SS(8) System Manager's Manual SS(8) (NAME) ss - (SYNOPSIS) ss [options] [ FILTER ] (DESCRIPTION) ss . netstat TCP . (OPTIONS) ss ( TCP/UNIX/UDP) . -h, --help . -V, --version . -H, --no-header . -Q, --no-queues . -O, --oneline . -n, --numeric . . -r, --resolve / . -a, --all ( TCP ). -l, --listening ( ). -B, --bound-inactive TCP (bound) ( listening connecting ). -o, --options (). TCP : timer:(,,) : on : : TCP (retrans) TCP tail loss probe keepalive: TCP (keep alive) timewait: timewait persist: (zero window probe) unknown: (retransmission) -e, --extended . : uid: ino: sk: (UID) inode (VFS) UUID -m, --memory . : skmem:(r,rb,t,tb, f,w,o, bl,d) ( ) () . / . ( ) TCP MD5 (backlog) . (de-multiplex) -p, --processes . -T, --threads (thread) . -p . -i, --info TCP. : ts "ts" (timestamp) sack "sack" (sack) ecn "ecn" (ECN) ecnseen "ecnseen" ecn fastopen "fastopen" fastopen cong_alg "cubic" wscale:: rto: TCP (: ) backoff: (exponential backoff) icsk_rto << icsk_backoff rtt:/ rtt rttvar rtt (: ) ato: (ack timeout) (delay ack) mss: (MSS) cwnd: (cwnd) pmtu: MTU (PMTU) ssthresh: TCP bytes_acked: (ACK ) bytes_received: segs_out: segs_in: send bps (egress bps) lastsnd: (: ) lastrcv: (: ) lastack: ACK (: ) pacing_rate bps/bps (pacing rate) rcv_space: TCP tcp-ulp-mptcp flags:[MmBbJjecv] token: seq: sfseq: ssnoff: maplen: MPTCP --tos ToS . : tos (Type-of-Service) IPv4 tclass (Traffic Class) IPv6 class_id net_cls cgroup. SO_PRIORITY . --cgroup cgroup. : cgroup Cgroup v2. . --tipcinfo TIPC. -K, --kill . . IPv4 IPv6 . -s, --summary . . /proc/net/tcp . -E, --events . -Z, --context -p . -T (thread) . netlink(7) : 1. PID . 2. (PID = 0) . 3. netlink "unavailable" . netlink . -z, --contexts -Z . inode . / . -N NSNAME, --net=NSNAME (network namespace) . -b, --bpf BPF ( ). -4, --ipv4 IP ( -f inet). -6, --ipv6 IP ( -f inet6). -0, --packet PACKET ( -f link). -t, --tcp TCP. -u, --udp UDP. -d, --dccp DCCP. -w, --raw RAW. -x, --unix (Unix domain) ( -f unix). -S, --sctp SCTP. --tipc TIPC ( -f tipc). --vsock vsock ( -f vsock). --xdp XDP ( -f xdp). -M, --mptcp MPTCP. --inet-sockopt inet (inet socket options). -f FAMILY, --family=FAMILY FAMILY. : unix, inet, inet6, link, netlink, vsock, tipc, xdp. -A QUERY, --query=QUERY, --socket=QUERY . : all, inet, tcp, udp, raw, unix, packet, netlink, unix_dgram, unix_stream, unix_seqpacket, packet_raw, packet_dgram, dccp, sctp, tipc, vsock_stream, vsock_dgram, xdp, mptcp. (!) . -D FILE, --diag=FILE TCP FILE . FILE - (stdout) . -F FILE, --filter=FILE FILE. FILE . FILE - (stdin) . --bpf-maps BPF . --bpf-map-id=MAP_ID BPF (MAP_ID) . . FILTER := [ state STATE-FILTER ] [ EXPRESSION ] . (STATE-FILTER) STATE-FILTER . (syntax) state exclude . : TCP: established, syn-sent, syn-recv, fin-wait-1, fin-wait-2, time-wait, closed, close-wait, last-ack, listening closing. all - connected - listening closed synchronized - connected syn-sent bucket - time-wait syn-recv big - bucket bound-inactive - (bound) ( listening connecting ) (EXPRESSION) EXPRESSION . EXPRESSION . : or ( | ||) and ( & &&) not ( !). and . "(" ")" . : {dst|src} [=] HOST HOST . (HOST SYNTAX) . {dport|sport} [OP] [FAMILY:]:PORT PORT . OP "<" "<=" "=" "!=" ">=" ">" . FAMILY PORT (HOST SYNTAX) . dev [=|!=] DEVICE . DEVICE (index) . fwmark [=|!=] MASK fwmark . "/" "fwmark = 0x01/0x03" fwmark 0x01 . cgroup [=|!=] PATH cgroup . autobound ( ) . . "=" . : o = == eq o != ne neq o > gt o < lt o >= ge geq o <= le leq o ! not o | || or o & && and (HOST SYNTAX) [FAMILY:]ADDRESS[:PORT] . FAMILY -f . -f inet inet6 . inet inet6 . . ADDRESS PORT . "*" (wildcard) . : unix ADDRESS glob ( fnmatch(3) ) . (abstract) . "*" . link ADDRESS . PORT ip link . netlink ADDRESS netlink . /etc/iproute2/nl_protos . PORT (PID) . "kernel" ( ) . vsock ADDRESS CID PORT . inet and inet6 ADDRESS IP ( v4 v6) DNS IP . IPv6 "[" "]" . CIDR ( ) . PORT . (EXAMPLES) ss -t -a TCP. ss -t -a -Z TCP SELinux . ss -u -a UDP. ss -o state established '( dport = :ssh or sport = :ssh )' SSH. ss -x src /tmp/.X11-unix/* X. ss -o state fin-wait-1 '( sport = :http or sport = :https )' dst 193.233.7/24 TCP FIN-WAIT-1 193.233.7/24 . ss -a -A 'all,!tcp' TCP. (SEE ALSO) ip(8), RFC 793 - https://tools.ietf.org/rfc/rfc793.txt ( TCP) (AUTHOR) ss Alexey Kuznetsov . Michael Prokop ( ). SS(8)