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Gives the DNS listed IP for the host you're on... or replace `hostname` with any other host
The files are automatically uncompressed when they reach the destination machine. This is a fast way to backup your server to your local computer while it's running (shutting down services is recommended).
A file named "exclude.txt" is needed at /tmp/ containing the following :
connect to it with any network command (including web browser - if you don't mind weird formatting)
nc 127.0.0.1 9876
The sed script ensures that the "random" MAC address is unicast (bit 0 of first byte == 0) and local (bit 1 of first byte == 1)
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 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.
Check trough unix sockets if tcp port is open or close
Gets your IP address and has a shorter URL.
No junk, no pipe, one command, no subcommand - KISS
Why use many different utilities all piped together, when you only need two?
Nethogs groups bandwidth by process.
Requires software found at: http://lpccomp.bc.ca/remserial/
Remote [A] (with physical serial port connected to device)
./remserial -d -p 23000 -s "115200 raw" /dev/ttyS0 &
Local [B] (running the program that needs to connect to serial device)
Create a SSH tunnel to the remote server:
ssh -N -L 23000:localhost:23000 user@hostwithphysicalserialport
Use the locally tunnelled port to connect the local virtual serial port to the remote real physical port:
./remserial -d -r localhost -p 23000 -l /dev/remser1 /dev/ptmx &
Example: Running minicom on machine B using serial /dev/remser1 will actually connect you to whatever device is plugged into machine A's serial port /dev/ttyS0.