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SS(8)			    System Manager's Manual			 SS(8)

       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  dis-
	      played as follows:

		     1.	 If valid pid show the process context.

		     2.	 If  destination  is kernel (pid = 0) show kernel ini-
			 tial context.

		     3.	 If a unique identifier has been allocated by the ker-
			 nel  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 fami-
	      lies are supported: unix, inet, inet6, link, netlink.

       -A QUERY, --query=QUERY, --socket=QUERY
	      List of socket tables to dump, separated by commas. The  follow-
	      ing  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 inter-
	      preted like single command line option. If FILE is  -  stdin  is

       FILTER := [ state STATE-FILTER ] [ EXPRESSION ]
	      Please  take  a  look  at	 the  official	documentation (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.ps (package iproute-doc),
       RFC 793 - https://tools.ietf.org/rfc/rfc793.txt (TCP states)

       ss was written by Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>.

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