Just like the human body, your digital infrastructure needs checkups to perform at its best. Domain health checks are essential for ensuring that all systems are online and performing optimally. They use DNS to monitor system availability, performance, and configuration, helping organizations detect and resolve issues before they impact users.

What is a Domain Health Check?

Domain errors can have serious consequences for businesses. After all, your domain is a critical part of your brand and your digital infrastructure. However, despite the criticality of domains in modern business operations, many domains have errors that can leave them vulnerable. Data shows that an estimated 90% of businesses experience DNS attacks annually, and each attack can incur significant financial costs. This is where a domain health check comes in—it helps businesses find gaps in the configuration, integrity, and security of their domain. It examines technical components, including DNS records, email authentication protocols, server settings, and security measures, to ensure the domain is configured correctly, reliable, and protected against misuse or attacks. Here’s what a domain health check involves:

• DNS Queries: Checks the hostnames of mail servers, web servers, and DNS servers.
• Email Deliverability: Reviews MX records against blacklists to see if emails get rejected.
• Email Authentication: Reviews at SPF, DKIM, and BIMI records to verify email security.
• Performance Tests: Runs hundreds of tests for system functionality and performance.

The process is typically fast, often completing in just a few minutes, which means it doesn't put undue burden on internal teams. The results highlight critical areas that need attention by analyzing DNS resolution, email deliverability, and configuration issues. The results may flag missing or misconfigured DNS records, insecure protocols, or authentication failures that could impact performance or security. With these insights, organizations can proactively fix issues before they lead to outages, misdeliveries, or exploitation.

What is a Domain Scanner?

Domain scanners are tools used as part of the domain health check process. They quickly identify potential issues in your domain’s infrastructure by checking DNS records such as SPF, DKIM, DMARC, and BIMI. These tools help evaluate how well your domain is configured for email authentication, deliverability, and overall security. The key features of a domain scanner include:

• Sender Policy Framework (SPF) Record Check: Ensures email servers can verify which IP addresses are allowed to send emails on behalf of your domain.
• DomainKeys Identified Mail (DKIM) Authentication: Confirms that emails come from your domain and aren't spoofed.
• Domain-based Message Authentication, Reporting & Conformance (DMARC) Policy: Prevents email spoofing and phishing attacks.
• BIMI Records: Adds a brand logo to authenticated emails to enhance brand trust.

Using a domain scanner as part of a DNS health check is highly effective, as it provides a quick assessment and detailed insights into your domain’s security posture. This enables organizations to take immediate, proactive steps to resolve misconfigurations and protect their domain from potential threats.

Key Components of a Domain Health Check

So what exactly goes into a domain health check? There are several key areas that scanners analyze to identify potential issues and opportunities for improvement. Here's a high-level overview of what's included:

• Email Authentication (SPF, DKIM, DMARC): Verifies email legitimacy, helps block spoofing and phishing, and boosts inbox placement.
• Blacklist Monitoring: Checks if your domain or IP is flagged on spam blocklists like Spamhaus or Barracuda, which can impact deliverability.
• SMTP Testing: Confirms mail servers are reachable and properly configured to prevent hard bounces and silent failures.
• DNS Record Evaluation: Ensures A, MX, CNAME, TXT, and PTR records are correctly set up to direct traffic and support security protocols.
• MX Record Validation: Verifies that emails are routed to the correct servers with the proper priority settings.
• Ongoing Authentication Checks: Regular testing of SPF, DKIM, and DMARC alignment keeps email delivery consistent and secure.

Benefits of Maintaining Domain Health

A healthy domain directly supports smooth business operations, helping to avoid disruptions and downtime caused by email delivery failures or poor domain security. Here are a few key benefits associated with maintaining a healthy domain:

Improved Email Deliverability

Your domain reputation is used by Internet Service Providers (ISPs) to determine whether or not your emails are trustworthy. It's estimated that 21% of legitimate emails never reach customer inboxes due to poor domain reputation. Often, the issue lies with misconfigured DNS settings or MX records, which regular checkups can help prevent. Additionally, properly setting up SPF records and other email authentication protocols like DKIM and DMARC can help avoid spam flags and maintain email reliability. Finally, regular checkups can identify blacklist entries, allowing for timely remediation.

