{"id":30615,"date":"2022-07-16T14:51:25","date_gmt":"2022-07-16T14:51:25","guid":{"rendered":"https:\/\/www.devopsschool.com\/blog\/?p=30615"},"modified":"2022-12-23T05:52:22","modified_gmt":"2022-12-23T05:52:22","slug":"what-is-dns-records-most-common-dns-records","status":"publish","type":"post","link":"https:\/\/www.devopsschool.com\/blog\/what-is-dns-records-most-common-dns-records\/","title":{"rendered":"What is DNS records? Most Common DNS records?"},"content":{"rendered":"\n
DNS Record<\/th>Description<\/th><\/tr>
A<\/td>Maps domain names to IPv4 addresses<\/td><\/tr>
AAAA<\/td>Maps domain names to IPv6 addresses<\/td><\/tr>
CNAME<\/td>Redirects a domain to a different domain<\/td><\/tr>
PTR<\/td>Resolves IPv4 or IPv6 addresses to domain names<\/td><\/tr>
NS<\/td>Provides a list of the authoritative name servers responsible for the domain<\/td><\/tr>
MX<\/td>Provides the domain names of mail servers that receive emails on behalf of a domain<\/td><\/tr>
SOA<\/td>Provides important details about a DNS zone; required for every DNS zone<\/td><\/tr>
TXT<\/td>Provides any type of descriptive information in text format<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

What are the most common types of DNS record?<\/h2>\n\n\n\n
  • A record<\/strong>\u00a0– The record that holds the IP address of a domain.\u00a0<\/li>
  • AAAA record<\/strong>\u00a0– The record that contains the IPv6 address for a domain (as opposed to A records, which list the IPv4 address).<\/li>
  • CNAME record<\/strong>\u00a0– Forwards one domain or subdomain to another domain, does NOT provide an IP address.\u00a0<\/li>
  • MX record<\/strong>\u00a0– Directs mail to an email server.\u00a0<\/li>
  • TXT record<\/strong>\u00a0– Lets an admin store text notes in the record. These records are often used for email security.\u00a0<\/li>
  • NS record<\/strong>\u00a0– Stores the name server for a DNS entry.<\/li>
  • SOA record<\/strong>\u00a0– Stores admin information about a domain.\u00a0<\/li>
  • SRV record<\/strong>\u00a0– Specifies a port for specific services.\u00a0<\/li>
  • PTR record<\/strong>\u00a0– Provides a domain name in reverse-lookups.\u00a0<\/li><\/ul>\n\n\n\n

    What are some of the less commonly used DNS records?<\/h2>\n\n\n\n
    • AFSDB record<\/strong>\u00a0– This record is used for clients of the Andrew File System (AFS) developed by Carnegie Melon. The AFSDB record functions to find other AFS cells.<\/li>
    • APL record<\/strong>\u00a0– The \u2018address prefix list\u2019 is an experiment record that specifies lists of address ranges.<\/li>
    • CAA record<\/strong>\u00a0– This is the \u2018certification authority authorization\u2019 record, it allows domain owners state which certificate authorities can issue certificates for that domain. If no CAA record exists, then anyone can issue a certificate for the domain. These records are also inherited by subdomains.<\/li>
    • DNSKEY record<\/strong>\u00a0– The \u2018DNS Key Record\u2019 contains a\u00a0public key\u00a0used to verify\u00a0Domain Name System Security Extension (DNSSEC)\u00a0signatures.<\/li>
    • CDNSKEY record<\/strong>\u00a0– This is a child copy of the DNSKEY record, meant to be transferred to a parent.<\/li>
    • CERT record<\/strong>\u00a0– The \u2018certificate record\u2019 stores public key certificates.<\/li>
    • DCHID record<\/strong>\u00a0– The \u2018DHCP Identifier\u2019 stores info for the Dynamic Host Configuration Protocol (DHCP), a standardized network protocol used on IP networks.<\/li>
    • DNAME record<\/strong>\u00a0– The \u2018delegation name\u2019 record creates a domain alias, just like CNAME, but this alias will redirect all subdomains as well. For instance if the owner of \u2018example.com\u2019 bought the domain \u2018website.net\u2019 and gave it a DNAME record that points to \u2018example.com\u2019, then that pointer would also extend to \u2018blog.website.net\u2019 and any other subdomains.<\/li>
    • HIP record<\/strong>\u00a0– This record uses \u2018Host identity protocol\u2019, a way to separate the roles of an IP address; this record is used most often in mobile computing.<\/li>
    • IPSECKEY record<\/strong>\u00a0– The \u2018IPSEC key\u2019 record works with the\u00a0Internet Protocol Security (IPSEC), an end-to-end security protocol framework and part of the Internet Protocol Suite\u00a0(TCP\/IP).<\/li>
    • LOC record<\/strong>\u00a0– The \u2018location\u2019 record contains geographical information for a domain in the form of longitude and latitude coordinates.<\/li>
    • NAPTR record<\/strong>\u00a0– The \u2018name authority pointer\u2019 record can be combined with an\u00a0SRV record\u00a0to dynamically create URI\u2019s to point to based on a regular expression.<\/li>
    • NSEC record<\/strong>\u00a0– The \u2018next secure record\u2019 is part of DNSSEC, and it\u2019s used to prove that a requested DNS resource record does not exist.<\/li>
    • RRSIG record<\/strong>\u00a0– The \u2018resource record signature\u2019 is a record to store digital signatures used to authenticate records in accordance with DNSSEC.<\/li>
    • RP record<\/strong>\u00a0– This is the \u2018responsible person\u2019 record and it stores the email address of the person responsible for the domain.<\/li>
    • SSHFP record<\/strong>\u00a0– This record stores the \u2018SSH public key fingerprints\u2019; SSH stands for Secure Shell and it\u2019s a cryptographic networking protocol for secure communication over an unsecure network.<\/li><\/ul>\n\n\n\n
      \"\"<\/figure>\n\n\n\n

