ref: 5fe33fb80804cadc3c934337fde81af5b7d44243
dir: /sys/lib/dist/ndb/mkfile/
dnsroot:V: hget https://www.internic.net/domain/root.zone | awk ' BEGIN { print "# this file is autogenerated from /sys/lib/dist/ndb/mkfile" }; match($1, "\\.root-servers\\.net\\.") != 0 && \ ($4 == "A" || $4 == "AAAA") { dom = toupper($1); sub("\\.$", "", dom); printf("dom=%s ip=%s\n", dom, $5); }' > $target