SS(category3-sendmail.html) - phpMan

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

NAME
       ss - another utility to investigate sockets
SYNOPSIS
       ss [options] [ FILTER ]
DESCRIPTION
       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.

OPTIONS
       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.
       -H, --no-header
              Suppress header line.
       -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.
       -K, --kill
              Attempts to forcibly close sockets. This option displays sockets
              that are successfully closed and silently skips sockets that the
              kernel does not support closing. It supports IPv4 and IPv6 sock-
              ets only.
       -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
              painful.
       -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).
       -S, --sctp
              Display SCTP sockets.
       --vsock
              Display vsock sockets (alias for -f vsock).
       -f FAMILY, --family=FAMILY
              Display sockets of type FAMILY.  Currently the  following  fami-
              lies are supported: unix, inet, inet6, link, netlink, vsock.
       -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, dccp, sctp, vsock_stream, vsock_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
              used.
       -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
              used.
       FILTER := [ state STATE-FILTER ] [ EXPRESSION ]
              Please take a look at the official documentation (Debian package
              iproute-doc) for details regarding filters.

STATE-FILTER
       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

USAGE EXAMPLES
       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
       193.233.7/24
              List  all  the tcp sockets in state FIN-WAIT-1 for our apache to
              network 193.233.7/24 and look at their timers.
SEE ALSO
       ip(8), /usr/share/doc/iproute-doc/ss.html (package iproutedoc),
       RFC 793 - https://tools.ietf.org/rfc/rfc793.txt (TCP states)

AUTHOR
       ss was written by Alexey Kuznetsov, <kuznet AT ms2.ru>.
       This manual page was written by Michael Prokop <mika AT grml.org> for  the
       Debian project (but may be used by others).

                                                                         SS(8)