DNS Hosting FAQ

• What are Execulink’s DNS hosts?
• How can I tell who is hosting the DNS records for my domain?
• How do I change the DNS hosts for my domain?
• How do I make/request a DNS record update if Execulink is hosting my DNS records?
• What are some of the more common DNS records?
• How long does it take for a DNS record change to become live (active)?
• What is a DNS look-up and how do I perform one?
• What is a DNS zone file?

What are Execulink’s DNS hosts?

If Execulink is acting as your DNS host, these are the DNS servers/hosts that should be present in your domain’s WHOIS record:

• ns.execulink.com
• ns-bmi.execulink.com

How can I tell who is hosting the DNS records for my domain?

The WHOIS record for your domain contains the host names for your current DNS servers/hosts.

• How do I view the WHOIS record?

How do I change the DNS hosts for my domain?

If Execulink is the Registrar for your domain, send an e-mail to domadmin@execulinktelecom.ca with the domain name and the desired DNS hosts. DNS host updates can only be authorized by a valid contact for either the domain or the associated Execulink account.

If Execulink is not the Registrar for your domain, reach out to your current Registrar to find out their process for having DNS host changes completed.

Note: Because changing DNS hosts ultimately changes the DNS servers that are responsible for all of a domain’s DNS records, doing so has the potential to impact all DNS records for that domain, including the MX (mail) record.

• As such, if you are switching DNS hosts but have some DNS records that should not be changing, you’ll want to ensure that your new DNS host has all of the required DNS records in place for your domain prior to migrating the DNS hosting over to them.
• This would typically be accomplished by requesting a copy of your domain’s zone file from the current DNS host, and then providing that information to your future DNS host, along with details specifying which records need to be kept.

How do I make or request a DNS record update if Execulink is hosting my DNS records?

To have the DNS records for your domain updated when Execulink is serving as the DNS host, send an e-mail to domadmin@execulinktelecom.ca with the specifics, and a member of our Domain Administration team will make the DNS record update(s) for you.

DNS record changes can only be authorized by a valid contact for either the domain or the associated Execulink account. DNS record change requests received from other individuals will not be processed until they have been authorized by a valid contact.

What are some of the more common DNS records?

• MX Record: The Mail eXchanger (MX) record, also sometimes referred to as a ‘mail’ record, specifies where e-mail for a specific domain should be routed.
• Blank/Root Record: Refers to the root domain name with nothing tacked on to the front of it. (i.e. execulink.ca, execulink.com, etc.)
• WWW Record: Refers to any domain name with ‘www.’ affixed to the front, such as www.execulink.ca, www.execulink.com, etc. The WWW record is almost exclusively used for websites.
• A Record: Used to point a domain or subdomain to a specific IP address.
• CNAME Record: An alias used to map one host name (i.e. a domain or subdomain) to another. The two host names do not have to belong to the same root domain.
• TXT Record: A record that contains arbitrary text. Most commonly used for SPF and DKIM records, or to verify domain ownership for some services.
• PTR / Reverse DNS Record : This type of record is a bit of a departure from the norm, as it maps an IP address to a specific host name, rather than vice versa. Reverse DNS records are typically important for clients who send e-mail out through their own mail server, as many other mail servers on the internet will reject messages from servers which do not have a valid reverse DNS record in place.

How long does it take for a DNS record change to become live (active)?

Although DNS updates can appear ‘live’ within a few hours after a DNS record update has been made, it can take up to 48 hours for any change to completely propagate across the net. This interval is often referred to as the DNS propagation period.

During this propagation period, it is not uncommon for some servers to be aware of the recent updates, while others are not.

For example, let’s assume that a domain’s MX (mail) record has just been updated from originalMailHost.execulink.ca to newMailHost.execulink.ca. (Remember, an MX record specifies where e-mail for a domain should be routed.) During the DNS propagation period following that update, it’s not unusual for some mail hosts to route e-mail for that domain to newMailHost.execulink.ca, while others still route e-mail to originalMailHost.execulink.ca. Eventually, once the DNS update has propagated across all servers, all mail hosts should route mail appropriately to newMailHost.execulink.ca as desired.

What is a DNS lookup and how do I perform one?

A DNS lookup allows you to query a DNS server for a specific DNS record for a domain. For example, you could look up the MX (mail) record for a domain, or the ‘WWW’ record, etc.

There are a slew of online DNS lookup tools that can be used. These can be found pretty easily via a simple Google search.

Windows and MAC users can also make use of the nslookup command via the Command Prompt or Terminal programs respectively. Here are a few variations of that command for some of the more common DNS lookups:

• nslookup -ty=mx execulink.com – This will return the MX (mail) record for execulink.com.
• nslookup execulink.com – This will return the blank/root record for execulink.com.
• nslookup www.execulink.com – This will return the WWW record for execulink.com.
• nslookup ftp.execulink.com – This will return the DNS record for the sub-domain, ftp.execulink.com.
• nslookup -ty=txt execulink.com – This will return any TXT (text) records for execulink.com, which would include any SPF records.

Note: We are using execulink.com as our example domain in the commands above. To perform the lookups for a different domain, simply replace execulink.com with the preferred domain.

What is a DNS zone file?

A zone file is just a technical term for the file that resides on a DNS server that contains the specific DNS records for a domain.