DNS administration

The Domain Name System is a system for "translating" the various levels of a domain name into a numerical address (IP address), which can then be used to locate and communicate with servers and websites on the Internet. Without DNS, we would have to remember the IP address of every website we wanted to visit, instead of the domain name. For example, when you type http://www.mamut.com, the computer does not immediately know that it should look for Mamut's website. Instead, it sends a request to the nearest DNS server, which finds the correct IP address for "mamut.com". Then, your computer connects to the server with that IP number.

The zone file is a text file containing information about the different Internet services of your domain name. Each zone file contains a list of DNS records, also called resource records or just records that specify, for example, the domain name's name server or the mail server information. There are different types of records, for instance A (address) records, MX (e-mail) records and CName (alias) records.

You can easily edit the zone file of your domain via myMamut, but only advanced users should do so, since a small error could redirect your domain name to the wrong web server or prevent it from showing at all.

Via the DNS Administration screen in myMamut, you have a large number of options for administering the resource records of the zone file within your domain and services related to your domain name. The column Actions allows you to add, edit and remove records. Below is a description of the fields in the DNS Administration screen:

The A record is an abbreviation of Address. An address record is used to link a domain or hostname to an IP address. By entering a hostname in the Host field, you can link the host to a given IP address, which you enter into the Points to field.

An A record allows you to have a different hostname for your website pointing to different IP addresses, which could be useful if they are hosted on different servers. Note that an A record can only point to one IP address, but several A records can point to the same IP address.

Example: A record for mydomain.com

Host: www

Points to: 712.77.88.712

This A record will ensure that http://mydomain.com will point to the IP address 712.77.88.712.

Host: In this column you can view, add, edit or remove hosts for your domain's A records.

Points to: Here you can view, add, edit or remove IP addresses to which the A record will point.

TTL (Hours): In the column TTL (Hours), or Time to Live in hours, you can adjust the frequency with which changes to the A record should be made available for other servers. 24 hours is the most commonly used value.

CName means Canonical Name Record and is an alias used for representing an IP address. You should change your CName record if you wish to point a domain to a server without using an IP address. This might be useful if the IP address of the server it points to often changes.

CName records must be pointed to server names and not to IP addresses. You should not register more than one CName or A record (see above) which point to the same Host (registered in the column to the left). If several records point to the same host, the system will not be able to recognise which record should be used.

Example: CName record for mydomain.com

Host: blog

Points to: web.newweb.example.com

This CName will ensure that users visiting blog.mydomain.com will be directed to the server web.newweb.example.com.

Host: In this column you can view, add, edit or remove the host name to which the CName record should point.

TTL (Hours): In this column you can adjust the frequency with which changes to the CName should be made available for other servers. 24 hours is the most commonly used value.

The MX (Mail Exchanger) record specifies where the mail addressed to the domain is to be delivered. The MX record identifies the mail server that is responsible for handling e-mails within your domain name.

Example: MX record for mydomain.com

Host: @ (Note that in most cases the host for MX records is @)

Points to: mail1.mailserver.com.

Priority: 10

The MX record will direct all of the e-mail services for mydomain.com to the e-mail server mail1.mailserver.com with priority 10.

Priority: Here you can define the internal priority of your registered MX records. When more than one MX record is entered for any single domain name that is using more than one mail server, the MX records can be prioritised with numbers that indicate the order in which the mail servers should be used. This enables the use of primary and backup mail server.

TTL (Hours): In the column TTL (Hours), or Time to Live in hours, you can adjust the frequency with which changes to the MX record should be made available for other servers. 24 hours is the most commonly used value.

AAAA records are used in much the same way as A records (described above), with the main difference being that they locate IP addresses of the type IPv6 (128-bit) instead of addresses of the type IPv4 (32-bit), as are used by A records.

Example: AAAA record for mydomain.com

Host: @

Points to: 2001:620:600:6bf::2

The AAAA record will ensure that your preferred host is directed with IPv6 to your destination. This is an alternative to the IPv4 protocol.

Host: In this column you will find all hosts for your domain's registered AAAA records.

Points to: The column displays to which IP address(-es) the AAAA records of your domain points.

TTL (Hours): In the column TTL (Hours), or Time to Live in hours, you can adjust the frequency with which changes to the record should be made available for other servers. 24 hours is the most commonly used value.

The TXT record is an abbreviation of text. The TXT record is a customised text message that is directly registered in the zone file of your domain. TXT records can help you to verify your domain ownership and to prevent spam abuse.

A DNS search has to be performed in order to see this text. The text record is used by some companies to verify that customers have access to the zone file and are the real owners of the domain. The host name and value of the record will depend on the purpose of the record, and this might vary between different applications or services. Generally TXT entries are used as SPF records, or Sender Policy Framework records, an email validation system designed to prevent spam abuse.

Example: TXT record for mydomain.com

Host: for example @ or yourdomain.com. Can also be a subdomain.

Text value: Hello world

The TXT record will show "Hello world" when performing a specific DNS search for the TXT in the defined host.

Host: In this column you will find all hosts for your domain's registered TXT records.

TXT Value: This is the text that will be included in the zone file. The maximum length of the text is 256 characters.

TTL (Hours): In the column TTL (Hours), or Time to Live in hours, you can adjust the frequency with which changes to the record should be made available for other servers. 3600 (one hour) is the most common for TXT records, but 24 hours is default.

The SRV record is an abbreviation of Service. The SRV record relates to a particular service of the domain; it defines the location of servers for specific services.

Example: SRV record for mydomain.com

Host: _autodiscover._tcp.mydomain.com.

Points to: webmail.subdomain.com

Port: 443

Weight: 1

Priority: 100

The SRV record will make it easier to add new clients to Exchange services. When a new client is created on a system attached to a specific domain (mydomain.com) most of the configuration is gathered and added by the autodiscover service.

Host: In this column you will find all hosts for your domain's registered SRV records.

Points to: The column displays all domain names' of the target hosts for your domain's registered SRV records. There must be one or more IP address records for each name, and the name must not be an alias (CNAME).

Port: The port column displays the registered ports on the target hosts of the different services. The range is 0-65535.

Weight: The weight is a mechanism for server selection. This field specifies a relative weight for entries with the same priority. The range is 0-65535. The larger the weight, the higher the probability of being selected. You should use weight 0 when there is no server selection to be done.

Priority: Here you can define the internal priority of all registered SRV records.

The documentation may refer to services and/or functions that are not included within your solution. If you wish to order or get more information regarding this, please contact Mamut.

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