We've successfully setup Mailflow for our MS365 domain. We used the "copy existing MS365 Domains and Policies" and confirmed.
Mailflow seems to be working correctly after testing. All looking good. However I am curious what to do with the existing DNS settings that we've configured at our 3rd party DNS hosting for the old situation.
What happens to existing created records that are still pointing to the SOphos Hydra servers?
- MX
- SPF
DO these servers need to be removed and MX reverted back to the initlal MS365 DNS from Microsoft?
I have a hard time finding out if anything in DNS config is neccesary to revert or not.
DNS MX records should all point to M365 and SPF should be updated as well to v=spf1 include:spf.protection.outlook.com -all and of course any other records you need in your specific SPF record.
Another thing i have noticed are the "old" connectors in Exchange admin Center which were created during initial old style Sophos Email setup with the gateway configured.
I'm not sure this was in de documentation but they should be disabled and/or removed i would say:
Correct we can't automatically remove them because it could potentially break something for other domains that may not have moved to MFR yet. I see you have them turn off so outside of being visible there is no harm in leaving them there for a time period.