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Get your external IP address if your machine has a DNS entry

Terminal - Get your external IP address if your machine has a DNS entry
host $HOSTNAME|cut -d' ' -f4
2009-08-08 12:39:00
User: penpen
Functions: cut host
Get your external IP address if your machine has a DNS entry

Using DynDNS or a similar service not only allows access to your home machine from outside without needing to know what IP the ISP has assigned to it but it also comes in handy if you want to know your external IP address. The only purpose of the sed command is to remove the leading "host.na.me has address " part from the output. If you don't need to discard it you can simply use



There are 3 alternatives - vote for the best!

Terminal - Alternatives
dig +short $HOSTNAME
curl www.whatismyip.com/automation/n09230945.asp

Know a better way?

If you can do better, submit your command here.

What others think

host $HOSTNAME|head -1 |cut -d' ' -f4

Comment by commandlinefu 321 weeks and 3 days ago

This might not give you what you want, depending on which version of host you have. Different hosts have different output formats. dig +short is defintely the better option, because there's only the ISC version of dig (afaik). The curl alternative does something completely different; it just tells you what your external ip address is, it doesn't resolve your hostname.

Comment by andrew112358 320 weeks and 4 days ago

Your point of view

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