Commands tagged IP

No junk, no pipe, one command, no subcommand - KISS

Why use many different utilities all piped together, when you only need two?

Instead of hard-coding in a check to scrape info from ifconfig based on a specific interface, do it in a more portable way.

This works really well if you switch between wired, wireless, bluetooth or even VPN connections. You can get your current IP in a script (since it'll be something like tun0 instead of eth0 or wlan1).

This uses a well known public ip address 8.8.8.8, but it doesn't actually connect to it, it just shows you the route it would take.

That's the easiest way to do it. -I (or capital i) display all network addresses of a host

gives u each configured IP in a seperate line.

Get the first IPv4 address of an interface

cut -f1,2 - IP range 16

cut -f1,2,3 - IP range 24

cut -f1,2,3,4 - IP range 24

Your IP address is 0.0.0.0

Reciprocally, we could get the node name from a give Tor IP address =>

ip2node() { curl -s -d "QueryIP=$1" http://torstatus.blutmagie.de/tor_exit_query.php | grep -oP "Server name:.*'>\K\w+" ; }

ip2node 204.8.156.142

BostonUCompSci

export THISOS="`uname -s`"

if [ "$THISOS" = "SunOS" ]

then

export THISRELEASE="`uname -r`"

ping1() { ping -s $1 56 1 | egrep "^64"; }

elif [ "$THISOS" = "AIX" ]

then

export THISRELEASE="`uname -v`.`uname -r`"

ping1() { ping -w ${2:-1} $1 56 1 | egrep "^64"; }

elif [ "$THISOS" = "Linux" ]

then

export THISRELEASE="`uname -r`"

ping1() { ping -c 1 -w ${2:-1} $1 | egrep "^64"; }

fi

I have used single packet, and in a silent mode with no display of ping stats. This is with color and UI improvement to the http://www.commandlinefu.com/commands/view/10220/check-if-a-machine-is-online. It is as per the enhancements suggested.

PING

parameters

c 1 limits to 1 pinging attempt

q makes the command quiet (or silent mode)

/dev/null 2>&1 is to remove the display

&& echo ONLINE is executed if previous command is successful (return value 0)

|| echo OFFLINE is executed otherwise (return value of 1 if unreachable or 2 if you're offline yourself).

I personally use this command as an alias with a predefined machine name but there are at least 2 improvements that may be done.

Asking for the machine name or IP

Escaping the output so that it displays ONLINE in green and OFFLINE in red (for instance).

Converts IP octets to hex using printf command. Useful for generating pxeboot aliases in the pxelinux.cfg folder.

Grabs your external public IP.

Provides a cleaner output plus some more details about the IP address. Also, a flaw was corrected where the URL provided the results in Spanish by default.

has the benefit of being a bit more cross-platform.