Provided by: net-tools_1.60+git20181103.0eebece-1ubuntu5_amd64 bug

NAME

       netstat  -  Print  network  connections,  routing tables, interface statistics, masquerade
       connections, and multicast memberships

SYNOPSIS

       netstat  [address_family_options]   [--tcp|-t]   [--udp|-u]   [--udplite|-U]   [--sctp|-S]
       [--raw|-w]   [--l2cap|-2]   [--rfcomm|-f]   [--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]
       [--wide|-W]

       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]]    [--verbose|-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] [--udplite|-U] [--sctp|-S] [--raw|-w]

       netstat {--version|-V}

       netstat {--help|-h}

       address_family_options:

       [-4|--inet] [-6|--inet6] [--protocol={inet,inet6,unix,ipx,ax25,netrom,ddp,bluetooth, ... }
       ]  [--unix|-x]  [--inet|--ip|--tcpip]  [--ax25]  [--x25]  [--rose]  [--ash]  [--bluetooth]
       [--ipx] [--netrom] [--ddp|--appletalk] [--econet|--ec]

NOTES

       This  program is mostly obsolete.  Replacement for netstat is ss.  Replacement for netstat
       -r is ip route.  Replacement for netstat -i is ip -s link.  Replacement for netstat -g  is
       ip maddr.

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, inet6, unix, ipx, ax25, netrom, econet, ddp, and bluetooth.  This  has
       the  same  effect  as using the --inet|-4, --inet6|-6, --unix|-x, --ipx, --ax25, --netrom,
       --ddp, and --bluetooth options.

       The address family inet (Iv4) includes raw, udp, udplite and tcp protocol sockets.

       The address family bluetooth (Iv4) includes l2cap and rfcomm 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, UDPLite, raw)
   Proto
       The protocol (tcp, udp, udpl, raw) used by the socket.

   Recv-Q
       Established:  The  count of bytes not copied by the user program connected to this socket.
       Listening: Since Kernel 2.6.18 this column contains the current syn backlog.

   Send-Q
       Established: The count of bytes not acknowledged by the  remote  host.   Listening:  Since
       Kernel 2.6.18 this column contains the maximum size of the syn backlog.

   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 usually no states used
       in UDP and UDPLite, 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 --listening (-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  information  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 written 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)

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/udplite -- UDPLite 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

       /sys/kernel/debug/bluetooth/l2cap -- Bluetooth L2CAP information

       /sys/kernel/debug/bluetooth/rfcomm -- Bluetooth serial connections

       /proc/net/snmp -- statistics

SEE ALSO

       route(8), ifconfig(8), iptables(8), proc(5) ss(8) ip(8)

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>,  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>.   UDPLite  options  were
       added by Brian Micek <bmicek@gmail.com>