Reverse lookup

dig -x [ip addr]

Query name server for IP addresses

nslookup [name] [dns server]

Get nameserver glue records

# get root servers
dig NS com
# get glue records
dig NS example.com @b.gtld-servers.net

Get SOA (serial, refresh, retry, expiry, minimum)

dig +short example.com soa

Add Route53 subdomain to zone file

; drop this in the example.com zone file
$ORIGIN subdomain.example.com.
@ IN NS ns-x.awsdns-x.net.
@ IN NS ns-x.awsdns-x.com.
@ IN NS ns-x.awsdns-x.co.uk.
@ IN NS ns-x.awsdns-x.org.