Escalation Levels

The OPC Router detects when too much status data is being generated or when the database storage is nearly full. To prevent the hard drive and memory from becoming full, it automatically initiates increasingly stringent countermeasures and tracks them according to an escalation level ranging from 0 to 4.

These measures apply exclusively to status logging. The transfer of user data is not adjusted at any level—logging is throttled so that the transfer can continue.

You can set the limit on how full the status database is allowed to become under “Maximum Database Size” (default value: 8 GB), along with the “Ring Buffer Size” (default value: 2,000 entries). Both settings are located at Status Storage Options › Diagnostic Data Logging .

When a level is reached

Three metrics are monitored independently of one another. Each of them triggers a level on its own; the highest of the three levels applies (OR condition), not their sum.

Metric	Reference	Check Interval
Status database fill level	the set maximum database size	60 seconds
Ring buffer fill level	ten times the set size of the ring buffer	10 seconds
Free disk space	the free space on the storage device, only for local installation	cyclical

The Levels

Level	Trigger—any one of the three conditions suffices	Action
0	No threshold reached.	Normal operation; full logging is enabled.
1	Status database 60% full · Ring buffer at three times the set size	For flows that trigger particularly frequently, the detailed data for successful transfers is no longer recorded.
2	Status database 80% full · Ring buffer at four times the set size	The detailed data for all successful transfers is no longer recorded.
3	Status database 90% full · Ring buffer at seven times the set size · Less than 2000 MB of free disk space	Detailed data for all transfers is no longer recorded, including that of failed transfers; data already queued is discarded during writing.
4	Status database 100% full · Ring buffer at ten times the set size · Less than 500 MB of free disk space	The ring buffer no longer accepts status data. Even data that has already been buffered is discarded.

note

The fill level may be displayed as more than 100% because the limit refers to the user data in MongoDB and does not take into account the additional metadata generated. An explanation can be found at Status Storage Options.

Return to a lower level

The OPC Router automatically reverts to a lower level as soon as the measured values fall below the thresholds again. There is no hysteresis: The same thresholds apply to downgrading as to upgrading, and the level is redefined during the next check cycle—that is, after 10 seconds at the latest for the ring buffer and after 60 seconds for the status database. A restart or manual intervention is not required for this.

A level that remains active for an extended period is therefore an indication of a persistent mismatch between the recorded data volume and the set limits—not a one-time spike.

Where to Read the Level

• In the settings dialog: Status Storage Options › Diagnostic Data Logging displays the current level on a scale from 0 to 4, along with the conditions and actions for each level and the reasons for the current classification.
• In the “Event Logs” of the Service Status : Every change in level is logged and, as long as the level persists, repeated every five minutes.
• In a flow’s status chart: The time period during which recording was completely suspended at Level 4 appears shaded gray—see Flow status .

What You’ll Notice

At levels 1 through 3, the detailed values for individual transfers are missing from the status chart, even though the transfers themselves are running. At level 4, nothing is recorded at all.

As long as status logging is disabled, the OPC Router will also stop sending email notifications—see Notification Groups.

What You Can Do

• Increase Limits: Under Status Storage Options › Diagnostic Data Logging , increase the maximum database size (if there is space on the storage device) or the size of the ring buffer.
• Record Less: Assign a more economical diagnostic memory to flows that trigger frequently—Max10Entries retains only the last ten executions per flow, Discard saves nothing at all. The memory is selected per flow under Settings for Flows and Templates ; the memory is created under Status Storage Options .
• Freeing up disk space: Levels 3 and 4 may depend solely on available disk space. In this case, check the disk before adjusting the thresholds.

You can see whether the measure was effective in the same location: The level will drop in the next check cycle.