ss
Display socket statistics and connections
TLDR
Show all TCP/UDP/RAW/UNIX sockets
$ ss -a -t
Show all listening sockets$ ss -l
Show all TCP sockets with process information$ ss -tp
Show all TCP sockets connected to local HTTPS port$ ss -t src :443
Show all TCP sockets listening on port 8080$ ss -lt src :8080
Show established SSH connections$ ss -o state established '( dport = :ssh or sport = :ssh )'
Kill a socket connection$ ss -K dst 192.168.1.1 dport = 22
Print summary statistics$ ss -s
SYNOPSIS
ss [options] [FILTER]
DESCRIPTION
ss is used to dump socket statistics. It displays information similar to netstat but can show more TCP and state information than other tools. It retrieves socket information directly from kernel space, making it faster than netstat.
PARAMETERS
-h, --help
Show summary of options-a, --all
Display both listening and non-listening sockets-l, --listening
Display only listening sockets-n, --numeric
Do not resolve service names; show numeric ports-r, --resolve
Attempt to resolve numeric address/ports-p, --processes
Show process using socket-t, --tcp
Display TCP sockets-u, --udp
Display UDP sockets-x, --unix
Display Unix domain sockets-w, --raw
Display raw sockets-4, --ipv4
Display IPv4 sockets only-6, --ipv6
Display IPv6 sockets only-o, --options
Show timer information-e, --extended
Show detailed socket information (UID, inode, cookie)-m, --memory
Show socket memory usage-i, --info
Show internal TCP information-K, --kill
Forcibly close sockets-s, --summary
Print summary statistics-E, --events
Continually display sockets as they are destroyed-N, --net=NSNAME
Switch to specified network namespace
INSTALL
sudo apt install iproute2
sudo pacman -S iproute2
sudo apk add iproute2-ss
sudo zypper install iproute2
brew install iproute2
nix profile install nixpkgs#iproute2
CAVEATS
State filtering supports TCP states (established, syn-sent, syn-recv, fin-wait-1, fin-wait-2, time-wait, closed, close-wait, last-ack, listening, closing) and meta-states (all, connected, synchronized, bucket). The -K option requires appropriate privileges.
HISTORY
ss is part of the iproute2 package and was developed as a modern replacement for netstat. It provides faster performance by reading directly from kernel netlink sockets rather than parsing /proc files.
