4.1.1 Master Zone Type

User can configure the SOA (start of authority) record if the zone type is Master. The Start of Authority record announces important authoritative information about a namespace to the name server. In Zone file, there is one NS and A record created.

For SOA record, user has to configure the parameters in the following table.

Table 4-2 Master Zone Type

Parameter Name	Description
SOA Domain Name	Primary master name server for this zone.
SOA Mail Id	Email address of the administrator responsible for this zone.
SOA IP Address	IP address for the first A record.
SOA Refresh	Number of seconds after which secondary name servers should query the master for the SOA record, to detect zone changes.
SOA Retry	Number of seconds after which secondary name servers should retry to request the serial number from the master if the master does not respond.
SOA Expire	Number of seconds after which secondary name servers should stop answering request for this zone if the master does not respond.
SOA TTL	The default time-to-live field determines the TTL of records in the zone that do not have one set explicitly.

Once user configures the DNS zone then zone file is created. User can add new DNS records in this zone file using "DNS Record Configuration" MO.

Snapshot for ZoneFile

$ORIGIN demo.com.
$TTL 32767
@       SOA     hostname.      hostnamemail. (
                1
                32767
                32767
                32767
                32767 )


        NS      hostname
hostname        A       10.23.2.178

If ENUM MP restarts and there is no change in configuration for this zone, then this zone file is not deleted. The serial number of this zone file is stored in Internal table.

If there is no change in serial number in zone file already present, then on restart of ENUM MP, this file is not deleted. If there is change in serial number then this zone file is deleted on MP and a new zone file is created with updated DNS records.