      A Record<\/h2>\n\n\n\n

      A (address) records<\/strong> are one of the most basic and commonly used DNS record types. They translate domain names and store them as IP addresses. A records can only hold IPv4 addresses.<\/p>\n\n\n\n

      An example of an A record is:<\/p>\n\n\n\n

      Domain name:<\/strong><\/td>Record type:<\/strong><\/td>Value:<\/strong><\/td>TTL<\/strong><\/td><\/tr>
      example-website.com @<\/td>A<\/td>192.0.0.1<\/td>14400<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

      In the example above, the record is made up of the following elements:<\/p>\n\n\n\n

      • Domain name:<\/strong> Contains the domain name of the website. The “@” symbol indicates that the record contains the root domain name.<\/li>
      • Record type:<\/strong> Indicates the usage of an A record type.<\/li>
      • Value:<\/strong> Contains the IP address associated with the domain name.<\/li>
      • TTL:<\/strong> Lists the record’s TTL (Time to Live) in seconds. The default value is 14400, which means the record expires after 14400 seconds (240 minutes).<\/li><\/ul>\n\n\n\n

        CNAME Record<\/h2>\n\n\n\n

        A CNAME (canonical name) record<\/strong> is used instead of an A record if a domain is an alias for another domain. Because of this, all CNAME records point to a domain instead of an IP address.<\/p>\n\n\n\n

        For example, in a domain called alias-domain.com<\/strong> which works as an alias for real-domain.com<\/strong>, a CNAME record for would look like this:<\/p>\n\n\n\n

        Domain name:<\/strong><\/td>Record type:<\/strong><\/td>Value:<\/strong><\/td>TTL<\/strong><\/td><\/tr>
        alias-domain.com @<\/td>CNAME<\/td>real-domain.com<\/td>14400<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

        This record contains:<\/p>\n\n\n\n

        • Domain name:<\/strong> Contains the alias domain name. The “@” symbol shows that this is a root domain name.<\/li>
        • Record type:<\/strong> Shows that this is a CNAME record.<\/li>
        • Value:<\/strong> Contains the real domain name that the alias domain is pointing to.<\/li>
        • TTL:<\/strong> Time left until the record expires.<\/li><\/ul>\n\n\n\n

          CNAME records usually contain subdomains that point to a domain’s A or AAAA record. This prevents having to create an extra A or AAAA record for each subdomain.<\/p>\n\n\n\n

          It is not recommended to have CNAME records pointing to other CNAME records, as this creates unnecessary steps to the DNS lookup process.<\/p>\n\n\n\n

          MX Record<\/h2>\n\n\n\n

          MX (mail exchange) records<\/strong> store instructions for directing emails to mail servers following the SMTP protocol. An MX record might look like:<\/p>\n\n\n\n

          Domain name:<\/strong><\/td>Record type:<\/strong><\/td>Priority:<\/strong><\/td>Value:<\/strong><\/td>TTL:<\/strong><\/td><\/tr>
          example-website.com @<\/td>MX<\/td>10<\/td>mail.example-website.com<\/td>14400<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

          In this example:<\/p>\n\n\n\n

          • Domain name:<\/strong>\u00a0Specifies the domain name.<\/li>
          • Record type:<\/strong>\u00a0Indicates an MX record.<\/li>
          • Priority:<\/strong>\u00a0Specifies preference when delivering mail, with lower values having higher priority. If there is a failure to deliver, the mail will be redirected to a lower-priority email server.<\/li>
          • Value:<\/strong>\u00a0Specifies an email server for the domain name.<\/li>
          • TTL:<\/strong>\u00a0Time left to record expiration.<\/li><\/ul>\n\n\n\n

