ss - another utility to investigate sockets


   ss [options] [ FILTER ]


   ss  is  used  to  dump socket statistics. It allows showing information
   similar to netstat.  It can display more  TCP  and  state  informations
   than other tools.


   When no option is used ss displays a list of open non-listening sockets
   (e.g. TCP/UNIX/UDP) that have established connection.

   -h, --help
          Show summary of options.

   -V, --version
          Output version information.

   -n, --numeric
          Do not try to resolve service names.

   -r, --resolve
          Try to resolve numeric address/ports.

   -a, --all
          Display both listening and non-listening  (for  TCP  this  means
          established connections) sockets.

   -l, --listening
          Display only listening sockets (these are omitted by default).

   -o, --options
          Show timer information.

   -e, --extended
          Show detailed socket information

   -m, --memory
          Show socket memory usage.

   -p, --processes
          Show process using socket.

   -i, --info
          Show internal TCP information.

   -s, --summary
          Print  summary  statistics.  This  option  does not parse socket
          lists obtaining summary from various sources. It is useful  when
          amount  of  sockets  is  so  huge  that parsing /proc/net/tcp is

   -Z, --context
          As the -p option but also shows process security context.

          For  netlink(7)  sockets  the  initiating  process  context   is
          displayed as follows:

                 1.  If valid pid show the process context.

                 2.  If  destination  is  kernel  (pid  =  0)  show kernel
                     initial context.

                 3.  If a unique identifier  has  been  allocated  by  the
                     kernel    or    netlink   user,   show   context   as
                     "unavailable". This will generally  indicate  that  a
                     process has more than one netlink socket active.

   -z, --contexts
          As  the  -Z option but also shows the socket context. The socket
          context is taken from the associated inode and is not the actual
          socket context held by the kernel. Sockets are typically labeled
          with the context of the creating process,  however  the  context
          shown will reflect any policy role, type and/or range transition
          rules applied, and is therefore a useful reference.

   -N NSNAME, --net=NSNAME
          Switch to the specified network namespace name.

   -b, --bpf
          Show socket BPF filters (only administrators are allowed to  get
          these information).

   -4, --ipv4
          Display only IP version 4 sockets (alias for -f inet).

   -6, --ipv6
          Display only IP version 6 sockets (alias for -f inet6).

   -0, --packet
          Display PACKET sockets (alias for -f link).

   -t, --tcp
          Display TCP sockets.

   -u, --udp
          Display UDP sockets.

   -d, --dccp
          Display DCCP sockets.

   -w, --raw
          Display RAW sockets.

   -x, --unix
          Display Unix domain sockets (alias for -f unix).

   -f FAMILY, --family=FAMILY
          Display   sockets  of  type  FAMILY.   Currently  the  following
          families are supported: unix, inet, inet6, link, netlink.

   -A QUERY, --query=QUERY, --socket=QUERY
          List  of  socket  tables  to  dump,  separated  by  commas.  The
          following  identifiers are understood: all, inet, tcp, udp, raw,
          unix, packet, netlink, unix_dgram, unix_stream,  unix_seqpacket,
          packet_raw, packet_dgram.

   -D FILE, --diag=FILE
          Do  not  display  anything,  just dump raw information about TCP
          sockets to FILE after applying filters. If FILE is -  stdout  is

   -F FILE, --filter=FILE
          Read  filter  information  from  FILE.   Each  line  of  FILE is
          interpreted like single command line option. If FILE is -  stdin
          is used.

          Please take a look at the official documentation (Debian package
          iproute-doc) for details regarding filters.


   STATE-FILTER allows to construct arbitrary set of states to match.  Its
   syntax is sequence of keywords state and exclude followed by identifier
   of state.

   Available identifiers are:

          All standard TCP states: established, syn-sent,  syn-recv,  fin-
          wait-1,  fin-wait-2,  time-wait,  closed,  close-wait, last-ack,
          listen and closing.

          all - for all the states

          connected - all the states except for listen and closed

          synchronized - all the connected states except for syn-sent

          bucket - states,  which  are  maintained  as  minisockets,  i.e.
          time-wait and syn-recv

          big - opposite to bucket


   ss -t -a
          Display all TCP sockets.

   ss -t -a -Z
          Display all TCP sockets with process SELinux security contexts.

   ss -u -a
          Display all UDP sockets.

   ss -o state established '( dport = :ssh or sport = :ssh )'
          Display all established ssh connections.

   ss -x src /tmp/.X11-unix/*
          Find all local processes connected to X server.

   ss  -o  state  fin-wait-1  '(  sport  =  :http or sport = :https )' dst
          List all the tcp sockets in state FIN-WAIT-1 for our  apache  to
          network 193.233.7/24 and look at their timers.


   ip(8), /usr/share/doc/iproute-doc/ss.html (package iproutedoc),
   RFC 793 - (TCP states)


   ss was written by Alexey Kuznetsov, <>.

   This  manual page was written by Michael Prokop <> for the
   Debian project (but may be used by others).



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