Apologies if this has been asked before, in my defence I’m a total newbie to this forum.
Whilst I understand the need for domain authentication (spf, dkim, dmarc) to help ensure email deliverability from domains that reside on a host I am a little unclear as to whether the host machine also requires host name authentication ie spf, dkim, dmarc.
So, my question - Do I need to add SPF, DKIM, DMARC records for the machine’s FQDN as well?
All advice greatly received 
SPK/DKIM/DMARC are all optional, but only needed in instances where the domain in question is sending email.
If the server isn’t sending/forwarding email from the default domain (like user@example.vs.mythic-beasts.com), then there’s no need to do that, but you should make sure you have reverse DNS set for the IP address that points somewhere, ideally pointing back to the servers FQDN, especially on IPv6 as Google require a v6 address to have RDNS to accept mail from it.
Response from Paul at MB. I’ve included this response because I hadn’t ever realised the importance of adding the server host’s name to spf records for domains being hosted. Every day’s a school day!
'SPF, DKIM and DMARC records all relate to a domain that you want to be able to send email from.
The SPF record for your domain needs to list the servers (hosts) that will send mail from your domain.
DKIM records provide the public part of the keys that are used to sign emails sent from your domain. You will need to include keys for any service that is signing your outgoing emails.
The DMARC record declares the policy for your domain, telling recipients what they should do with received emails that do not pass authentication.’
regards Paul
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Thanks Paul