What are Name servers ?

Name servers are computer servers which implement the DNS service protocol.

For your domain name to function correctly you need to assign (delegate) two or more name servers to it.

By default, domains registered with Domainmonster.com use the Domainmonster.com name servers. Using the Domainmonster.com name servers allows you to use our DNS Management, Web Forwarding, Email Forwarding, My Home Page, and POP3 Mailbox services.

Should you wish another provider to carry out these functions for you (for example if you wish to host your website elsewhere), you can change your domains’ name servers to those of another provider.

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What is DNS?

DNS stands for Domain Name System.

The main function of DNS is to translate domain names into IP Addresses, which computers can understand. It also provides a list of mail servers which accept Emails for each domain name.

Each domain name in DNS will nominate a set of name servers to be authoritative for its DNS records. This is where all other name servers will be pointed when looking for information about the domain name

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What are 3rd Party Name Servers?

Third party name servers refer to any name servers apart from the Domainmonster.com name servers.

Typically these name servers are provided by another company. By using 3rd party name servers, you are delegating responsibility for your domain names’ DNSmanagement to the provider of those name servers.

Using 3rd party name servers will mean that you can no longer use our DNS Management, Web Forwarding, Email Forwarding, My Home Page or POP3 Mailbox services for the domain names in question. Management of billing, invoicing and renewal will still remain with Domainmonster.com. This is because changing your name servers does not constitute a transfer of your domain to another registrar.

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What is a glue record?

A glue record is the IP address of a name server held at the

Domain Name registry.

Glue records are required when you wish to set the name servers of a domain name to a hostname under the domain name itself.

For example if you wished to set the name servers of example.com to ns1.example.com and ns2.example.com you would need to also provide the glue records (i.e. the IP addresses) for ns1.example.com and ns2.example.com.

If you did not provide the glue records for these name servers then your domain name would not work as anyone requiring DNS information for it would get stuck in a loop:

What is the name server for example.com? -> ns1.example.com

What is the IP address of ns1.example.com? -> don't know, try looking at name server for example.com

What is the name server for example.com? -> ns1.example.com

...and so on.

With the glue record in place the registry will hold the IP address and the loop will not occur:

What is the name server for example.com? -> ns1.example.com

What is the IP address of ns1.example.com? -> [IP Address]

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What are cached DNS records?

To speed up DNS most name servers on the internet will cache (remember) DNS records themselves, so that they do not have to look up records each time they require them.

When you visit a website, it is probable that your ISP's name servers will remember the IP Address, so that the next time you (or someone else) requests that website, the IP address can be retrieved more quickly.

In this instance your ISP's name server is using a cached DNS record. It will use this cached record for a period of time, after which it will retrieve the record again. It will again cache the record and the cycle will repeat.

This is why when you make changes to your DNS some people will not see the change immediately as they may well be seeing a cached record.

We recommend allowing 48 hours for name servers around the world to delete their cached record, and request the new updated one.

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What is an FQDN (Fully Qualified Domain Name)?

A FQDN (fully qualified domain name) is an entire domain name address, includinghostname, domain name and top-level domain.

For example when entering a name server you will need to provide an FQDN such as ns1.domainmonster.com. Technically a FQDN requires a dot after the top-level domain (e.g. ns1.domainmonster.com.) to indicate the empty domain at the end of the address. However there is no need to add this final dot when using our control panel features.

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What is a hostname?

A hostname is any name placed to the left of your domain name which resolves to an IP address or other FQDN.

For example in the FQDN www.domainmonster.com "www" is the hostname.

The word hostname is used because on a local network each machine (host) is usually assigned a name to make it easily identifiable. The same principle is applied to domain names, where a name is applied to save the need to remember an IP Address.

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What are public and private IP addresses?

A public IP address is any IP address that is accessible via the Internet. There are certain ranges of IP addresses that are reserved as private IP IP Addresses. These cannot be reached via the Internet. These private IP addresses include:

10.0.0.1 - 10.255.255.255 (reserved for local networks)

127.0.0.1 - 127.255.255.255 (loopback address and reserved for local networks)

172.16.0.1 - 172.16.255.255 (reserved for local networks)

192.168.0.1 - 192.168.255.255 (reserved for local networks)

169.254.0.0 - 169.254.255.255 (reserved for automatic private addressing)

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How can I modify the DNS for a domain?

