DNS change detection

DNS monitoring catch changes instantly

Track DNS records across all your client sites and get alerted the moment something changes. Detect unauthorized modifications, failed migrations, and misconfigurations.

# dns records: clientsite.com

A (Address)

A104.21.55.12
TTL 5 minutes
A172.67.134.56
TTL 5 minutes

CNAME (Canonical Name)

CNAMEclientsite.com
TTL 1 hour

MX (Mail Exchange)

MX10 mail.google.com
TTL 1 hour
MX20 mail2.google.com
TTL 1 hour

TXT (Text)

TXTv=spf1 include:_spf.google.com ~all
TTL 1 hour

Why DNS monitoring

Protect against silent DNS failures

DNS changes can break email delivery, redirect traffic to the wrong server, or indicate domain hijacking. For agencies managing client domains, undetected DNS changes are a ticking time bomb. Sentinel watches every record and alerts you instantly.

  • Track A, AAAA, CNAME, MX, NS, TXT, and SOA records
  • Automatic baseline snapshots for change detection
  • Instant alerts when any record changes unexpectedly

7

Record types

24/7

Continuous scanning

<1m

Change detection

100%

Record coverage

Features

Complete DNS visibility

7 record types

Monitor A, AAAA, CNAME, MX, NS, TXT, and SOA records. Full coverage of your client's DNS configuration.

Baseline snapshots

We take a snapshot of your DNS records when monitoring starts. Every check is compared against this baseline.

Change detection

Instantly detect when a DNS record is added, removed, or modified. No change goes unnoticed.

Instant alerts

Get notified via email, SMS, Slack, or webhooks the moment a DNS change is detected.

Incident history

Every DNS change creates a detailed incident record showing exactly what changed, when, and the old vs new values.

Bundled with uptime

DNS monitoring runs alongside your uptime checks. Enable it when creating a monitor, with no extra configuration needed.

Change log

See exactly what changed

Every check is compared against the baseline snapshot we took when monitoring started. When a record is added, removed, or modified, we open an incident that records the old value, the new value, and the moment it flipped.

DNS changes detected

changed

MX (Mail Exchange)

10 smtp.oldhost.net10 mail.google.com

added

TXT (Text)

v=spf1 include:_spf.google.com ~all

FAQ

DNS monitoring questions.

Still have questions? Get in touch.

Which DNS records does Sentinel monitor?

DNS monitoring watches your A, AAAA, MX, and NS records for changes, so you can see when an address, mail, or nameserver record is modified.

How will I know when a DNS record changes?

Sentinel alerts you the moment a change is detected. Notifications can be sent via email, SMS, Slack, Discord, and webhooks.

Why does an unexpected DNS change matter?

Unexpected DNS changes can break email delivery, send traffic to the wrong server, or signal a domain hijack. Catching them quickly lets you respond before clients are affected.

Can I monitor DNS for all of my client domains?

Yes. Sentinel is built for agencies and freelancers, so you can monitor DNS records across every client domain from one account.

Does DNS monitoring work alongside other checks?

Yes. DNS pairs with the other monitor types Sentinel offers (HTTP/HTTPS uptime, SSL certificate, domain expiration, keyword, JSON/API response assertions, ICMP ping, TCP port and heartbeat/cron checks), so you can mix the right combination for each site.

Is there a free trial?

Yes. Paid plans include a 14-day free trial, there is also a free plan, and you can cancel anytime.

Never miss a DNS change again

Start monitoring DNS records across all your client sites.

No card for the free plan · 14-day trial on paid plans · Cancel anytime