---
title: DNS Lookup
description: Resolve a domain name over the cellular connection and measure resolution time.
lastUpdated: "2026-09-23"
---

> **For AI agents:** the complete documentation index is at [llms.txt](/llms.txt). Append `.md` to any page URL for its markdown version.

Resolve a domain over the SIM's data connection. Verify the carrier's DNS answers correctly and track resolution time, a frequent hidden culprit in slow mobile experiences.

## Parameters

| Parameter | Required | Description |
| ----------- | ---------- | ------------- |
| Host | Yes | Domain to resolve, for example `kapptivate.com`. |
| DNS override | No | Query specific DNS servers instead of the carrier's. |
| DNS Lookup should fail | No | Invert the verdict, for domains that must be blocked. |

Plus the shared [connection settings](/tests/actions/cellular/overview#connection-settings).

## Results and metrics

In the action report (`result`):

| Field | Description |
|-------|-------------|
| `ip_addresses` | The resolved IP addresses. |
| `dns_server` | The DNS servers that answered. |
| `duration` | Resolution time in seconds. |

In Analytics, each run feeds the DNS measurement with `duration_seconds`, tagged by status, host, DNS server, APN, antenna, and access technology.

## What's next?

<Columns cols={2}>
  <Card title="HTTP Ping" icon="globe" href="/tests/actions/cellular/http-ping">

    Measure the full request once the name resolves

</Card>
  <Card title="Check SSL/TLS Certificate" icon="id-card" href="/tests/actions/cellular/check-certificate">

    Verify the certificate served on that domain

</Card>
</Columns>