- domain registrar is normally the place where you purchased/obtained your domain
- Your registrar could be a business that only does domain registration or even your web host itself.
- whenever a request for a domain is made, the registrar is the first place that gets referenced for information.
- they identify what set of servers any requests should reference in order to obtain a domain’s DNS records.
- Your domain should have it’s nameservers pointed to wherever you are intending to manage your site’s DNS records.
- A DNS Record is a single entry that gives the zone instructions on how to handle any given request based on type.
- used to point a domain or subdomain to an IP address.
- record maps a name to one or more IP addresses, when the IP are known and stable.
- use an A record if you manage what IP addresses are assigned to a particular machine or if the IP are fixed (this is the most common case)
- used to point a host/name to another host/name.
- record maps a name to another name.
- use a CNAME record if you want to alias a name to another name, and you don’t need other records (such as MX records for emails) for the same name
- specifies which server(s) to attempt to use to deliver mail to when this type of request is made to the domain.
- A DNS Record ‘s name is the descriptor and effective subdomain of that entry
- There exist a few special cases you should be aware of.
- A record that has nothing in the name slot gets used for all requests made to the base/naked form of the domain.
- e.g. pressable.com and www.pressable.com are two different DNS records with separate values for their name. The www.pressable.com DNS record uses “www” as its record name and pressable.com uses nothing/blank for its record name.
- Some DNS management systems use the @ symbol in the “name” slot instead of the blank name entry. This is important because it allows the use of @ as another record’s value/data, meaning the other record will refer to the value of the base/naked form of the domain to know where to point.
- you always wanted www.pressable.com to point at the same place as presable.com. You could just set them individually to point at the same place and manage them separately, but since the @ symbol represents the base/naked DNS record, you could set the www DNS record entry to have a value/data of @ and it will always refer to and use the value of the @ name record when being requested.
- This symbol is used as an indicator that the record named * should be used in place of any record that isn’t specified. These can be used when you would like to direct subdomains that do not exists somewhere where they can be accounted for or handled.
- A DNS Record’s value or data is the information that tells the DNS record where you want it to point, or in some cases, what you want it to do.
- A Records and CNAMEs, the data/value represents the IP or domain, respectively, that the record name is pointed at and should refer to to figure out where to go next.
- In MX records, the value/data information indicates what mail servers email should be routed to.
- SPF records use the value/data field so specify what servers are allowed to legitimately use your domain name for the sending of emails.
- how long a DNS record will be cached before it needs to be refreshed
- A DNS Zone is like a container of all the DNS records for a specific domain and only that domain.
- For example: pressable.com, www.pressable.com, blog.pressable.com, and mail.pressable.com are four DNS Records inside a single DNS Zone for pressable.com.