This article explains in detail DNS record types ALIAS, CNAME, and DNAME. A general guide to DNS records and their setup in the customer administration can be found in the article DNS – Domain Records.
In this article, you will learn:
- How an ALIAS record works
- How a CNAME record works
- How a DNAME record works
- Common problems
- Frequently asked questions
ALIAS Record Type
An ALIAS record (sometimes called ANAME) is used to point the main domain to an existing domain or subdomain. Some hosting providers prefer this record type over A and AAAA records.
If you need to point your own subdomain to a provider’s domain or subdomain, use a CNAME record.
An ALIAS record works only on primary DNS servers. When the record is created, the system automatically looks up the currently set A/AAAA records for the ALIAS value (if they exist) and inserts them into DNS. Updates are handled by automatic synchronization, so record freshness depends on the ALIAS TTL and the TTL of the relevant records on the source domain (or on other domains in the chain, if applicable), as well as other circumstances.
We do not guarantee the synchronization time of A/AAAA records with ALIAS.
Entering ALIAS Records
A general guide to setting up DNS records in the customer administration can be found in the article DNS – Domain Records.
If the domain uses different DNS servers, changes to VEDOS records will not affect its behavior.
An ALIAS record must be the main domain. The name field must therefore be empty.
In the data field, enter the name of the domain or subdomain that the main domain should mask. Omit the protocol (http, https) from the name. Do not enter IP addresses in the data field either; those are entered using A and AAAA records.
Name TTL Type Data
(leave empty) 300 ALIAS (domain or subdomain name)
Example of an ALIAS Record
Example: (Not actually functional) ALIAS record for default.wedos.net.
CNAME Record Type
CNAME records are used to point a subdomain to an existing domain or subdomain. The most common uses include pointing subdomains to web hosting that requires or supports this type of routing, or to services such as FTP, SMTP, POP/IMAP.
Because CNAME practically changes one subdomain into another (sub)domain, you cannot create other record types for a subdomain that already has a CNAME record, and vice versa.
A CNAME record must also point to a (sub)domain with an A or AAAA record. You cannot chain several CNAME records together.
Finding Service Addresses
If you want to use a CNAME record to simplify access to various VEDOS services, use this guide:
- FTP: You can find the FTP server address for Webhosting according to the instructions FTP – Login.
- SMTP, POP/IMAP: You can find the mailserver addresses according to the instructions E-mails – SMTP, POP3, IMAP.
You can find an example of use in the section Examples of CNAME Records.
If the service whose address you want to find is not with VEDOS, look up the service’s help documentation or contact its provider’s support.
Entering CNAME Records
A general guide to setting up DNS records in the customer administration can be found in the article DNS – Domain Records.
If the domain uses different DNS servers, changes to VEDOS records will not affect its behavior.
A CNAME record must be a subdomain. The name field must therefore contain either the * character or the name of a specific subdomain; it cannot be empty.
In the data field, enter the name of the domain or subdomain that the subdomain should mask. Omit the protocol (http, https) from the name. Do not enter IP addresses in the data field either; those are entered using A and AAAA records.
Name TTL Type Data (* character, or subdomain) 300 CNAME (domain or subdomain name)
Examples of CNAME Records
Example: Webhosting FTP server as subdomain ftp.domena.tld:
Example: POP, IMAP, and SMTP servers as the pop, imap, and smtp subdomains:
Example: Pointing the www subdomain and all its subdomains (*.www) to the external service www.wds-test.cz.
DNAME Record Type
VEDOS supports DNAME records only for subdomains.
DNAME records work similarly to CNAME, but instead of a single specific subdomain, they point all lower-level domains relative to the given subdomain (except the selected subdomain itself). In this redirection, they preserve the structure of these lower-level subdomains relative to the target subdomain.
The other differences compared to CNAME are:
- It does not apply to the specified subdomain, only to all of its subdomains, whereas CNAME works only for the specified subdomain and nothing else.
- They allow other records to be entered for the given subdomain, whereas CNAME is incompatible with any other record (including DNAME) for the given subdomain.
Common Problems
Common problems with ALIAS, CNAME, and DNAME records include:
ALIAS Record Cannot Be Created
Problem: An error appears when trying to create the record.
Cause: An ALIAS record conflicts with another existing record, or you are entering it as a subdomain.
Solution: Verify that:
- You are entering the record without a name.
- There is no A, AAAA, or ALIAS record without a name in the DNS records. If you find such a record, delete it.
Cannot Create a Subdomain Record
Problem: An error is displayed saying that the new record cannot be created because a CNAME record already exists for the subdomain.
Cause: If a CNAME record exists for a subdomain, you cannot create a record of another type for it, and vice versa, you cannot create a CNAME for a subdomain with an existing record of another type.
Solution: Delete the conflicting records.
Frequently Asked Questions
Can I enter an ALIAS record for a subdomain?
Not currently. Use a CNAME record.
My old hosting had a CNAME record named www with data www.provider.tld. How do I change this record so that it points to hosting at VEDOS?
VEDOS does not use this type of routing. Delete the record and replace it with an A record with the name * and data corresponding to the IP address of your Webhosting.
What if I have a CNAME record named * and want to add a subdomain shop with another CNAME or another record type?
A record named * applies only to subdomains that do not have another DNS record. So you can add the shop subdomain without any problem with any record type, including CNAME.