--- layout: default title: Examples --- # Examples * TOC {:toc} ## Typical DNS Records ```js D('example.com', REG, DnsProvider('GCLOUD'), A('@', '1.2.3.4'), // The naked or 'apex' domain. A('server1', '2.3.4.5'), AAAA('wide', '2001:0db8:85a3:0000:0000:8a2e:0370:7334'), CNAME('www', 'server1'), CNAME('another', 'service.mycloud.com.'), MX('mail', 10, 'mailserver'), MX('mail', 20, 'mailqueue'), TXT('the', 'message'), NS('department2', 'ns1.dnsexample.com.'), // use different nameservers NS('department2', 'ns2.dnsexample.com.') // for department2.example.com ) ``` ## Set TTLs ```js var mailTTL = TTL('1h'); D('example.com', registrar, NAMESERVER_TTL('10m'), // On domain apex NS RRs DefaultTTL('5m'), // Default for a domain MX('@', 5, '1.2.3.4', mailTTL), // use variable to MX('@', 10, '4.3.2.1', mailTTL), // set TTL A('@', '1.2.3.4', TTL('10m')), // individual record CNAME('mail', 'mx01') // TTL of 5m, as defined per DefaultTTL() ); ``` ## Variables for common IP Addresses ```js var addrA = IP('1.2.3.4') D('example.com', REG, DnsProvider('R53'), A('@', addrA), // 1.2.3.4 A('www', addrA + 1), // 1.2.3.5 ) ``` ## Variables to swap active Data Center ```js var dcA = IP('5.5.5.5'); var dcB = IP('6.6.6.6'); // switch to dcB to failover var activeDC = dcA; D('example.com', REG, DnsProvider('R53'), A('@', activeDC + 5), // fixed address based on activeDC ) ``` ## Macro to for repeated records ```js var GOOGLE_APPS_RECORDS = [ MX('@', 1, 'aspmx.l.google.com.'), MX('@', 5, 'alt1.aspmx.l.google.com.'), MX('@', 5, 'alt2.aspmx.l.google.com.'), MX('@', 10, 'alt3.aspmx.l.google.com.'), MX('@', 10, 'alt4.aspmx.l.google.com.'), CNAME('calendar', 'ghs.googlehosted.com.'), CNAME('drive', 'ghs.googlehosted.com.'), CNAME('mail', 'ghs.googlehosted.com.'), CNAME('groups', 'ghs.googlehosted.com.'), CNAME('sites', 'ghs.googlehosted.com.'), CNAME('start', 'ghs.googlehosted.com.'), ] D('example.com', REG, DnsProvider('R53'), GOOGLE_APPS_RECORDS, A('@', '1.2.3.4') ) ``` ## Add comments along complex SPF records You normally can't put comments in the middle of a string, but with a little bit of creativity you can document each element of an SPF record this way. ```js var SPF_RECORDS = TXT('@', [ 'v=spf1', 'ip4:1.2.3.0/24', // NY mail server 'ip4:4.3.2.0/24', // CO mail server 'include:_spf.google.com', // Google Apps 'include:mailgun.org', // Mailgun (requested by Ticket#12345) 'include:servers.mcsv.net', // MailChimp (requested by Ticket#54321) 'include:sendgrid.net', // SendGrid (requested by Ticket#23456) 'include:spf.mtasv.net', // Desk.com (needed by IT team) '~all' ].join(' ')); D('example.com', REG, DnsProvider('R53'), SPF_RECORDS, ) ``` ## Dual DNS Providers ```js D('example.com', REG, DnsProvider('R53'), DnsProvider('GCLOUD'), A('@', '1.2.3.4') ) // above zone uses 8 NS records total (4 from each provider dynamically gathered) // below zone will only take 2 from each for a total of 4. May be better for performance reasons. D('example2.com', REG, DnsProvider('R53',2), DnsProvider('GCLOUD',2), A('@', '1.2.3.4') ) // or set a Provider as a non-authoritative backup (don't register its nameservers) D('example3.com', REG, DnsProvider('R53'), DnsProvider('GCLOUD',0), A('@', '1.2.3.4') ) ``` ## Set default records modifiers ```js DEFAULTS( NAMESERVER_TTL('24h'), DefaultTTL('12h'), CF_PROXY_DEFAULT_OFF ); ```