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Commands tagged port from sorted by
Terminal - Commands tagged port - 15 results
nc -zv localhost 25
2013-11-21 22:04:00
User: toaster

Using netcat (nc)

25 can be replaced with the friendly value (smtp). Check error code for result or use -v option to echo output

nc -z localhost smtp && echo open || echo closed

nc -zv host protocol

netstat -lntp
sudo lsof -iTCP:25
sudo lsof -iTCP:25 -sTCP:LISTEN
netstat -tln | grep :25
2013-11-12 16:47:06
User: Peteches
Functions: grep netstat

netstat will list all open ports on the system, unix sockets, tcp sockets and udp sockets. the t flag limits to tcp ports the l flag limits to listening ports and the n flag disables the translation of port to service ( ie :25 displayed instead of :smtp ). then grep for the port you are interested in preceeded by a colon.

(echo >/dev/tcp/localhost/25) &>/dev/null && echo "TCP port 25 open" || echo "TCP port 25 close"
2013-11-12 02:11:01
User: YouM
Functions: echo

Check trough unix sockets if tcp port is open or close

sudo port selfupdate && sudo port upgrade outdated && sudo port clean --all installed && sudo port -f uninstall inactive
nc -l <port-number>
2013-03-20 15:25:57
User: cybertoast

Simple way to test if a port is available to the public. Run this command on the "server" and run a `telnet host-ip port-number` on the client. Test by sending strings to the server, which will be displayed in the server terminal.

lsof -nPi tcp:80
fuser -v 80/tcp
checkport() { sudo nmap -sS -p $1 $2 }
2011-12-13 11:46:15
Functions: sudo
Tags: nmap scan port

Check to see if a port is open or closed on a given host.

netstat -tulpnc
2011-04-20 07:30:31
User: altern
Functions: netstat

shows opened ports on machine in continuous mode (refreshing every 10 sec)

nc -z <IP> <TCP port> OR nc -zu <IP> <UDP port>
2011-04-01 04:08:53
User: frank514
Tags: telnet port

-z: Specifies that nc should just scan for listening daemons, without sending any data to them

-u: Use UDP instead of the default option of TCP.

rsync --progress --partial --rsh="ssh -p 8322" --bwlimit=100 --ipv4 user@domain.com:~/file.tgz .
2011-02-10 14:25:22
User: ruslan
Functions: rsync

The command copies a file from remote SSH host on port 8322 with bandwidth limit 100KB/sec;

--progress shows a progress bar

--partial turns partial download on; thus, you can resume the process if something goes wrong

--bwlimit limits bandwidth by specified KB/sec

--ipv4 selects IPv4 as preferred

I find it useful to create the following alias:

alias myscp='rsync --progress --partial --rsh="ssh -p 8322" --bwlimit=100 --ipv4'

in ~/.bash_aliases, ~/.bash_profile, ~/.bash_login or ~/.bashrc where appropriate.

for i in {21..29}; do nc -v -n -z -w 1 192.168.0.$i 443; done
2009-09-25 03:31:29
User: rez0r

Simple one-liner for scanning a range of hosts, you can also scan a range of ports with Netcat by ex.: nc -v -n -z -w 1 21-443

Useful when Nmap is not available:)

Range declaration like X..X "for i in {21..29}" is only works with bash 3.0+