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NETSTAT(8)		   Linux Programmer's Manual		    NETSTAT(8)

NAME
       netstat	- Print network connections, routing tables, interface statis‐
       tics, masquerade connections, and multicast memberships

SYNOPSIS
       netstat	[address_family_options]  [--tcp|-t]   [--udp|-u]   [--raw|-w]
       [--listening|-l]	    [--all|-a]	   [--numeric|-n]    [--numeric-hosts]
       [--numeric-ports]	   [--numeric-users]	       [--symbolic|-N]
       [--extend|-e[--extend|-e]]  [--timers|-o] [--program|-p] [--verbose|-v]
       [--continuous|-c]

       netstat		    {--route|-r}	      [address_family_options]
       [--extend|-e[--extend|-e]]	  [--verbose|-v]	[--numeric|-n]
       [--numeric-hosts] [--numeric-ports] [--numeric-users] [--continuous|-c]

       netstat {--interfaces|-i} [--all|-a] [--extend|-e[--extend|-e]] [--ver‐
       bose|-v]	 [--program|-p]	 [--numeric|-n]	 [--numeric-hosts] [--numeric-
       ports] [--numeric-users] [--continuous|-c]

       netstat	    {--groups|-g}	[--numeric|-n]	     [--numeric-hosts]
       [--numeric-ports] [--numeric-users] [--continuous|-c]

       netstat	     {--masquerade|-M}	     [--extend|-e]	[--numeric|-n]
       [--numeric-hosts] [--numeric-ports] [--numeric-users] [--continuous|-c]

       netstat {--statistics|-s} [--tcp|-t] [--udp|-u] [--raw|-w]

       netstat {--version|-V}

       netstat {--help|-h}

       address_family_options:

       [-4]	 [-6]	    [--protocol={inet,unix,ipx,ax25,netrom,ddp}[,...]]
       [--unix|-x] [--inet|--ip] [--ax25] [--ipx] [--netrom] [--ddp]

DESCRIPTION
       Netstat	prints	information about the Linux networking subsystem.  The
       type of information printed is controlled by  the  first	 argument,  as
       follows:

   (none)
       By  default,  netstat  displays	a  list of open sockets.  If you don't
       specify any address families, then the active sockets of all configured
       address families will be printed.

   --route , -r
       Display	the kernel routing tables. See the description in route(8) for
       details.	 netstat -r and route -e produce the same output.

   --groups , -g
       Display multicast group membership information for IPv4 and IPv6.

   --interfaces, -i
       Display a table of all network interfaces.

   --masquerade , -M
       Display a list of masqueraded connections.

   --statistics , -s
       Display summary statistics for each protocol.

OPTIONS
   --verbose , -v
       Tell the user what is going on by being verbose. Especially print  some
       useful information about unconfigured address families.

   --wide , -W
       Do not truncate IP addresses by using output as wide as needed. This is
       optional for now to not break existing scripts.

   --numeric , -n
       Show numerical addresses instead of trying to determine symbolic	 host,
       port or user names.

   --numeric-hosts
       shows  numerical	 host  addresses but does not affect the resolution of
       port or user names.

   --numeric-ports
       shows numerical port numbers but does not affect the resolution of host
       or user names.

   --numeric-users
       shows  numerical user IDs but does not affect the resolution of host or
       port names.

   --protocol=family , -A
       Specifies the address families (perhaps better described as  low	 level
       protocols)  for	which  connections are to be shown.  family is a comma
       (',') separated list of address family keywords like inet,  unix,  ipx,
       ax25,  netrom,  and ddp.	 This has the same effect as using the --inet,
       --unix (-x), --ipx, --ax25, --netrom, and --ddp options.

       The address family inet includes raw, udp and tcp protocol sockets.

   -c, --continuous
       This will cause netstat to print the selected information every	second
       continuously.

   -e, --extend
       Display	additional  information.   Use	this  option twice for maximum
       detail.

   -o, --timers
       Include information related to networking timers.

   -p, --program
       Show the PID and name of the program to which each socket belongs.

   -l, --listening
       Show only listening sockets.  (These are omitted by default.)

   -a, --all
       Show both listening and non-listening sockets.  With  the  --interfaces
       option, show interfaces that are not up

   -F
       Print routing information from the FIB.	(This is the default.)

   -C
       Print routing information from the route cache.

OUTPUT
   Active Internet connections (TCP, UDP, raw)
   Proto
       The protocol (tcp, udp, raw) used by the socket.

   Recv-Q
       The  count  of  bytes  not copied by the user program connected to this
       socket.

   Send-Q
       The count of bytes not acknowledged by the remote host.

   Local Address
       Address and port number of the local end of  the	 socket.   Unless  the
       --numeric  (-n)	option is specified, the socket address is resolved to
       its canonical host name (FQDN), and the port number is translated  into
       the corresponding service name.

   Foreign Address
       Address	and port number of the remote end of the socket.  Analogous to
       "Local Address."

   State
       The state of the socket. Since there are no states in raw mode and usu‐
       ally  no	 states	 used  in UDP, this column may be left blank. Normally
       this can be one of several values:

       ESTABLISHED
	      The socket has an established connection.

       SYN_SENT
	      The socket is actively attempting to establish a connection.

       SYN_RECV
	      A connection request has been received from the network.

