Hello, i have my server working now, i can send and receive email, i have 2 diferents domains working for the tests (i need to add like 20 domains for the production stage), a web with database, everything works fine with the exception that the DNS i set in the zone for one of those domains are not refreshing. hostbaires.net is also the same name of my server, the DNS of this one works fine. istorepos.com.mx is the one that the DNS are not refreshing. I've got it running on Debian 9, i've use the perfect-server-debian-9-stretch-apache-bind-dovecot-ispconfig-3 For istorepos.com.mx in the zone i've got a dmarc record with the following values: Code: v=DMARC1;p=quarantine;sp=quarantine;pct=100;adkim=r;aspf=r;rua=mailto:[email protected];ruf=mailto:[email protected];rf=afrf;ri=86400;fo=0 But if i use different tools to check the dmarc record i've got the original values of the first one i crate for tests: Code: v=DMARC1;p=none;sp=none;pct=100;adkim=r;aspf=r;rua=mailto:[email protected];rf=afrf;ri=86400;fo=1 Also i set a reverse zone for my server, following this tutorial: https://www.howtoforge.com/tutorial...vice-with-ispconfig/#nbspreverse-name-service But in some tools on the web i've got a warning message for both of my domains. smtp mail.hostbaires.net Reverse DNS is not a valid Hostname smtp mail.istorepos.com.mx Reverse DNS is not a valid Hostname I'm brand new in this matters, and i'm sure i've done a lot of things wrong, so if you can point me in the right direction i will appreciate a lot the help, also if you need the informations of some logs please tell me.