Is it possible to change IP address for outgoing mail in Postfix without changing MX records?

Question

Is it possible to change IP address for outgoing mail in Postfix without changing MX records?

Answer

When in Tools & Settings > Mail Server Settings the option Outgoing mail mode is set to Send from the specified IP addresses , MX records are updated along with the Postfix configuration because of SPF.

If just change
smtp_bind_address
parameter in the
/etc/postfix/main.cf
file, but MX records contain the old IP address, there will be difficulties with the outgoing mail delivery from a Plesk server – SPF check will be failed on the receiving end due to different IP addresses in the MX and SPF records.

The
smtp_bind_address
parameter can be changed manually in the
/etc/postfix/main.cf
file, but at your own risk – this change will be rewritten by Plesk when changing Tools & Settings > Mail Server Settings > Outgoing mail mode , and the difficulties mentioned above will occur.