$ perl -MRegexp::Common=net -wnE '/^$RE{net}{IPv4}/ and next; /^\S+\s+.*?$RE{net}{IPv4}/ and say' 127.0.0.1aaa 127.0.0.1 256.0.0.1aaa 127.0.0.1 256.0.0.1aaa 127.0.0.1 aaa 127.0.0.1 aaa 127.0.0.1