There are some URLs which are able to return the public/external IP address of your machines.
- http://checkip.amazonaws.com (Returning an IP address only)
- http://whatismyip.akamai.com (Returning an IP address only)
- http://checkip.dyndns.org (Returning a HTML page)
- http://checkip.dns.he.net (Returning a HTML page)
Get the public/external IP via command line using http services (any one of the followings):
$ curl http://checkip.amazonaws.com
$ curl http://whatismyip.akamai.com
Get the public/external IP via command line using dns services (any one of the followings):
$ dig myip.opendns.com @resolver1.opendns.com +short
$ dig whoami.akamai.net @ns1-1.akamaitech.net +short