Replace custom-device targets in network monitors

• Latest Dynatrace
• How-to guide
• 6-min read
• Updated on Oct 01, 2026

Upgrade network availability monitors

What changes

Network availability monitors that use a custom-device expression in targetFilter must be updated to use supported IP addresses or hostnames in targetList.

Replacing a dynamic custom-device filter with a static target list changes how the monitor is maintained: new or changed devices are not added automatically. Assign an owner to keep the target list current.

Identify affected monitors

timeseries count(dt.synthetic.multi_protocol.executions),
  by: {dt.synthetic.monitored_entity_ids, dt.entity.multiprotocol_monitor, dt.synthetic.monitor.name}
| expand dt.synthetic.monitored_entity_ids
| filter contains(dt.synthetic.monitored_entity_ids, "CUSTOM_DEVICE")
| fields dt.synthetic.monitor.name, dt.entity.multiprotocol_monitor

GET /api/v2/synthetic/monitors?type=MULTI_PROTOCOL

GET /api/v2/synthetic/monitors/{monitorId}

dtctl query 'timeseries count(dt.synthetic.multi_protocol.executions), by: {dt.synthetic.monitored_entity_ids, dt.entity.multiprotocol_monitor, dt.synthetic.monitor.name} | expand dt.synthetic.monitored_entity_ids | filter contains(dt.synthetic.monitored_entity_ids, "CUSTOM_DEVICE") | fields dt.synthetic.monitor.name, dt.entity.multiprotocol_monitor' -o json --plain

The current monitor definition, not the execution query, determines whether the monitor must be updated. Before making changes, export the complete monitor definition so you can refer to the original target configuration later.

Resolve IP addresses for each custom device

For each referenced custom-device entity ID, retrieve its IP address through the Environment API:

GET /api/v2/entities/{customDeviceEntityId}?fields=properties.ipAddress

Record the required IP addresses before modifying the monitor. If the custom device has multiple addresses, confirm which addresses the monitor is expected to test. If the intended target can't be determined unambiguously, ask the monitor owner to confirm it before continuing.

Update monitor targets

Replace the unsupported custom-device expression in targetFilter with explicit IP addresses or hostnames in targetList. Change only the affected target definition and preserve the monitor's locations, frequency, request settings, constraints, tags, and outage handling.

Before (targets defined by a custom-device filter).

{
  "steps": [
    {
      "name": "ICMP check",
      "requestType": "ICMP",
      "targetFilter": "entityId == CUSTOM_DEVICE-XXXXXXXXXXXXXXXX",
      "targetList": [],
      "requestConfigurations": [...]
    }
  ]
}

After (targets defined by an explicit IP address).

{
  "steps": [
    {
      "name": "ICMP check",
      "requestType": "ICMP",
      "targetFilter": "",
      "targetList": ["192.0.2.1"],
      "requestConfigurations": [...]
    }
  ]
}

Send the complete updated monitor definition to:

PUT /api/v2/synthetic/monitors/{monitorId}

After the update, retrieve the monitor definition again and confirm that the intended configuration was stored.

For API details, see Update a network availability monitor.

Verify the upgrade

For every updated monitor, confirm that: