Dig ip blocks
./netblocks.sh [-d <domain>] | [-i <ip>] | [-g -i <ip>] | -a <asn>
-d : Search by domain
-i : Search by ip
-a : Search by as number
-g : To use with -i to geolocate the ip
-h : This help
whois
linux command with radb.net RIR database