DNS zone

DNS zone: Definition

A DNS zone contains the DNS records that determine which IP addresses and servers a domain or sub-domain points to. These records are stored on your Name Servers (NS) authoritarian. At LRobyou can manage your DNS records via the control panel Plesk.

Usefulness of the DNS zone

The DNS zone lets you configure various aspects of your domain. For example, for the domain site.tldthe DNS zone can contain the following information :

• The IP address to which site.tld tip (record type A).
• The IP address or domain name to which www.site.tld tip (recording A or CNAME).
• The server that manages the webmail.site.tld (registration A or CNAME).
• The inbox server for site.tld (registration MX).
• Servers authorized to send emails for the domain (registration TXT with the SPF).
• The encryption key for domain emails (registration TXT type DKIM).

Reading and understanding DNS entries

DNS records

A DNS zone is made up of several record types, each with a specific function. Here are the main types:

DNS record types

• A Pointing a domain or sub-domain to an IP address (IPv4).
• AAAA Pointing to an IP address in version 6 (IPv6).
• CNAME Alias that points a domain or sub-domain to another domain (like an alias).
• MX Indicates the email receiving server for a domain or sub-domain.
• NS Defines Name Servers (see page Name Servers) for a domain or sub-domain. Please note: for the main domain, this field is optional and has no authority. The NS are defined at registrar level, not at DNS zone level.
• TXT Contains information or rules interpreted by services, such as settings. SPF or DKIM for emails.

Rating

When you add a DNS entry, the display generally consists of three fields:

• The source, i.e. the sub-domain concerned (for the root domain, leave blank or enter "*" or "@" depending on the system).
• DNS record type (A, CNAME, MX, TXT, etc.)
• And the target, i.e. the destination (IP, domain name, TXT value, etc.).

DNS pointings are generally indicated in this form (without square brackets):

[source] [recording type] [target]

Exceptions :

• If the record concerns the main domain (with no sub-domains), the "source" field is empty or marked "@".
• For recordings MX (email reception servers), a priority field is added: for example, MX (0) where the number indicates the priority (0 being the highest).
• A Time To Live (TTL) value can sometimes be specified.

Example of a DNS zone

Let's take a concrete example with site.tld and the server ds.lrob.net :

• The main domain (site.tld) must point to 138.201.17.216 (IPv4) and 2a01:4f8:171:28e8::2 (IPv6). You create the entries :
  A 138.201.17.216
AAAA 2a01:4f8:171:28e8::2
• The sub-domain www.site.tld must point in the same way as the main domain :
  www CNAME site.tld.
• The inbox server for mail.site.tld points to the same IP addresses:
  mail A 138.201.17.216
mail AAAA 2a01:4f8:171:28e8::2The corresponding MX record :
  MX 0 mail.site.tld.
• The service webmail points to the server mail.site.tld :
  webmail CNAME mail.site.tld.
• The sub-domain dev must point to the local IP for development tests :
  dev A 127.0.0.1

A 138.201.17.216
AAAA 2a01:4f8:171:28e8::2
www CNAME site.tld.
mail A 138.201.17.216
mail AAAA 2a01:4f8:171:28e8::2
MX 0 mail.site.tld.
webmail CNAME mail.site.tld.
dev A 127.0.0.1

Note Recordings CNAME and MX usually end with a period. Plesk adds this point automatically.

Managing your DNS zone

DNS fields in Plesk

In Plesk, DNS is managed in the DNS settings :

• The first column, entitled Hostcorresponds to the source (sub-domain).
• The second column shows the Recording type.
• The third column, Valueindicates the target (the IP address or domain to point to).

Adding a DNS entry in Plesk

To add an entry :

1. See you in DNS settings under your domain in Plesk.
2. Click on Add a recording.
3. Select recording type (A, CNAME, MX, TXTetc.).
4. Enter the source (subdomain) and target (IP address or domain).
5. Click on Update at the top of the page to validate.

Modifying a DNS entry in Plesk

To modify an existing entry :

1. Click on the DNS record to be modified in the Host.
2. Modify the source and target values as required.
3. Click on Update to save changes.