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nbtscan(1)	 scan networks searching for NetBIOS information      nbtscan(1)

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 ad-
     dress (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  re-
     sponded 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, sepa-
	    rate 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  ar-
	    gument, 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 192.168.1.0/24

     Scans the whole C-class network, using port 137:

	 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  scan-
     ning  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" mes-
     sage. 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 scan-
	 ning 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@de-
     bian.org> and rewritten, from scratch, by Joao Eriberto Mota  Filho  <erib-
     erto@debian.org>  for  the Debian GNU/Linux system (but may be used by oth-
     ers).

nbtscan-1.7.2			   13 Jan 2022			      nbtscan(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=nbtscan&sektion=1&manpath=FreeBSD+Ports+15.1.quarterly>

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