PMG default DNS configuration

[rg2]

Hi,

I'm using PMG for almost a year now. I'm using PMG for incoming and outgoing e-mails for several domains I manage.

Since I first insalled PMG on a test environment over a year ago, I never changed the default DNS configuration on the PMG interface:

Configuration -> DNS

Search Domain: vcn.vcnoracle.com
DNS Server 1: 169.254.169.254

As you have probably guessed, I run my VMs on OCI (Oracle Cloud Infrastructure).

I never changed this configuration because I never needed. I can receive and send e-mails without any problems... but today I got the first case which I believe is related to this configuration.

My server could not deliver a message to an external domain. The error message that was returning is:

said: 554 5.7.1 This message has been blocked because the HELO/EHLO domain is invalid. (in reply to MAIL FROM command)

My HELO message is this:

220-antispam-mx1.vcn.oraclevcn.com mx1.[edited].net

Where:
"antispam-mx1" is the hostname of the VM.
"vcn.oraclevcn.com" is the Search Domain
"mx1.[edited].net" is the actual name of the server, where the PTR (reverse IP) is configured

All tests on mxtoolbox.com are all valid, not a single error... but I find it strange that all Mail Delivery System e-mails come from:

Mail Delivery System <MAILER-DAEMON@antispam-mx1.vcn.oraclevcn.com>

And all Daily Spam reports come from:

Antispam@antispam-mx1.vcn.oraclevcn.com

What should I change so both the HELO message and the sender of Mail Delivery System and Daily Spam Reports are "mx1.[edited].net"?

Thanks

 

[Stoiko Ivanov]

see: https://pmg.proxmox.com/pmg-docs/pmg-admin-guide.html#_configuration_files_overview
the fqdn (which is used in most situations) is composed of the hostname (/etc/hostname) and the search domain in /etc/resolv.conf

if possible simply configure them correctly
if not you can modify the appropriate sections of the postfix config following:
https://pmg.proxmox.com/pmg-docs/pmg-admin-guide.html#pmgconfig_template_engine

I hope this helps!

 

[rg2]

see: https://pmg.proxmox.com/pmg-docs/pmg-admin-guide.html#_configuration_files_overview
the fqdn (which is used in most situations) is composed of the hostname (/etc/hostname) and the search domain in /etc/resolv.conf

if possible simply configure them correctly
if not you can modify the appropriate sections of the postfix config following:
https://pmg.proxmox.com/pmg-docs/pmg-admin-guide.html#pmgconfig_template_engine

I hope this helps!

Thank you for the information!

Can I safely change both configuration (hostname and search domain) on the production environment? Could this change break something?