Score:0

SPF records with a dynamic IP to a smtp relay with Office 365

mx flag

I'm helping out a client setup an smtp relay because our software is failing at times to send email when using the smtp server of smtp.office365.com and we have found that setting up a smtp relay via this link option 3 https://docs.microsoft.com/en-us/exchange/mail-flow-best-practices/how-to-set-up-a-multifunction-device-or-application-to-send-email-using-microsoft-365-or-office-365 resolves this problem.

This client though does not have a static IP at there location so they setup a ddns.net address to resolve that but the SPF record part were having a hard time understanding what it should look like.

Here currently what we think it should look like based on reading on SPF records and the a option.

v=spf1 a:clientname.ddns.net include:spf.protection.outlook.com ~all

Is this right or do we need them to to get a static IP to get this to work?

jp flag
It is always preferable to get a static IP to send emails because dynamic IPs are frequently included in blocklists.
mangohost

Post an answer

Most people don’t grasp that asking a lot of questions unlocks learning and improves interpersonal bonding. In Alison’s studies, for example, though people could accurately recall how many questions had been asked in their conversations, they didn’t intuit the link between questions and liking. Across four studies, in which participants were engaged in conversations themselves or read transcripts of others’ conversations, people tended not to realize that question asking would influence—or had influenced—the level of amity between the conversationalists.