Relating to this option: https://www.directadmin.com/features.php?id=1904 it only works if the top level domain is local. This changes is not needed if the local parent zone copy is to be pushed remotely, which MSS already handles. If the parent zone is on a remote MSS server, but not locally (one-way MSS dns), the MSS would need to push the DS records to the remote box. new internal default: dnssec_add_subdomain_ds_to_remote_parent=1 which applies when DA cannot find any local parent, and there are 2 or more periods in the current zone name (as it could be a subdomain). This can potentially slow down dns writes if it's a subdomain zone and dnssec + MSS is enabled, so we've provided the option to shut it off, if you know all parent zones are local. The subdomain server, connects to CMD_API_DNS_ADMIN with the following request: action=add cluster=yes subdomain=sub.domain.com overwrite=yes type=DS name=sub.domain.com. values0=SUBDS1 values1=SUBDS2 where, this combination of strings tells the remote box (that received the request) to try and figure out which zone subdomain belongs to. If it cannot find the parent zone, it's not an error (error=0), but paren_exists=no is returned. T6787,T12614