How to Set Up DNS Uptime Monitoring

What is a DNS Check?

A DNS check queries a domain from Xitoring's global probing nodes and validates that the response matches what you expect. DNS issues are easy to overlook — a domain can resolve correctly from your office but fail from another continent, or a stale record can break email delivery while the website looks fine.

Use DNS checks for:

Authoritative domains you own
Critical subdomains that point to load balancers or CDNs
MX records that drive email delivery
TXT records used for SPF, DKIM, DMARC, and domain verification

What Gets Monitored

Resolution success — domain returns a valid response
Record value — answer matches the expected IP, hostname, or text
Record type — A, AAAA, CNAME, MX, TXT, NS, SOA, etc.
Response time — query latency from each probing node
Resolver consistency — propagation across regions and recursive resolvers

Prerequisites

The domain or subdomain you want to monitor (e.g., example.com, mail.example.com)
Knowledge of the expected record value so the check can assert correctness
Optionally, a specific DNS server to query (e.g., 8.8.8.8)

How to Set Up a DNS Check

Step 1: Create the Check

Log in to your Xitoring Dashboard
Go to Uptime → Add Check
Select DNS as the check type

Step 2: Configure the Query

Enter the domain name (e.g., example.com)
Select the record type (A, AAAA, CNAME, MX, TXT, NS, SOA)
Enter the expected value (e.g., 192.0.2.10 for an A record)
Optionally specify a DNS server to query — leave blank to use Xitoring's default resolvers
Set the check interval (30 seconds to 15 minutes)
Set the timeout (default: 30 seconds)

Step 3: Choose Probing Nodes

Pick at least 3 nodes spread across regions. DNS propagation issues often only show up from specific geographies.

Step 4: Assign Notifications

Under Triggers, attach a notification role.

Step 5: Save and Verify

Save the check. Xitoring queries the record immediately and reports back.

Setting Up Triggers

Common alerting rules:

Resolution failure — domain returns NXDOMAIN or SERVFAIL
Value mismatch — record exists but the value differs from expected (e.g., wrong IP after a botched migration)
Slow resolution — query time exceeds your threshold
Inconsistent answers — different probing nodes return different values (split-brain DNS)

Tips

Monitor your MX, SPF, and DKIM TXT records — broken email DNS is silent until customers stop receiving messages
Pin specific record values rather than just checking that the record exists — a typo'd CNAME pointing nowhere will still "resolve"
Use multiple probing nodes to detect propagation issues — a record can update in one region and lag in another
Check NS records to confirm authority hasn't been hijacked or accidentally moved
For CDN-fronted domains, expect the answer to vary by region — match on the expected pool of values rather than a single IP