Definitions for "Primary Server"
The name server that will be used first and will be relied upon before any of the other name servers that may be listed when a domain name is registered with the registry. When registering names with the Registry, registrars must provide the name and IP address of a primary server for the name.
Another name for a stratum 1 server. See also ``stratum''.
When applying for a domain name, a registrant must provide the hostname and Internet Protocol (IP) number of the name server that will both contain authoritative data for the name being registered and resolve that domain name to the appropriate IP number. The Primary server is the one that is used first, and the Secondary server is the 'backup' server used if the Primary server does not respond.
Keywords:  twin, tailed, node, disk, maintains
When physical disks are connected to two nodes (twin-tailed), this is the node that normally maintains and controls local access to the disk.