            PTR Record<\/h2>\n\n\n\n

            PTR (pointer) records<\/strong> serve as an inverse of A or AAAA records. They map IP addresses to domain names and help perform reverse DNS lookups.<\/p>\n\n\n\n

            PTR records store IP addresses in reverse:<\/p>\n\n\n\n

            • IPv4 addresses are saved with the segments in reverse order.<\/li>
            • IPv6 addresses are saved in the reverse order of hexadecimal digits.<\/li><\/ul>\n\n\n\n

              SOA Record<\/h2>\n\n\n\n

              The SOA (start of authority) record<\/strong> holds important information about a domain or zone. These records are required by IETF standards and are an important element of zone transfers.<\/p>\n\n\n\n

              SOA records detail the following zone properties:<\/p>\n\n\n\n

              • Name:<\/strong>\u00a0Name of the primary DNS server for the zone. Each primary server should also have a matching NS record.<\/li>
              • Record type:<\/strong>\u00a0Indicates that this is an SOA record.<\/li>
              • MNAME:<\/strong>\u00a0Specifies the primary nameserver for the zone.<\/li>
              • RNAME:<\/strong>\u00a0The email address of the person responsible for the zone.<\/li>
              • Serial:<\/strong>\u00a0The zone’s serial number.<\/li>
              • Refresh:<\/strong>\u00a0The number of seconds between checking for record updates.<\/li>
              • Retry:<\/strong>\u00a0The number of seconds before asking an unresponsive primary nameserver for another update.<\/li>
              • Expire:<\/strong>\u00a0How long to retry updating an unresponsive nameserver before stopping.<\/li>
              • TTL:<\/strong>\u00a0Time until record expires.<\/li><\/ul>\n\n\n\n

                SRV Record<\/h2>\n\n\n\n

                SRV (service) records<\/strong> store host and port information for internet services, such as email or VoIP. Some internet protocols need valid SRV records to function.<\/p>\n\n\n\n

                SRV records hold the following information:<\/p>\n\n\n\n

                • Service:<\/strong>\u00a0Symbolic name for a service.<\/li>
                • Protocol:<\/strong>\u00a0Specifies if the service is using TCP or UDP protocols.<\/li>
                • Name:<\/strong>\u00a0Stores a domain name.<\/li>
                • TTL:<\/strong>\u00a0Time left until record expires.<\/li>
                • Class:<\/strong>\u00a0Can contain\u00a0IN<\/strong>\u00a0(default),\u00a0CH<\/strong>\u00a0(used for querying DNS server versions), or\u00a0HS<\/strong>\u00a0(uses DNS functionality to provide access to databases).<\/li>
                • Type:<\/strong>\u00a0Specifies record type as SRV.<\/li>
                • Priority:<\/strong>\u00a0Determines which server is looked at first, with lower values giving higher priority.<\/li>
                • Weight:<\/strong>\u00a0Determines which server is looked at first if more than one has the same priority value. Higher values give more priority.<\/li>
                • Port:<\/strong>\u00a0The TCP or UDP port the service is running on.<\/li>
                • Target:<\/strong>\u00a0The canonical hostname for the machine providing the service.<\/li><\/ul>\n\n\n\n

                  TXT Record<\/h2>\n\n\n\n

                  TXT (text) records<\/strong> are used to store descriptive text. They are often used in combination with other record types to provide additional information that doesn’t fit the format of other records.<\/p>\n\n\n\n

                  Domain name:<\/strong><\/td>Record type:<\/strong><\/td>Value:<\/strong><\/td>TTL:<\/strong><\/td><\/tr>
                  example-website.com @<\/td>TXT<\/td>Example text.<\/td>14400<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

                  The example above shows a typical TXT record. It contains the following elements:<\/p>\n\n\n\n

                  • Domain name:<\/strong> Specifies a domain name.<\/li>
                  • Record type:<\/strong> Shows that this is a TXT record.<\/li>
                  • Value:<\/strong> Stores a user-defined text string.<\/li>
                  • TTL:<\/strong> Time until record expires.<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"

                    DNS Record Description A Maps domain names to IPv4 addresses AAAA Maps domain names to IPv6 addresses CNAME Redirects a domain to a different domain PTR Resolves IPv4 or IPv6… <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_joinchat":[],"footnotes":""},"categories":[2],"tags":[],"class_list":["post-30615","post","type-post","status-publish","format-standard","hentry","category-uncategorised"],"_links":{"self":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/30615","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/comments?post=30615"}],"version-history":[{"count":2,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/30615\/revisions"}],"predecessor-version":[{"id":30619,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/30615\/revisions\/30619"}],"wp:attachment":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/media?parent=30615"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/categories?post=30615"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/tags?post=30615"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}