How to set SPF correctly?

Question

SPF

tell me how to set up SPF correctly on servers.
script MailWizz host vds/vesta / centoc
script offers such a construction for verification, mai-tester does not always accept it.
mrcstudio.ru TXT v=spf1 mx a ptr a:smtp.fire-ip.ru a:bizmy-mails.ru ip4:212.86.102.53 ip4:78.108.82.225 ~all
parsing:
- fire-ip.ru - costs operating system / vds
- bizmy-mails.ru ip4:212.86.102.53 - there is the mailing script itself
- ip4:78.108.82.225 - the main vds address on which the smtp domain from which it sends is located.
As it is not so confusing - do not you think? Please tell me how to correct it..

Answer 1

tester dkim.zxcat.ru/spf.html
gave such an error
The ptr mechanism is outdated, it is not recommended to use
the rest says - correctly

Answer 2

We should try to minimize the number of name resolutions, because firstly, this process is not reliable and there is a potential for failure on any resolution, and secondly, the standard limits 10 name resolutions per policy.
Therefore, you should not use AND "a" AND "mx", because they look at the same host, with mx in your case requiring 2 name resolutions, you don't need "ptr" at all (and it also requires two or more name resolutions), for the rest of the records, if you have static addresses by agreement - it's better to use in the SPF record ip4, not "a".