DNS Monitoring

DNS failures are uniquely disruptive because they affect every service at once. When an A record stops resolving, your website is unreachable. When an MX record is wrong, email stops delivering. When a CNAME is removed, every subdomain that depends on it breaks. Unlike application failures that might affect individual features, DNS problems cascade instantly across your entire Internet presence.

DNS changes are also frequently made without proper coordination. A developer updating infrastructure, a hosting migration, a registrar transfer — any of these can introduce an unintended DNS change. Without monitoring, that change may not be discovered until customers report problems, by which point the damage is done.

DNS propagation adds another layer of risk. Even a correct DNS change takes time to propagate across the global resolver network. During that window, some users may see the old record and others the new one — leading to inconsistent behavior that is difficult to diagnose without visibility into what different resolvers are returning.

The business impact rarely stays contained to one system. An email outage caused by a broken MX record affects sales, support, and billing simultaneously, and a domain hijack discovered late can mean reputational damage that outlasts the technical fix by months.

NetTests queries your configured DNS records — A, AAAA, MX, TXT, CNAME, NS, SOA, and more — on a schedule you define. Each query is issued against multiple independent resolvers so you can detect propagation inconsistencies as well as authoritative server failures. The responses are compared against the previously recorded baseline, and any change — in record value, TTL, or resolver behavior — triggers an alert.

You can monitor for the presence or absence of specific values, verify that DNSSEC validation passes correctly, and track TTL values over time. NetTests stores the full response for every check, giving you a complete history of how your DNS has changed over time — invaluable during incident investigations and post-mortems.

For critical records like MX and SPF, DNS monitoring integrates with email health checks so that a change to your email authentication records surfaces in the same dashboard as your DNS record history.

Alerts reach your team through email, Slack, Microsoft Teams, or SMS — choose any combination per monitor. The dashboard shows every record you track, the resolvers it was checked against, and a timeline of every value it has ever held, so a propagation issue or an unauthorized change is easy to trace back to the exact moment it happened. Time to first alert is typically under a minute from the moment a change is confirmed across resolvers.