To manage DNS for your domain via your Domainmonster.com account, our name servers must be assigned to your domain. Within the control panel for the relevant domain and choose 'Manage DNS'. From here you can add, delete and amend all DNS records:

A-Records

CNAME Records

MX Records

TXT Records (SPF)

NS Records

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What is an A Record?

An A-record (address record) maps a hostname to an

IP Address.

For example you may want to add an A-record for the hostname "www" and IP address 217.28.124.132 so that www.yourdomain.com resolves to the IP address 217.28.124.132 where your website is hosted.

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What is an AAAA Record?

An AAAA-record (address record) maps a hostname to an

IPv6 Address.

For example you may want to add an AAAA-record for the hostname "www" and IP address 2001:0db8:85a3:0042:0000:8a2e:0370:7334 so that www.yourdomain.com resolves to the IP address 2001:0db8:85a3:0042:0000:8a2e:0370:7334 where your website is hosted.

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What is a CNAME record?

A CNAME (canonical name) record maps a host name to another hostname or FQDN.

For example you may want to add a CNAME record for hostname "wwww" to "www" so that anyone mistyping an additional "w" in your website address will still get to the site at www.yourdomain.com.

You could also add a CNAME record for hostname "search" and FQDN "www.google.com" so that anyone visiting search.yourdomain.com would be presented with www.google.com.

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What is an MX record?

An MX record comprises a FQDN and a priority. The priority is simply a number which is used to choose which mail server to use if multiple MX records exist for a domain name. A mail server trying to send an email to you will always try the lowest number priority first.

Additionally an MX record has a host name to allow Email Addresses with subdomains. The hostname is usually left blank to specify the mail server for the domain name on its own.

If you have a mail server at mail.somemailserver.com and you want to add this for your domain name mydomain.com, you would add an MX record with a blank hostname, an FQDN of mail.somemailserver.com, and a priority, e.g. 10.

This record would mean that any emails addressed to @mydomain.com would be delivered to the server at mail.somemailserver.com.

If you had a backup mail server that you only wanted mail delivered to in case of a problem with your main mail server, you would add another MX record with an FQDN of mail.someothermailserver.com and a higher priority number( e.g. 20.)

This record would mean that any emails that were addressed to @mydomain.com which could not be delivered to the server at mail.somemailserver.com would be delivered to the server at mail.someothermailserver.com.

Adding a hostname into the MX record simply means that you are specifying the mail servers for a subdomain.

For example adding an MX record for hostname "london", FQDN mail.mylondonmailserver.com with priority 10 would mean that any emails addressed to @london.mydomain.com would be delivered to the mail server mail.mylondonmailserver.com. It would not affect any emails addressed to @mydomain.com.

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What is a TXT record?

A TXT (text) record is used to hold some text information. You can put virtually any free text you want within a TXT record.

A TXT record has a hostname so that you can assign the free text to a particularhostname/zone. The most common use for TXT records is to store SPF (sender policy framework) records and to prevent emails being faked to appear to have been sent from you.

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What is an NS record?

An NS (name server) record allows you to delegate a subdomain of your domain to another name server.

For example you have the domain mydomain.com which is using theDomainmonster.com name servers. You decide that you want your own name server (myns.mydomain.com), for which you have already added an A-record, to look after the DNS for a subdomain on your domain: extranet.mydomain.com.

To do this, you would add an NS record for hostname/Zone "extranet" with the name server address "myns.mydomain.com". If someone therefore wants any DNS information about extranet.mydomain.com, our Domainmonster.com name servers will send them in the direction of the server at myns.mydomain.com.

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What is an SPF (sender policy framework) record?

An SPF record is a Sender Policy Framework record. An SPF record is actually a specific type of TXT record.