Enhanced Security and Reliability

DNS security is critical. Cyberattacks targeting DNS infrastructure can lead to service disruptions, data breaches, and prolonged downtime, ultimately damaging a brand's reputation and eroding customer trust. Regular health checks help detect misconfigurations and vulnerabilities early, thereby protecting against threats such as phishing, DNS hijacking, and failover failures. These checks include verifying DNS records (A, MX, TXT, CNAME, and PTR), confirming IP address integrity, and ensuring that core services, such as domain controllers and Active Directory, remain available and properly configured.

Increased Trust and Reputation

A well-maintained domain boosts trust and reputation. When users experience consistent uptime and reliable email delivery, their confidence in a business grows. Regular domain health checks help prevent issues like DNS resolution failures, which can damage credibility and interrupt service. Data shows that network and connectivity-related issues accounted for 31% of IT service outages in 2024, underscoring the importance of DNS reliability. Being proactive in domain management demonstrates a commitment to quality, reliability, and security. This ongoing diligence enhances a company’s reputation and enhances the user experience.

Challenges in Domain Health Checks

As with any other facet of internet operations, there are hurdles to maintaining healthy DNS and email infrastructure. First and foremost is scale. As organizations expand their digital footprint, managing DNS records, DNS servers, domain controllers, and email servers becomes increasingly challenging, especially in hybrid environments. Without real-time insights into domain performance, organizations risk missing early warning signs of trouble in critical systems, such as Active Directory, Windows Server, or web servers. Misconfigured DNS records, email server issues, or outdated settings can lead to performance degradation, phishing exposure. Maintaining email deliverability is also a challenge. Poorly configured email protocols (SPF, DKIM, DMARC, and BIMI records) can reduce deliverability and increase the risk of spoofing. This is a good way to land on an email blacklist and damage your domain reputation. It’s worth noting that there are over 300 active email blacklists (DNSBLs) used by ISPs and email providers to block spam or unwanted email sources.

What Domain Records Should Organizations Configure to Improve Domain Health?

There are several key DNS records organizations must configure correctly to maintain domain health and avoid issues. These records directly impact email authentication, security posture, and domain reputation, and, by extension, the performance of critical systems, such as email servers, domain controllers, and Active Directory-integrated services. Implementing records such as SPF, DKIM, and DMARC enables organizations to control outbound email flows, verify sender authenticity, and detect email abuse. Here's a look at each record that helps improve domain health:

SPF

SPF records allow domain owners to specify which IP addresses or mail servers are authorized to send email on behalf of their domain. This DNS TXT record prevents unauthorized servers from forging messages, reducing the risk of email spoofing. When a recipient receives an email from your organization, their mail server checks to see if the sending server's IP is listed in the SPF record. Without a valid SPF record, legitimate emails may be rejected or flagged as spam, which can harm deliverability and increase the likelihood of being added to an email blacklist. SPF records are added to the domain's DNS zone file, typically via your DNS host or Windows Server DNS Manager.

DKIM

The key question in every phishing simulation exercise is: How can you verify that an email sender is who they claim to be? Building upon SPF records, DKIM adds a cryptographic signature to the email header, allowing receiving servers to verify that the message was authorized by the domain owner and hasn't been altered in transit. DKIM signs outgoing emails with a private key, which the recipient verifies using the public key published in the domain's DNS. This protects against message tampering and improves inbox placement, especially when combined with SPF and DMARC. DKIM keys are managed in your DNS records, often via your ESP or mail gateway (e.g., Microsoft 365, Google Workspace).

DMARC

DMARC ties SPF and DKIM together, allowing domain owners to specify how receiving servers should handle failed authentication attempts and to receive forensic and aggregate reports. DMARC policies (none, quarantine, or reject) instruct recipients on how to treat emails that fail SPF and/or DKIM. It provides visibility into misuse attempts and sends reports to administrators for analysis. This is key for detecting spoofing attempts and protecting domain integrity. Like SPF and DKIM, DMARC is added as a TXT record in DNS and should be tuned based on insight from email traffic patterns and threat reports.

Maintain a Healthy Domain with DNS Made Easy

Your domain is a critical part of your business infrastructure; keeping it healthy and performative is essential. Choosing a DNS provider with a strong global network ensures a resilient and reliable digital experience. DNS Made Easy helps reduce the risk of DNS-based disruptions through continuous monitoring and advanced analytics, giving internal teams the visibility they need to enhance reachability and availability. Don't settle for less when it comes to your critical infrastructure. Explore how DNS Made Easy can elevate your DNS performance.