DomainKeys Identified Mail (DKIM) is an important part of email authentication. It helps verify that your emails haven’t been altered during transit and that your message (in fact) is from your domain.
While that might sound simple enough, it’s something we can’t take for granted, especially with the rapid rise of cyberattacks (and their tendency to originate with email).
However, managing multiple DKIM records can be downright difficult. The process is filled with potential pitfalls, from complex configurations to coordinating across various teams and services. Misconfigurations can lead to authentication failures that result in email service providers marking legitimate emails as spam or rejecting them outright.
Fortunately, we can help.
Below, we’ll walk you through everything you need to know about managing multiple DKIM records. We’ll give you plenty of best practices and strategies to navigate the complexities of DKIM management and keep your emails on track.
DKIM and its role in email security
DomainKeys Identified Mail (often just shortened to DKIM) is an email authentication method that detects forged sender addresses in emails. It works by adding a unique digital signature to the header of each email sent from your domain.
This signature is created using a private key that only your mail server can access. When the email is received, the recipient’s mail server uses the corresponding public key (published in your domain’s DNS records) to verify the signature. If the signature matches, it confirms that the email hasn’t been altered and is genuinely from the sender.
And that’s that.
This mark of authenticity prevents malicious actors from impersonating your domain to deceive recipients. It maintains the trust and security of your communications, which is especially important in an age where phishing attacks are becoming more prevalent (and more sophisticated).
Plus, it can improve your email deliverability. Email providers are more likely to trust emails properly authenticated with DKIM, which means your emails are more likely to land in recipients’ inboxes rather than being flagged as spam.
Challenges of managing multiple DKIM records
Managing one DKIM record is relatively simple, but things can get a bit more complicated when you introduce multiple DKIM records. However, it’s an essential practice if you use a variety of email services with multiple subdomains.
Here are some of the challenges you’ll face:
Complexity of configuration
Setting up and maintaining multiple DKIM records isn’t a straightforward process. Each email service and subdomain requires its own DKIM key, which must be correctly configured in the DNS records. This involves:
- Generating unique private-public key pairs
- Publishing the public keys in the DNS
- Correctly implementing the corresponding private keys on mail servers
The more services and subdomains you manage, the more complex this configuration becomes. Any mistake in the setup can lead to DKIM failures, and that means your emails could be marked as spam or not delivered at all.
Coordination across teams
DKIM management requires close collaboration between various teams within an organization, including IT, security, and marketing. Each team has a role to play:
- IT manages the technical setup
- Security double-checks that the keys are handled safely
- Marketing relies on email deliverability to reach customers
Without proper coordination, miscommunications and delays can occur, leading to misconfigurations or lapses in DKIM management. To keep everyone on the same page, you’ll need to establish clear lines of communication and define responsibilities.
Risk of misconfiguration
Incorrect DKIM configurations are a common issue that can have serious repercussions. Misconfigurations can occur in various ways:
- Using the wrong selector
- Publishing incorrect key lengths
- Failing to update expired keys
These errors can cause DKIM failures, undermining the authenticity of your emails and harming your domain’s reputation. Regular audits and automated tools help mitigate these risks, but the potential for human error is always there.

Best practices for managing multiple DKIM records
Managing multiple DKIM records can be daunting, but with the right strategies, you can streamline the process and improve your email security. Here are some best practices to help you better manage DKIM records across your domain.
1. Centralize DKIM management
Centralized tools or DKIM management platforms transform how you organize complex email ecosystems. A centralized management system allows you to generate, publish, and update DKIM keys from a single interface—this helps maintain consistency and reduce the likelihood of errors.
It also streamlines the entire DKIM process, making it easier to maintain and monitor your DKIM configuration across all email sources.
And we can help.
Valimail provides a robust solution for centralized DKIM management. Our platform automates the generation, publication, and rotation of DKIM keys to keep your email authentication up-to-date and correctly configured. Here’s how:
- Automated DKIM Configuration: Valimail’s platform automates the setup and maintenance of DKIM records, reducing the workload on your IT team and minimizing the risk of errors.
- Real-Time Monitoring: Our real-time monitoring tools alert you to any issues with your DKIM configurations, allowing you to address problems before they impact email deliverability.
- Comprehensive Management: Valimail centralizes the management of all your email authentication protocols, including DKIM, SPF, and DMARC.
2. Regularly audit DKIM records
Perform periodic audits of your DKIM records to double-check that they are correctly configured and up-to-date. Proactive audits help you catch any discrepancies, expired keys, or misconfigurations that could lead to DKIM failures.
3. Implement key rotation policies
Key rotation involves regularly updating your DKIM keys to minimize the risk of compromise and guarantee your email authentication is working properly. Rotating your keys on a set schedule reduces the chance of attackers exploiting old or exposed keys.
Sometimes, DKIM keys become compromised, but this doesn’t mean it’s the end of the world. If a DKIM key is accidentally exposed or compromised, a rotation policy guarantees it will be updated soon, minimizing potential damage.
4. Use unique selectors for different services
A selector is a string that helps identify the DKIM key used to sign an email. Using unique selectors for different services helps you easily pinpoint and address issues specific to each service (making troubleshooting more straightforward).
It also helps isolate potential security issues and reduce the risk of widespread compromise if one key is exposed. With unique selectors, you can manage and rotate DKIM keys for each service independently—this helps you update keys regularly without affecting other services.
5. Automate DKIM configuration and monitoring
Automating the configuration and monitoring of DKIM records reduces manual effort. Automation tools can handle the repetitive tasks of generating, publishing, and updating DKIM keys, and they can also monitor their performance. This provides up-to-date DKIM configuration, real-time alerts, and non-stop peace of mind.
6. Coordinate with third-party providers
Work closely with third-party email service providers to maintain a secure and reliable DKIM setup. You likely use plenty of different tools for everything from marketing campaigns and customer support to invoicing and transactional emails—work with these providers to guarantee they’re aligned with your DKIM policies and configurations.
7. Maintain comprehensive documentation
Keep detailed records of your DKIM configurations, key rotation schedules, and any changes you make to your setup. This documentation trail provides a clear record of your email authentication practices, making it easier to troubleshoot issues, train new team members, and guarantee continuity during staff transitions.
Centralize and streamline DKIM management with Valimail
Managing multiple DKIM records can be complex and time-consuming, but it’s something you’ll need to do if you have a variety of sending services and subdomains. And, fortunately, you don’t have to do it alone.
Valimail can help.
Valimail centralizes and streamlines your DKIM management. Our automated solutions make it easy to set up, monitor, and maintain your DKIM records and keys to guarantee your emails are always authenticated correctly. With Valimail, you can enjoy peace of mind from knowing your email authentication is in expert hands.
Ready to take your DKIM management to the next level? Valimail Monitor gives you insight into your DKIM management for free.