Email remains one of the most important communication tools for businesses, but it is also one of the easiest channels for criminals to abuse.
One of the most common threats is email spoofing, where someone sends an email that appears to come from your domain even though it was never sent by you or your mail server. These emails can be used for phishing, fraudulent invoices, password theft and other scams.
This is where DMARC becomes important.
For a practical example, read our email spoofing case study, which explains how an altered invoice can be used to impersonate a business.
What is DMARC?
DMARC stands for Domain-based Message Authentication, Reporting and Conformance.
It works alongside two other important email authentication technologies, SPF and DKIM, to help receiving mail servers determine whether an email claiming to come from your domain is legitimate.
A DMARC record is published in the DNS records for your domain and provides instructions to receiving mail servers about what they should do when an email fails authentication.
Depending on how DMARC is configured, those instructions can range from simply monitoring suspicious messages to quarantining them or rejecting them completely.
The Danger of Not Having DMARC
Without DMARC, criminals may be able to impersonate your domain when sending fraudulent emails.
For example, a criminal could potentially send an email appearing to come from:
accounts@yourcompany.co.za
The email might instruct a customer to pay an invoice into a different bank account or ask an employee to provide confidential information.
Even though the email was never sent through your mail server, the recipient may believe it came from your company because your domain appears in the sender address.
The consequences can extend well beyond a single fraudulent email.
Your customers could lose money. Your business reputation could be damaged. Your domain could develop a poor sending reputation, and legitimate emails may increasingly be treated as spam.
There is also a significant difference between discovering that somebody is abusing your domain and actually being able to see where those emails are coming from.
DMARC reporting helps provide that visibility.
Simply Having a DMARC Record Is Not Enough
This is an important distinction.
At Rhino Hosting, we can implement a basic DMARC record as part of our hosting packages at no additional charge.
However, simply having a DMARC record does not automatically mean your domain is protected.
Many domains initially use a DMARC policy known as:
p=none
This effectively tells receiving mail servers:
“Monitor what is happening and send reports, but do not block anything yet.”
This is an important first step because immediately setting DMARC to reject unauthorised email without first understanding how your organisation sends mail can cause legitimate messages to be rejected.
Businesses frequently send email through more systems than they realise.
Your normal mail server may only be one of them.
Your website, contact forms, accounting system, CRM, newsletter service, support system, Microsoft 365, Google Workspace or other third-party platforms may all legitimately send email using your domain.
If DMARC is hardened before these services are identified and correctly configured, legitimate email could stop being delivered.
DMARC Needs to Be Monitored Before It Is Hardened
The safest approach is therefore to introduce DMARC gradually.
Rhino Hosting offers a managed DMARC monitoring service where we analyse the reports generated by your domain and identify which servers and services are sending email on your behalf.
During the first six months, we monitor the domain and review the DMARC reports to establish what legitimate email activity looks like.
Where required, we can also make changes to your SPF configuration so that legitimate services are correctly authorised.
You receive weekly reports during this initial six-month monitoring period, allowing you to see what is happening with email claiming to originate from your domain.
Once we have built a reliable picture of your legitimate email sources, we can progressively harden the DMARC policy.
The ultimate goal is to move away from monitoring-only policies and towards stronger enforcement, including quarantine or reject, where appropriate.
A properly configured p=reject policy tells participating receiving mail servers to reject messages that claim to come from your domain but fail the required DMARC authentication checks.
This provides significantly stronger protection against criminals directly spoofing your domain.
Rhino Hosting Managed DMARC Service
The managed service costs R600 per month for the first six months.
During this period, Rhino Hosting will monitor DMARC activity, analyse mail sources, provide weekly reports and assist with necessary SPF changes as legitimate sending services are identified.
After the initial six-month monitoring and implementation period, the service reduces to R100 per month, which includes ongoing monitoring and a monthly DMARC report.
Email systems change over time. New services are introduced, websites are replaced, accounting platforms change and employees may start using new systems.
For this reason, DMARC should not simply be configured once and forgotten.
Ongoing monitoring helps ensure that your email authentication remains correctly configured while also providing visibility into attempts to misuse your domain.
Protect More Than Your Inbox
DMARC is not simply about reducing spam.
It is about protecting your domain, your business reputation and the people who trust emails carrying your company name.
While no single email security technology can prevent every type of phishing or impersonation attack, properly configured SPF, DKIM and DMARC provide an important layer of protection against direct domain spoofing.
If your domain is hosted with Rhino Hosting, we can implement the initial DMARC record for you at no additional charge.
If you would like us to take the protection further, our managed DMARC service provides the monitoring, reporting and gradual policy hardening required to turn that record into a properly managed email authentication strategy.
Speak to Rhino Hosting about Managed DMARC Protection for your domain.
*All pricing quoted excludes VAT and is valid for 2026