- Plesk for Linux
- Plesk for Windows
Note: This article has the reference to the issue with the fix available:
- #PPPM-4301 "Fixed the issue where users could not use the underscore character (_) in domain names and CNAME DNS records."
- Plesk Onyx 17.5.3 Update 46 23 April 2018
Unable to create a DNS record with the underscore symbol "_". The following error appears in Plesk:
PLESK_ERROR: The specified domain name is not valid. You need to specify a valid domain name like domain.com.
Plesk bug with ID #PPPM-4301.
According to RFC 2872, underscores are used to disambiguate hosts from other attributes in the DNS. Underscores are not allowed in the hostname itself.
Until the bug is resolved, as a workaround, create a DNS record via command line:
2. Run the following command:
CONFIG_TEXT: plesk bin dns --add example.com -cname _sample -canonical example.org
Replace example.com with the appropriate domain name.
After doing that this record will appear in Domains > example.com > DNS Settings