Is it possible in DNS to redirect to different servers depending on the port?

Question

Domain Name System

Specific task: to transfer boxes and their users as quickly and painlessly as possible from, God forgive me, nic.ru , to, say, pdd.yandex.ru .
The problem is this: Nick uses the same server name under pop, imap, smtp - mail.nic.ru , while PDD uses imap.yandex.ru , smtp.yandex.ru . Ports, respectively, are the same here and there.
In a situation with “separate” names, my cunning face would simply register CNAME ( imap.nic.ru » imap.yandex.ru ) on the local DNS server, and then slowly reconfigure users.
But how to make mail.nic.ru:995 go to pop.yandex.ru:995, and mail.nic.ru:465 to smtp.yandex.ru:465 .
Or is my approach fundamentally wrong? In this case, please poke your nose where you need it.

Answer 1

DNS knows nothing about ports. More precisely, in theory, there is an SRV-record, but it is not at all for that, and in practice it is not used and is not supported by anything.
In this case, you need to raise NAT

Answer 2

The topic is old, I suffer from necrophilia. Given that no one has answered for 2 years ...
If you manage to transfer user boxes (as the previous speaker talked about) to a new server, it will be enough to bind mail.nic.ru to pop.yandex.ru on the local DNS server. To do this, you declare the nic.ru materzone, transfer records from the real zone to it, except for mail, and for mail you make CNAME to pop.yandex.ru.
Instead of pop.yandex.ru, you can use smtp.yandex.ru - their addresses are the same.

Answer 3

Are the server names, accounts, user passwords the same? How will the authorization on the server go if you forcibly direct traffic to another server?
IMHO - no way. Only reconfiguring accounts at workplaces