Last week we looked at why it is essential to have SPF and DKIM validations in place. For a long time these validations were just another way to improve the deliverability of your emails, until they became essential and fundamental to any email marketing strategy. The thing is that spammers' strategies were also updated and they found a way to use these validations to their advantage. At the same time, SPF and DKIM are far from being universally implemented and even worse if we are talking about standardised processes. That is why DMARC was born.
DMARC is basically a new standard that aims to unify the current validations. DMARC does not come to replace these validations, it is simply a way to unify how they are published and, mainly, what ISPs like Gmail or Outlook should do if they receive an email that fails validation.
DMARC.org official website
By implementing it, they can tell ISPs what to do with emails that fail validation or are not properly configured. They can choose to be strict (looking for all validations and settings to be correct in order to let it through) or "relaxed" (literally "relaxed", where they look for at least some validation only to let it through). As an added benefit, Gmail and Outlook will send you a report of emails that are causing problems so you can identify whether they are phishing or just misconfiguration.
While the benefits are huge, you should keep in mind that in order to implement DMARC, it is very important to have the domains you use for email marketing well configured and under full control. After all, if you implement this and you don't have SPF or DKIM, or one of the domains you use in your mailings (for example: one that you use only for last minute promotions and no one was aware of) is not in the registry, you run the risk of telling ISPs to block your own emails.
That's why it's important to know what you need to be aware of before you implement it and then how to implement it.
Before you start
We need to check and identify:
All the domains we use to send our mailings. DMARC checks that the domain that appears in the FROM of your emails is the same as the one in your SPF and DKIM records, so if we forget any of them, they will be blocked as suspicious.
Once identified we must ensure that all these domains are aligned (SPF, DKIM and FROM).
Have one or more email boxes ready to receive the reports that ISPs will start sending us. Keep in mind that this can be a large volume of incoming emails, so it is not recommended that you use your personal mailbox. Ideally you should have a mailbox specifically for this, for example: [email protected]
How to implement it
Implementing DMARC is fairly straightforward thankfully, and if you have SPF or DKIM in place, it means you have the necessary DNS access and settings to do this as well (in fact, make a place in your diary this week to do this). When creating the registry you only need to take into account these values:
v= is the name of the record, for example "DMARC1".
p= this is where we say what we want to do with our emails. It can be: reject, quarantine or none.
rua/ruf= is the form in which they request that you send them reports of detected bugs. "rua" is used when you want a more general summary or report, "ruf" is used if you want to receive the full messages that have failed. To use the latter, make sure you use a mailbox that can handle the incoming mail this may generate.
So, an example DMARC record would be:
"v=DMARC1; p=none; rua=mailto:[email protected]"
At first it is good to use "p=none". This way we can start by just monitoring and discovering any errors that the registry or our validations may have. Once we are sure that everything is OK, we can change it to "p=quarantine".
In the name field of your DNS manager, just type "_dmarc.yourdomain.com". In some cases, you only need to type "_dmarc" because the domain is already bound to the TXT record.
If you have the necessary knowledge and access, log into your DNS zone and create your DMARC. If you are not sure where to start, just let us know and we will guide you step by step!
