nameserver.localdomain - How to change it?

@aaPanel_Kern I'd like to fix it too as my mailserver isn't sending mails to @Yahoo.com

Hello, please check the posfix configuration file and check what the host name is.

aaP_admin197
aaPanel_Kern postfix configuration file says:

myhostname = localhost.localdomain

I'm using cloudflare, can I change it to my domain mail.domain.com?

aaP_imhd3d
Yes, after modification, you need to restart posfix