This article discusses in detail DNS records of the ALIAS, CNAME and DNAME types. For a general guide to DNS records and how to set them up in the customer administration, see DNS - Domain Records.
In this article you will read:
- 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 an ANAME) is used to point the main domain to an existing domain or subdomain. Some hosting providers prefer this type of record over A and AAAA records.
If you need to point your own subdomain to a provider domain or subdomain, use a CNAME record.
The ALIAS record works only on primary DNS servers. When a record is created, the system automatically looks up the currently set A/AAAA records for the ALIAS value (if any) and inserts them into DNS. The update is handled by automatic synchronization, so the timeliness of the records depends on the TTL of the ALIAS and the TTL of the relevant records on the source domain (or other domains in the chain) and other circumstances.
We do not guarantee the synchronization time of A/AAAA records against ALIAS.
Entering ALIAS records
For general instructions on setting up DNS records in the customer administration, see DNS - Domain Records.
If the domain uses other DNS servers, changes to VEDOS records will not affect its behavior.
The ALIAS record must be a master domain. Therefore, the name field must be empty.
In the data field, enter the name of the domain or subdomain that you want the main domain to overlay. Omit the protocol (http, https) from the name. Do not enter IP addresses in the data field either, these are entered using A and AAAA records.
Name TTL Type Data
(leave blank) 300 ALIAS (domain or subdomain name)
Example of an ALIAS record type
Example: a (realistically broken) ALIAS record for default.wedos.net.
CNAME type record
CNAME records are used to point a subdomain to an existing domain or subdomain. The most common uses include routing subdomains to web hosts that require or support this type of routing, or to services such as FTP, SMTP, POP/IMAP.
Because CNAME effectively turns one subdomain into another (sub)domain, you cannot create records of a different type for a subdomain that has a CNAME record, and vice versa.
The CNAME record must also point to a (sub)domain with a type A or AAAA record. Multiple CNAME records cannot be chained in sequence.
Finding service addresses
To use a CNAME record to simplify access to the various VEDOS services, use this signpost:
- FTP: You can find the address of the FTP server of the Webhosting by following the instructions FTP - Login.
- SMTP, POP/IMAP: You can find the addresses of the mailservers by following the instructions Emails - SMTP, POP3, IMAP.
For a sample use case, see Examples of CNAME records.
If the service whose address you want to find out is not available from VEDOS, search for the help for that service or contact the support of its provider.
Entering CNAME records
For general instructions on setting up DNS records in the customer administration, see DNS - Domain Records.
If the domain uses other DNS servers, changes to VEDOS records will not affect its behavior.
The CNAME record must be a subdomain. Therefore, the name field must contain a * 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 is to overlay. Omit the protocol (http, https) from the name. Do not enter IP addresses in the data field either, these 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 a subdomain ftp.domena.tld:
Example: POP, IMAP and SMTP servers as subdomains of pop, imap and smtp:
Example: pointing the subdomain www and all its subdomains (*.www) to the external service www.wds-test.cz.
DNAME record type
DNAME entries work similarly to CNAMEs, instead of one specific (sub)domain, they route all subdomains of the domain (except the selected domain itself). In this redirection, they preserve the structure of these subdomains relative to the target domain.
Other differences from CNAME are:
- They can also be specified on the main domain, while CNAME works only for subdomains.
- It is not valid for the specified domain, only for all its subdomains, while CNAME works only for the specified subdomain and nothing else.
- They allow you to specify other records for a given (sub)domain, while CNAME is incompatible with any other record (including DNAME) for a given subdomain.
If you need to point all subdomains of one domain to the corresponding subdomains of another domain, the CNAME solution looks like this:
Name TTL Type Data
subdomain1 300 CNAME subdomain1.nova-domain.tld
subdomain2 300 CNAME subdomain2.nova-domain.tld
and so on - for each subdomain you must create a corresponding CNAME record.
When using DNAME, to get the same result for any number of subdomains, just specify:
Name TTL Type Data
300 DNAME nova-domain.tld
The DNAME record used in this way does not affect the main domain in any way, but directs all its subdomains to the corresponding subdomains .nova-domena.tld.
Common problems
Common problems with ALIAS, CNAME and DNAME records include:
The ALIAS record cannot be created
Problem: An error is displayed when trying to create a record.
Cause: the ALIAS record conflicts with another existing record, or you are entering it as a subdomain.
Solution: Verify that:
- You enter the record without a name.
- There is no unnamed A, AAAA, or ALIAS record in DNS records. If you find such a record, delete it.
Cannot create a subdomain record
Problem: An error is displayed stating that a 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 conversely, 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 specify an ALIAS record for a subdomain?
You can't at the moment. Use a CNAME record.
My old hosting had a CNAME record with the name www and the data www.poskytovatel.tld. How do I change this record to point to VEDOS hosting?
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 Webhost.
What if I have a CNAME record named * and I want to add a subdomain store with a different CNAME or a different record type?
A record named * applies only to subdomains that do not have another DNS record. So you can easily add a subdomain store with any record type, including CNAME.