DNS check does a basic A record query for example.domain.com. Nothing fancy.
Perhaps your DNS server blocks queries like that?
54 2.087774 10.193.67.237 10.193.67.236 DNS 78 Standard query 0x96b2 A example.ntap.local
55 2.088023 10.193.67.236 10.193.67.237 DNS 142 Standard query response 0x96b2 No such name A example.ntap.local SOA oneway.ntap.local
::*> dns check -vserver DEMO
Name Server
Vserver Name Server Status Status Details
------------- --------------- ------------ --------------------------
DEMO x.x.x.x up Response time (msec): 46