I would like to allow my home nas server to send notification mail to my phone and for this reason I need to configure a smarthost mail server. I already have a mailcow server running on a OVH server, so I thought I could use that. I configured my nas to use the mailcow server, and I added my home IP address to mailcow under forwarding hosts, but when I try to send mail it seems the host is rejecting it.
2022-07-02 22:06:44 1o7jO8-0023ud-1m ** my.real.email@gmail <firstname.lastname@example.org> R=smarthost T=remote_smtp_smarthost H=mail.server.name [178.32.xx.xx] X=TLS1.3:ECDHE_SECP256R1__ECDSA_SECP384R1_SHA384__AES_256_GCM:256 CV=yes DN="CN=mail.server.name": SMTP error from remote mail server after RCPT TO:<my.real.email@gmail >: 554 5.7.1 <94-225-xx-xx.access.my.isp[94.225.xx.xx]>: Client host rejected: Access denied
I would have thought this is a pretty common setup but I can’t find any documentation explaining how to set it up in mailcow. If anyone could point me in the right direction it would be most appreciated.