github.com/pmoroney/dnscontrol@v0.2.4-0.20171024134423-fad98f73f44a/integrationTest/zones/example.com.zone (about)

     1  $TTL 300
     2  @                IN SOA   DEFAULT_NOT_SET. DEFAULT_NOT_SET. 2017091830 3600 600 604800 1440
     3                   IN NS    ns1.otherdomain.tld.
     4                   IN NS    ns2.otherdomain.tld.