Sending mail and 2 channels to the Internet

Question

Email

There is a mail server, there is a gateway, there is a channel to the Internet, there is a domain.
External ip on the gateway 1.1.1.1
Firma.ru domain

A-record in dns by firma.rf returns 1.1.1.1 Recordback
by 1.1.1.1 returns firma.ru
MX-record for firma.ru is firma.ru itself
Everything is just logical and understandable. But I want reliability in the form of a second channel on the Internet. Yes, and using 2 channels you can get more speed.

In my vision, it will be necessary to do this:

Make A-records:
mx1.firma.ru 1.1.1.1
mx2.firma.ru 2.2.2.2,

respectively, make MX-records for firma.ru.

But what about sending emails? If you make the same writeback for the second IP as for the first one, won't any anti-spam swear at it?

Answer 1

google spf record multiple ip

Answer 2

I have 2 channels, they are resolved on the same Frey gateway, the name in the MX is the same, it is also indicated for the wires in the PTR.
In DNSe 2 And records for this name.
There were no problems with antispam.

Answer 3

and reverse records for both ip where specify? on mx1/2.firma.ru or whatever?
1 antispam check is usually a reverse resolve check - if the server is mx.firma.ru -> 1.1.1.1 then the opposite should be true, i.e. 1.1.1.1 should be mx.firma,ru, not 234wrf.client.host.provider .com
further any dkim/spf.
which, however, does not prevent your IP from getting into spam lists and sending your letters to null precisely because the administrator considered that the spam list “such and such” is cooler than dns / dkim / spf in priority

Answer 4

Leave reverses for both IPs on firma.ru (or any other canonical name like server.firma.ru) and make two A-records for the canonical name on both IPs. In HELO, say the canonical name. For MXs, make separate A-records with MX - this does not contradict anything.
Those. it is necessary that:
1. There must be a PTR record
2. In the list of addresses received during the reverse resolution of this record, there was an address from which the connection came
3. It is desirable that it is also present in
HELO checks.