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First set the variable $hexchars:
Change the number in the first for loop if you need less then 1200 mac addresses
It connects to XXX.XXX.XXX.XXX port YYY, using a source port of "srcport" and binds the tunnel on local port "locport". Then you can connect to localhost:locport.
With this command it's possible to connect to servers using a specific source port (useful when a firewall check the source port). Because of the connections starting from the same source port, this works well only for the first connection (for example, works well with SSH and bad with HTTP because of multiple requests).
* It requires socat
This is like ping -a, but it does the opposite. It alerts you if the network is down, not up. Note that the beep will be from the speaker on the server, not from your terminal.
Once a second, this script checks if the Internet is accessible and beeps if it is not. I define the Net as being "UP", if I can ping Google's public DNS server (188.8.131.52), but of course you could pick a different static IP address. I redirect the beep to /dev/console so that I can run this in the background from /etc/rc.local. Of course, doing that requires that the script is run by a UID or GID that has write permissions to /dev/console (usually only root).
Question: I am not sure if the -W1 flag works under BSD. I have only tested this under GNU/Linux using ping from iputils. If anybody knows how portable -W is, please post a comment.
Curl is not installed by default on many common distros anymore. wget always is :)
wget -qO- ifconfig.me/ip
Here's a version that uses netcat (although I'd much rather use curl!).
If curl isn't available, use lynx.
With a lolcat favicon if you access it from your browser
Works on any machine with nmap installed. Previous version does not work on machines without "seq".
Also works on subnets of any size.
Request all information about my IP address in json format
Request all information about my IP address in xml format
Trickle is a voluntary, cooperative bandwidth shaper. it works entirely in userland and is very easy to use.
The most simple application is to limit the bandwidth usage of programs.
Gets only when the state is connected.
Allows to add more than one ip address to one network device.
Shows how many Windows and Linux devices are on your network.
May add support for others, but that's all that are on my network right now.
same thing as the other
Require ips and ipcalc