Topic: setting iRedMail as backup MTA?
can iRedMail be setup as backup MTA for primary iRedMail?
backup server should only receive e-mails to queue (there are no mailboxes on backup MTA) and relay it to master server (for purpose of master server maintenance, upgrade and similar). Postfix can be setup in that way, but there is difference in Anti SPAM settings so backup server wouldn't be abused and used as spam relay.
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