Advanced DNS Synthetic Monitor


This guide provides instructions on how to create a DNS Synthetic Monitor leveraging many of the more advanced features. These parameters will help you to fine tune your monitors in order to get the most out of them.

Using the instructions provided in this document, you can create a DNS Synthetic Monitor to validate and alert on the health and performance of your DNS endpoints and records. This how-to will configure a CNAME monitor but you may select any record type for your needs.


Configure a DNS Monitor

Step 1: Create a new DNS Monitor.
  • Log into the F5® Distributed Cloud Console.

  • Navigate to either the Observability workspace tile or menu.

Note: The homepage is role based, and your homepage may look different due to your role customization. Select All Services drop-down menu to discover all options.

obs tile
Figure: Observability Tile
obs service list
Figure: Observability Menu
  • Select Manage > Synthetic Monitors > DNS Monitors.
manage menu
Figure: Manage Menu
  • Click Add DNS Monitor.
Step 2: Configure Metadata.
  • Enter Name, Labels, and Description as needed.
meta data
Figure: Metadata
Step 3: Configure the monitor Domain, type, interval, and protocol.
  • Enter the Domain that you would like to monitor.

  • Select the Record Type of the domain you would like to monitor.

  • Set the monitor frequency Interval for how often you would like the monitor to run from each source region configured later in the form.

  • Adjust the protocol if you are not using UDP.

what to monitor
Figure: What to Monitor
Step 4: Configure where to monitor from.

Note: Each source provider and region added will monitor the endpoint configured for the monitor. The combined health from all regions will generate the overall monitors global health.

  • In the Sources section, click Add Item to begin adding sources for the monitor.
empty sources
Figure: Empty Sources
  • Select the desired Provider for which you would like to source the monitor from.

  • With the Provider selected, click the Regions dropdown and select which Region you would like the monitor run from.

  • Select additional regions from the dropdown if you would like to add more Regions for the current Provider.

provider regions
Figure: Provider Regions
  • Click Apply to add the current Provider and Regions to the monitor.

  • Back in the primary Sources section, select Add Item and follow the steps above if you would like to add additional Providers and Regions.

sources complete
Figure: Sources
Step 5: Configure how to monitor.

Note: Custom nameservers are optional and the monitor will use its default nameservers for validation by default. Each configured Region will monitor each nameserver configured here.

  • Click Add Item on Custom Name Servers to add a specific nameserver you would like checked by the monitor.
add nameserver
Figure: Add Nameserver
  • Fill in the Name Server IP and Port to match your desired DNS infrastructure. You can click Add Item again if you require additional nameservers.
filled servers
Figure: Added Nameservers
  • Update the Query Timeout (ms) to control how long the monitor waits for a response before becoming critical.

  • Update the Number of consecutive test failures to control how many failed monitors must happen in a row before becoming Critical.

  • Update the Number of Nameservers to control if ANY or ALL nameservers tested must pass to be considered Healthy.

  • Update the Number of Failed Locations to control how many regions must fail before the global monitor becomes Critical.

  • Optionally enable Health Policy to set a dynamic and/or static threshold when determining the health.

filled how
Figure: Completed How to Monitor
  • Select Save and Exit to save the new DNS Synthetic Monitor.
Step 6: Setup Alerting.
  • Alerting for Synthetic Monitoring can be configured similar to other F5® Distributed Cloud services following the Alerting how-to guide.

  • Optionally filter your Alert Policy to only send notifications to the receiver based on alerts coming from Synthetic Monitoring by either matching the Group to Synthetic-Monitors or matching the Alert Name to SyntheticMonitorHealthCritical

Figure: Alerting

How To's


API References