Peplink Balance 580 DNS: Cannot Ping Root Domain

I have a Balance 580 hosting multiple domains. The integrated DNS works fine, except I have one problem. From the outside, I cannot ping any of the root domains (other than the SOA domain). For example, I can ping “www.domain.com”, but cannot ping “domain.com.” I even tried to create an “A” record called * to define a wildcard with no sucess. What do I need to do in the DNS of each domain record in order to get this to work? Everything on the inside (server side) is correctly configured. I know for sure that the 580’s DNS server is causing this, as my old load balancer and other domains that use external DNS servers with the sites that I am hosting ping just fine at each domain’s root level. Please help.

I figured out my own question, but wanted to post the solution if others were having the same issue.
I simply created a blank A record for each domain, and then it added an entry for domain,com.