       FIN_WAIT1
	      The socket is closed, and the connection is shutting down.

       FIN_WAIT2
	      Connection is closed, and the socket is waiting for  a  shutdown
	      from the remote end.

       TIME_WAIT
	      The socket is waiting after close to handle packets still in the
	      network.

       CLOSE  The socket is not being used.

       CLOSE_WAIT
	      The remote end has shut down, waiting for the socket to close.

       LAST_ACK
	      The remote end has shut down, and the socket is closed.  Waiting
	      for acknowledgement.

       LISTEN The  socket is listening for incoming connections.  Such sockets
	      are not included in the output unless you specify the  --listen‐
	      ing (-l) or --all (-a) option.

       CLOSING
	      Both  sockets are shut down but we still don't have all our data
	      sent.

       UNKNOWN
	      The state of the socket is unknown.

   User
       The username or the user id (UID) of the owner of the socket.

   PID/Program name
       Slash-separated pair of the process id (PID) and process	 name  of  the
       process	that  owns  the	 socket.   --program  causes this column to be
       included.  You will also need superuser privileges to see this informa‐
       tion  on sockets you don't own.	This identification information is not
       yet available for IPX sockets.

   Timer
       (this needs to be written)

   Active UNIX domain Sockets
   Proto
       The protocol (usually unix) used by the socket.

   RefCnt
       The reference count (i.e. attached processes via this socket).

   Flags
       The flags displayed is SO_ACCEPTON (displayed as ACC), SO_WAITDATA  (W)
       or  SO_NOSPACE  (N).   SO_ACCECPTON  is	used on unconnected sockets if
       their corresponding processes are waiting for a	connect	 request.  The
       other flags are not of normal interest.

   Type
       There are several types of socket access:

       SOCK_DGRAM
	      The socket is used in Datagram (connectionless) mode.

       SOCK_STREAM
	      This is a stream (connection) socket.

       SOCK_RAW
	      The socket is used as a raw socket.

       SOCK_RDM
	      This one serves reliably-delivered messages.

       SOCK_SEQPACKET
	      This is a sequential packet socket.

       SOCK_PACKET
	      Raw interface access socket.

       UNKNOWN
	      Who ever knows what the future will bring us - just fill in here
	      :-)

   State
       This field will contain one of the following Keywords:

       FREE   The socket is not allocated

       LISTENING
	      The socket is listening for a connection request.	 Such  sockets
	      are  only	 included in the output if you specify the --listening
	      (-l) or --all (-a) option.

       CONNECTING
	      The socket is about to establish a connection.

       CONNECTED
	      The socket is connected.

       DISCONNECTING
	      The socket is disconnecting.

       (empty)
	      The socket is not connected to another one.

       UNKNOWN
	      This state should never happen.

   PID/Program name
       Process ID (PID) and process name of the process that  has  the	socket
       open.  More info available in Active Internet connections section writ‐
       ten above.

   Path
       This is the path name as which the corresponding processes attached  to
       the socket.

   Active IPX sockets
       (this needs to be done by somebody who knows it)

   Active NET/ROM sockets
       (this needs to be done by somebody who knows it)

   Active AX.25 sockets
       (this needs to be done by somebody who knows it)

NOTES
       Starting with Linux release 2.2 netstat -i does not show interface sta‐
       tistics for alias interfaces. To get per alias interface	 counters  you
       need to setup explicit rules using the ipchains(8) command.

FILES
       /etc/services -- The services translation file

       /proc  --  Mount	 point	for the proc filesystem, which gives access to
       kernel status information via the following files.

       /proc/net/dev -- device information

       /proc/net/raw -- raw socket information

       /proc/net/tcp -- TCP socket information

       /proc/net/udp -- UDP socket information

       /proc/net/igmp -- IGMP multicast information

       /proc/net/unix -- Unix domain socket information

       /proc/net/ipx -- IPX socket information

       /proc/net/ax25 -- AX25 socket information

       /proc/net/appletalk -- DDP (appletalk) socket information

       /proc/net/nr -- NET/ROM socket information

       /proc/net/route -- IP routing information

       /proc/net/ax25_route -- AX25 routing information

       /proc/net/ipx_route -- IPX routing information

       /proc/net/nr_nodes -- NET/ROM nodelist

       /proc/net/nr_neigh -- NET/ROM neighbours

       /proc/net/ip_masquerade -- masqueraded connections

       /proc/net/snmp -- statistics

SEE ALSO
       route(8), ifconfig(8), ipchains(8), iptables(8), proc(5)

BUGS
       Occasionally strange information may appear if a socket changes	as  it
       is viewed. This is unlikely to occur.

AUTHORS
       The   netstat   user   interface	  was	written	  by  Fred  Baumgarten
       <dc6iq@insu1.etec.uni-karlsruhe.de>, the man  page  basically  by  Matt
       Welsh	<mdw@tc.cornell.edu>.	 It    was   updated   by   Alan   Cox
       <Alan.Cox@linux.org> but could do with a bit more work.	It was updated
       again by Tuan Hoang <tqhoang@bigfoot.com>.
       The  man	 page  and  the	 command  included in the net-tools package is
       totally rewritten by Bernd Eckenfels <ecki@linux.de>.

net-tools			  2008-11-16			    NETSTAT(8)
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