An SPF record is used to stop people receiving forged email. By adding an SPF record into your DNS configuration any mail servers receiving email, that is allegedly from you, will check that the email has come from a trusted source. The trusted sources are provided by the SPF record that you set up.

More information on SPF records can be found on the Open SPF website.

There is also an SPF Wizard which helps you to create the SPF/TXT record for you.

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What happens if I edit my DNS?

If you edit or add DNS records, you may affect services currently configured against your domain. If you are not sure what will be affected by a specific record, please don’t hesitate to contact the customer support team who will be happy to help you.

From <http://faq.domainmonster.com/dns/edit_dns/>

How can I reset the DNS to default?

If you would like to have your DNS settings for your domain reset to the default configuration simply log in to your control panel within the members area. Select the relevant domain and click the 'Manage' button. Select 'Manage DNS' from the central menu and choose 'DNS Zone Reset'.

Resetting your DNS Zone configuration cannot be undone.

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Why can’t I edit the DNS for my domain?

If the 'Manage DNS' feature is greyed out within your control panel this means that you are using third party name servers. If you would like to use Domainmonster.com for DNS management

, you need to choose the 'Use Domainmonster.com Name Servers' option within the 'Name Servers' interface of the control panel.

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Where can I manage my DNS within my control panel?

To manage DNS, first you need to specify the domain that you wish to manage its DNS settings. Then from the domain control panel just select "Manage DNS".

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How long will changes to the DNS take to update?

All changes made to DNS records within the "Manage DNS" section of your control panel are instantly updated on the Domainmonster.com DNS servers. However it can take between 12 and 24 hours for all ISP's name servers to refresh cached records.

Changes to the name servers for a domain name can take between 24 and 48 hours to propagate.

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What does "resolve" mean in terms of DNS?

An A-record exists which maps the hostname ‘www’ for the Domain‘yourdomain.com’ to an IP address 217.28.124.132. If you wished to view the website at ‘www.yourdomain.com’, your browser would require the IP Address of ‘www.yourdomain.com’ in order to connect to the hosting server. The IP Addressfor ‘www.yourdomain.com’ would be requested through DNS, and if successful then you would say that “‘www.yourdomain.com’ resolved to 217.28.124.132”.

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Why am I getting an error adding a DNS record?

There could be many reasons that a DNS update is failing. Below is a list of rules that your updates must comply to.

Please also be aware that we do not support Relative Domain Names or Wildcards.

A Records:

- Root Hostnames are allowed.

- You can have multiple A Records with the same Hostname, as long as they have different IP Addresses.

- A Hostname that clashes with a CNAME alias is not permitted

CNAME records:

- Root Aliases are not permitted.

- You can only have a single CNAME per Alias

- Aliases that clash with Hostnames for A , MX, TXT and NS records are not permitted.

MX records:

- Root Hostnames are allowed.

- You can have multiple MX records with the same Hostname, as long as the Server Addresses are different.

- Hostnames that clash with CNAME Aliases are not permitted.

- Preference values do not have any restrictions.

TXT records:

- Root Hostnames are allowed.

- You can have multiple TXT records with the same Hostname, as long as the Comment/Text is different.

- Hostnames that clash with CNAME Aliases are not permitted.

NS records:

- Root Hostnames are not permitted.

- You can have multiple NS records with the same Hostname/Zone, as long as theName server address is different.

- Hostnames that clash with CNAME Aliases are not permitted.

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What is an SRV record?

An SRV record is an advanced type of record which allows you to specify services that you have on your domain. Use an SRV record if a certain application or piece of software requires it.

For example, you might want to specify that you have FTP access on your domain. You could use a CNAME to create a subdomain, but this would only tell people the address of the server. An SRV record will tell people the following information in addition to the address:

The Service Name (e.g. _ftp)

The Protocol (e.g. _tcp)

The Port Number that this service is on (e.g. 21)

The Priority (An arbitrary number which tells people which record to pick if you have several SRV records with the same Name and Protocol)

The Weight (Another arbitrary number which tells people which records should be used more often if you have several SRV records with the same Name and Protocol

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http://faq.domainmonster.com/dns/srv/

	Created by qhayum.05 about 9 years ago

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