NETSTAT(TC)                                UNIX System V



     Name
          netstat - Show network status


     Syntax
          netstat [ -AainrsS ] [ -f address_family ] [ -I interface  ]
          [ -p protocol_name ] [ interval ] [ namelist ] [ corefile ]


     Description
          The netstat command symbolically displays  the  contents  of
          various  network-related  data structures.  The options have
          the following meanings:

          -A   show the address of  any  associated  protocol  control
               blocks; used for debugging

          -a   show the state of all sockets; normally sockets used by
               server processes are not shown

          -i   show the state  of  interfaces  that  have  been  auto-
               configured.   (Interfaces  statically configured into a
               system, but not located at boot time, are not shown.)

          -n   show network addresses as numbers.   (Normally  netstat
               interprets  addresses  and  attempts  to  display  them
               symbolically.)

          -r   show the routing tables

          -s   show per-protocol statistics

          -S   show serial line configuration

          -f   limit  statistics  and  control   block   displays   to
               address-family.    The  only  address-family  currently
               supported is inet

          -I   show interface state for interface only.

          -p   limit  statistics  and  control   block   displays   to
               protocol_name, such as tcp.

          The arguments namelist and corefile  allow  substitutes  for
          the defaults /unix and /dev/kmem.

          If an  interval  is  specified,  netstat  will  continuously
          display  the  information  regarding  packet  traffic on the
          configured  network  interfaces,  pausing  interval  seconds
          before refreshing the screen.

          There are a number of  display  formats,  depending  on  the
          information  presented.   The  default  display,  for active
          sockets, shows the local  and  remote  addresses,  send  and
          receive  queue  sizes (in bytes), protocol, and, optionally,
          the internal state of the protocol.

          Address formats are of the form host.port or network.port if
          a  socket's address specifies a network but no specific host
          address.  When known, the host  and  network  addresses  are
          displayed   symbolically   according   to   the  data  bases
          /etc/hosts and /etc/networks, respectively.  If  a  symbolic
          name  for  an  address  is  unknown,  or if the -n option is
          specified, the  address  is  printed  in  the  Internet  dot
          format;  refer to rhosts(SFF) for more information regarding
          this format.  Unspecified, or wildcard, addresses and  ports
          appear as *.

          The  interface  display  provides  a  table  of   cumulative
          statistics   regarding   transferred  packets,  errors,  and
          collisions.   The  network   address   (currently   Internet
          specific) of the interface and the maximum transmission unit
          (mtu) are also displayed.

          The routing table display indicates the available routes and
          their  status.  Each route consists of a destination host or
          network and a gateway to use  in  forwarding  packets.   The
          flags  field  shows  the  state  of the route (U if up), and
          whether the route is to a gateway (G).   Direct  routes  are
          created  for each interface attached to the local host.  The
          refcnt field gives the current number of active uses of  the
          route.   Connection-oriented  protocols normally hold onto a
          single  route  for  the  duration  of  a  connection,  while
          connectionless  protocols  obtain  a  route then discard it.
          The use field provides a count of the number of packets sent
          using that route.  The interface entry indicates the network
          interface utilized for the route.

          When netstat  is  invoked  with  an  interval  argument,  it
          displays  a  running  count of statistics related to network
          interfaces.  This display consists of a  column  summarizing
          information   for  all  interfaces  and  a  column  for  the
          interface with the most traffic since the  system  was  last
          rebooted.   The  first  line  of  each screen of information
          contains a summary  since  the  system  was  last  rebooted.
          Subsequent  lines of output show values accumulated over the
          preceding interval.

          The serial line display shows the  mapping  of  serial  line
          units to serial devices.  The baud rate and protocols in use
          are also shown.


     See Also
          slattach(ADMN), hosts(ADMN), networks(SSC),  protocols(SFF),
          services(SFF).


     Bugs
          Interface statistics are dependent on the link driver. If it
          does  not  attach  itself  to  the  ifstats structure in the
          kernel, the message  ``No  Statistics  Available''  will  be
          printed for that interface.


     (printed 8/17/89)                                  NETSTAT(TC)