Re: MTA (corrected)

[Vincent Lefevre <vincent@vinc17.net>]

On 2021-07-05 10:32:27 -0400, Polyna-Maude Racicot-Summerside wrote:
> > What is this 162.213.253.79 IP address?
> 
> The IP address 162.213.253.79 is the dedicated IP I rent from Namecheap.

OK.

>  Can you control its reverse?
> >
> Good question, I'll need to go back read a bit on networking and DNS
> management.
> > Is cyrania.com a domain that you own?
> Yes, I own cyrania.com and polynamaude.com (the domain name used for the
> email I am sending). I know the SMTP server respond to the name
> CYRANIA.COM (HELO) but is relaying mail for polynamaude.com too.

It seems that you already set up the reverse for 162.213.253.79 since
it is cyrania.com (your domain).

You may want to add 162.213.253.79 to the cyrania.com IP addresses,
but if cyrania.com is used as a www host and 162.213.253.79 shoud
not be used for this purpose, this is not OK.

In general, it is better to have a specific FQDN for each IP address.
For instance, 162.213.253.79 would have nodename.cyrania.com as the
reverse and nodename.cyrania.com would resolve to 162.213.253.79,
where nodename is the name obtained with the "uname -n" command.

-- 
Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)