I have domain example.company.com which is DNSSEC secured and has sent its DS records to the parent company.com. I want to create 2 other subdomains, both DNSSEC secured, sub1.example.company.com and sub2.example.company.com. However the parent domain here is example.company.com and not company.com so I want to include the DS records for the subdomains in the zone file for example.company.com.
However when I add the DS records manually and try to resign example.company.com using the same keys as before (unexpired) I get the following error
dnssec-signzone: fatal: dnssec-signzone: fatal: 'sub1.example.company.com': found DS RRset without NS RRset
What am I doing wrong here, alternatively how can I ensure DNSSEC protection from my subdomains given my existing main domain (example.company.com)?