owner {ttl} addr RP mbox_domain_name TXT_domain_name
franklin IN RP franklin.berkeley.edu admin.berkeley.edu.
The Responsible Person record, RP, identifies the name or group name of the responsible person for a host. Often it is desirable to be able to identify the responsible entity for a particular host. Otherwise, when that host is down or malfunctioning, it is difficult to contact someone who can resolve the problem or repair the host.The mbox domain name field is a domain name that specifies the mailbox for the responsible person. Its format in master files uses the DNS convention for mailbox encoding, identical to that used for the Person-in-charge mailbox field in the SOA record. In the example given here, the mbox domain name shows the encoding for ben@franklin.berkeley.edu. You can specify the root domain name (just ".") to indicate that no mailbox is available.
The last field is a domain name for which TXT RRs exist. You can perform a subsequent query to retrieve the associated TXT resource records at the TXT domain name. Retrieving the TXT records provides a level of indirection so that the entity can be referred to from multiple places in the DNS. You can specify the root domain name (just ".") for the TXT domain name to indicate that no associated TXT RR exists. In the example, "sysadmins.berkeley.edu." is the name of a TXT record that could contain some text with names and phone numbers.
The format of the RP record is class insensitive. Multiple RP records at a single name may be present in the database. They should have identical TTLs.
The RP record is experimental; not all DNS servers implement or recognize it.