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DNS Management

What is DNS?
DNS, Domain Name System, is simply the "phone book" of the internet. For instance, if you type in http://www.1stdomains.co.uk it then looks up your "post code (website address)" and comes back with 213.146.186.41 which is where the http://www.1stdomains.co.uk website is stored.

Example of a DNS zone file:
Domain DNS Record Prioirty Information
1stusb.co.uk. SOA control.1stdomains.co.uk. root.control.1stdomains.co.uk. (2008022601 7200 3600 604800 3600)
1stusb.co.uk. MX 10 greylist.1stdomains.co.uk.
1stusb.co.uk. A 213.146.186.31
1stusb.co.uk. NS cdns01.1stdomains.co.uk.
1stusb.co.uk. NS cdns02.1stdomains.co.uk.
1stusb.co.uk. NS cdns03.1stdomains.co.uk.
ftp.1stusb.co.uk. CNAME 1stusb.co.uk.
mail.1stusb.co.uk. A 213.146.186.31
pop3.1stusb.co.uk. A 213.146.186.31
smtp.1stusb.co.uk. A 213.146.186.31
webmail.1stusb.co.uk. A 213.146.186.31
www.1stusb.co.uk. A 213.146.186.31
1stusb.co.uk. SOA control.1stdomains.co.uk. root.control.1stdomains.co.uk. (2008022601 7200 3600 604800 3600)

Reverse DNS is set up automatically for all domains.


Breakdown of each type of record for your knowledge.

Record Type Description
A records An "A" record (v4) is a translation to an IPV4 IP adress. www. Mail.
MX records Mail eXchanger record which points to an "A" record which in turn points to an IP address.
TXT records A TXT record is usually used to display SPF records which can be part of a Spam protection system amongst other uses.
Custom SOA records @ IN SOA nameserver.place.dom. postmaster.place.dom.
1 ; serial number
3600 ; refresh [1h]
600 ; retry [10m]
86400 ; expire [1d]
3600 ) ; min TTL [1h]

The SOA resource record contains the following information:

Source host - The host where the file was created.

Contact e-mail - The e-mail address of the person responsible for administering the domain's zone file. Note that a "." is used instead of an "@" in the e-mail name.

Serial number - The revision number of this zone file. Increment this number each time the zone file is changed. It is important that the value is increased each time a change is made, this then causes the changes to be distributed to any secondary DNS servers.

Refresh Time - The time, in seconds, a secondary DNS server waits before querying the primary DNS server's SOA record to check for changes. When the refresh time expires, the secondary DNS server requests a copy of the current SOA record from the primary. The primary DNS server complies with this request. The secondary DNS server compares the serial number of the primary DNS server's current SOA record and the serial number in it's own SOA record. If they are different, the secondary DNS server will request a zone transfer from the primary DNS server. The default value is 3,600.

Retry time - The time, in seconds, a secondary server waits before retrying a failed zone transfer. Normally, the retry time is less than the refresh time. The default value is 600.

Expire time - The time, in seconds, that a secondary server will keep trying to complete a zone transfer. If this time expires prior to a successful zone transfer, the secondary server will expire its zone file. This means the secondary will stop answering queries, as it considers its data too old to be reliable. The default value is 86,400.

Minimum TTL - The minimum time-to-live value applies to all resource records in the zone file. This value is supplied in query responses to inform other servers how long they should keep the data in cache. The default value is 3,600.
NS records A NS record tells name servers which servers are in charge of a given domain zone
CNAME records An alias record of an "A" record.
AAAA records An "AAAAA" record (V6 is a translation to an IPV6 IP adress.
SRV records The SRV record is a Domain Name System (DNS) resource record. this is used to identify computers that host specific services. SRV resource records are used to locate domain controllers for Active Directory. To verify SRV locator resource records for a domain controller, use one of the following methods.



All of the team here at 1stdomains.co.uk strongly believe that you should have full access over your DNS records / zone files. Our system will allow you to navigate around your DNS with ease and comfort.

All DNS entries that you or our team make to your domain will be updated through the whole of the network and mirror systems within 30 Minutes of the change.

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