Recommended Scenario

Linux DNS redundancy

Test your Linux-hosted service's availability when its primary DNS server is unreachable. Verify that DNS failover routes traffic correctly through secondary providers.

Experiment types

DNS

Targets

Linux

Length

5 minutes

How it works

How this Scenario works

This Scenario blocks DNS traffic on your Linux hosts, simulating a primary DNS provider failure. This tests whether your Linux systems' DNS resolver configuration (such as /etc/resolv.conf) correctly falls back to secondary DNS providers.

Use cases

Why run this Scenario?

DNS can fail in many ways, including:

  • Failures in nameservers and/or recursive resolvers, causing DNS queries to time out or return errors.
  • Network saturation (or a DDoS attack) slowing down DNS queries or causing them to drop.
  • Misconfigured Quality of Service (QoS) rules, causing the network to de-prioritize DNS traffic.

Running this Scenario can help:

  • Verify that Linux DNS resolver configuration supports failover to secondary DNS providers.
  • Validate DNS caching behavior and TTL settings on your Linux infrastructure.
  • Identify services that hard-code DNS server addresses instead of using system-level resolution.
  • Ensure that DNS failures on Linux hosts don't cascade into application-level outages.
Result

What to expect when you run it

If the primary DNS provider fails, services running on Linux hosts continue resolving DNS queries through secondary providers with no interruption.

Run this Scenario
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