I need to put in DNS record rDNS (wich PTR record) because GMAIL reject mail of domain hosted in my server. In the manual's IspConfig 3 I can read how to PTR records for a domain, but I have some questions: I have some domains in the same server. I have DNS record in production in this moment, and in Zone (SOA) I have example.com. In the example's manual in Zone (SOA) 3.2.1.in-addr.arpa. I need create a new record Zone (SOA) or rewrite the old record example.com. for x.y.z.in-addr.arpa. Thanks for all.