIN98COMP <server> RROE 00-a0-c9-78-90-00
192.168.1.123 DPTSERVER <server> ADMINISTRATOR 08-00-09-12-34-56
First column lists IP address of responded host. Second column is computer name. Third
column indicates if this computer shares or is able to share files or printers. For NT
machine it means that Server Service is running on this computer. For Windows 95 it means
that "I want to be able to give others access to my files" or "I want to be able to allow
others to print on my printer(s)" checkbox is ticked (in Control Panel/Network/File and
Print Sharing). Most often it means that this computer shares files. Third column shows
user name. If no one is logged on from this computer it is same as computer name. Last
column shows adapter MAC address.
If run with -v switch NBTscan lists whole NetBIOS name table for each responded address.
The output looks like that:
NetBIOS Name Table for Host 192.168.1.123:
Name Service Type
----------------------------------------
DPTSERVER <00> UNIQUE
DPTSERVER <20> UNIQUE
DEPARTMENT <00> GROUP
DEPARTMENT <1c> GROUP
DEPARTMENT <1b> UNIQUE
DEPARTMENT <1e> GROUP
DPTSERVER <03> UNIQUE
DEPARTMENT <1d> UNIQUE
??__MSBROWSE__? <01> GROUP
INet~Services <1c> GROUP
IS~DPTSERVER <00> UNIQUE
DPTSERVER <01> UNIQUE
Adapter address: 00-a0-c9-12-34-56
----------------------------------------
OPTIONS
A summary of options is included below.
-v Verbose output. Print all names received from each host.
-d Dump packets. Print whole packet contents. Cannot be used with -v, -s or -h
options.
-e Format output in /etc/hosts format.
-l Format output in lmhosts format.
-t <timeout>
Wait timeout seconds for response. Default 1.
-b <bandwidth>
Output throttling. Slow down output so that it uses no more that bandwidth bps.
Useful on slow links, so that outgoing queries don't get dropped.
-r Use local port 137 for scans. Win95 boxes respond to this only. You need to be root
to use this option.
-q Suppress banners and error messages.
-s <separator>
Script-friendly output. Don't print column and record headers, separate fields with
separator.
-h Print human-readable names for services. Can only be used with -v option.
-m <retransmits>
Number of retransmits. Default 0.
-f <filename>
Take IP addresses to scan from file "filename"
target NBTscan is a command-line tool. You have to supply at least one argument, the
address range, in one of three forms:
xxx.xxx.xxx.xxx
Single IP in dotted-decimal notation. Example: 192.168.1.1
xxx.xxx.xxx.xxx/xx
Net address and subnet mask. Example: 192.168.1.0/24
xxx.xxx.xxx.xxx-xxx
Address range. Example: 192.168.1.1-127. This will scan all addresses from
192.168.1.1 to 192.168.1.127
EXAMPLES
Scans the whole C-class network:
nbtscan -r 192.168.1.0/24
Scans a range from 192.168.1.25 to 192.168.1.137:
nbtscan 192.168.1.25-137
Scans C-class network. Prints results in script-friendly format using colon as field
separator:
nbtscan -v -s : 192.168.1.0/24
The last command produces output like that:
192.168.0.1:NT_SERVER:00U
192.168.0.1:MY_DOMAIN:00G
192.168.0.1:ADMINISTRATOR:03U
192.168.0.2:OTHER_BOX:00U
...
Scans IP addresses specified in file iplist:
nbtscan -f iplist
NETBIOS SUFFIXES
NetBIOS Suffix, aka NetBIOS End Character (endchar), indicates service type for the
registered name. The most known codes are listed below. (U = Unique Name, G = Group Name)
Name Number(h) Type Usage
--------------------------------------------------------------------------
<computername> 00 U Workstation Service
<computername> 01 U Messenger Service
<\--__MSBROWSE__> 01 G Master Browser
<computername> 03 U Messenger Service
<computername> 06 U RAS Server Service
<computername> 1F U NetDDE Service
<computername> 20 U File Server Service
<computername> 21 U RAS Client Service
<computername> 22 U Exchange Interchange(MSMail Connector)
<computername> 23 U Exchange Store
<computername> 24 U Exchange Directory
<computername> 30 U Modem Sharing Server Service
<computername> 31 U Modem Sharing Client Service
<computername> 43 U SMS Clients Remote Control
<computername> 44 U SMS Administrators Remote Control Tool
<computername> 45 U SMS Clients Remote Chat
<computername> 46 U SMS Clients Remote Transfer
<computername> 87 U Microsoft Exchange MTA
<computername> 6A U Microsoft Exchange IMC
<computername> BE U Network Monitor Agent
<computername> BF U Network Monitor Application
<username> 03 U Messenger Service
<domain> 00 G Domain Name
<domain> 1B U Domain Master Browser
<domain> 1C G Domain Controllers
<domain> 1D U Master Browser
<domain> 1E G Browser Service Elections
<INet~Services> 1C G IIS
<IS~computer name> 00 U IIS
FAQ
1. NBTscan lists my Windows boxes just fine but does not list my Unixes or routers. Why?
R: That is the way it is supposed to work. NBTscan uses NetBIOS for scanning and NetBIOS
is only implemented by Windows (and some software on Unix such as Samba).
2. Why do I get "Connection reset by peer" errors on Windows 2000?
R: NBTscan uses port 137 UDP for sending queries. If the port is closed on destination
host destination will reply with ICMP "Port unreachable" message. Most operating system
will ignore this message. Windows 2000 reports it to the application as "Connection reset
by peer" error. Just ignore it.
3. Why NBTscan doesn't scan for shares? Are you going to add share scanning to NBTscan?
R: No. NBTscan uses UDP for what it does. That makes it very fast. Share scanning requires
TCP. For one thing, it will make nbtscan more slow. Also adding share scanning means
adding a lot of new code to nbtscan. There is a lot of good share scanners around, so
there is no reason to duplicate that work.
4. Why do I get 00-00-00-00-00-00 instead of MAC address when I scan a Samba box?
R: Because that's what Samba send in response to the query. Nbtscan just prints out what
it gets.
AUTHOR
NBTscan was created by Alla Bezroutchko <alla@inetcat.org>. Currently is maintained by
some volunteers at https://github.com/resurrecting-open-source-projects/nbtscan
This manual page was written for the first time by Ryszard Lach <rla@debian.org> and
rewritten, from scratch, by Joao Eriberto Mota Filho <eriberto@debian.org> for the Debian
GNU/Linux system (but may be used by others).