DNS records
  1. Ref
    1. https://my.bluehost.com/cgi/help/508
    2. https://support.google.com/a/answer/48090?hl=en
  2. Sample from godaddy
    1. http://i.imgur.com/JHgynBe.png
  3. Explain
    1. @: root domain (ex: golery.com)
    2. TXT: any text info, which can be used for google verification (for exampl)
    3. CName: canonica name : forward a subdomain to another domain (examle forward to amzon public domain name of EC instances)
    4. A: address: foward a subdomain to an IP address
    5. NS: nameserver 
      We can use default name serer of goddy / name cheap Or declare the nameserver of amazone Route53.
      If we choose external name server (ex: route52, the configure of records A, CName can only be done on external DNS)
  4. Amazon Route 53
    1. A name server. If you don't like namecheap server. You can config name cheap to use Route 53 name server directly
  5. To point to Amazone ECS
    1. Create elastics IP, assign it to a running instance. Elastic IP is not changed even if instance is restarted.
    2. Simple way: Name cheap server, create 2 A records which point to ECS2 elastic IP:
      1 A record for @ (root) and and 1 A record for www
    3. Comlext: 
      1. Declare namecheap to use Route53 name server
      2. Create 2 A records in Route 53 to Elastic I