**To check the availability of a CNAME**
The following command checks the availability of the subdomain ``my-cname.elasticbeanstalk.com``::
aws elasticbeanstalk check-dns-availability --cname-prefix my-cname
Output::
{
"Available": true,
"FullyQualifiedCNAME": "my-cname.elasticbeanstalk.com"
}