Server Fault Stack Exchange
Server Fault Stack Exchange

Questions tagged [netcat]

Netcat is a featured networking utility which reads and writes data across network connections, using the TCP/IP protocol.

features:

  • Outbound and inbound connections, TCP or UDP, to or from any ports.
  • Featured tunneling mode which allows also special tunneling such as UDP to TCP, with the possibility of specifying all network parameters (source port/interface, listening port/interface, and the remote host allowed to connect to the tunnel.
  • Built-in port-scanning capabilities, with randomizer.
  • Advanced usage options, such as buffered send-mode (one line every N seconds), and hexdump (to stderr or to a specified file) of trasmitted and received data.
  • Optional RFC854 telnet codes parser and responder.
186 questions
0
votes
1 answer

How to check the udp port is accessible in an Ubuntu machine which is protected by a firewall

We were trying to install "Big blue button" in an Ubuntu server with a firewall. For installation, we need these UDP ports ("16384-32768") should be opened in the firewall. But we don't know whether the udp ports are opened or not in the firewall.…
aks
  • 57
  • 2
  • 7
-1
votes
1 answer

netcat, reopen TCP socket

I have a bash script: #!/bin/bash while : do nc -l -p 30003 | python3 script.py done I want that listening works all time. nc localhost 30003 # works, fine *type something* Ctrl+C Try again nc localhost 30003 # not working So,…
user7365441
  • 3
  • 1
-1
votes
1 answer

Can't connect to socket from outside

I have a problem on my server when I start an application that listen to a port: I can connect to it from the same machine, but not from the ouside world. I noticed this problem when trying to create an irc bouncer with irssiproxy (I successfully…
user348222
  • 1
  • 2
-1
votes
1 answer

Sending mail using netcat - getaddrinfo: Name or service not known

i am trying to send a mail using netcat, and i am getting an error: nc: getaddrinfo: Name or service not known this is the command i am using /usr/bin/nc smtp.xxxxx.yy 25 < test.txt this is the content of test.txt xxx.yyy.zz MAIL…
Froggiz
  • 3,043
  • 1
  • 19
  • 30
-2
votes
2 answers

No nc arguments being recognized

I'm having trouble using my nc command. Everytime I enter any parameter, even using -h, linux just prints: *BusyBox v1.20.2 (2014-05-14 13:19:21 EDT) multi-call binary. Usage: nc [IPADDR PORT]* I am able to type nc localhost 22 which produces…
sphchow
  • 101
  • 5
-3
votes
1 answer

Why I can only send 3 row via netcat on UDP port?

I am new to this command I am sending a file data on UDP 9415 port . --> I have file which has 1000 rows --> I am firing here IP is my destination IP cat test1 | netcat -u 172.x.x.x 9514 --> Now on destination i have syslog-ng which recieves data…
user3332404
  • 411
  • 1
  • 4
  • 7
1 2 3
…
12
13