This structured DataType describes the required information in a LogRecord. An array of this record type is returned in the LogObject GetRecords Method call.

The structure is formally defined in Table 4.

Table 4 – LogRecord structure

Name

Type

Description

Optional

LogRecord

Structure

Subtype of Structure defined in OPC 10000-5

Time

0:DateTime

Time associated with this record.

False

Severity

0:UInt16

Is a number between 1 and 1000 inclusive and corresponds to the range provided in the OPC UA BaseEventType (see OPC 10000-3). Additional details for mapping of the severity defined for OPC BaseEvents to LogRecords is described in Table 5.

False

EventType

0:NodeId

Describes the specific type of Event. It corresponds to the EventType field defined in BaseEventType.

If AdditionalData is provided then an EventType should be provided.

True

SourceNode

0:NodeId

Identifies the Node this record originated from. If the LogRecord is not related to a specific Node then this shall be set to a null NodeId.. Additional rules may be defined by other specifications that utilize the LogObject.

True

SourceName

0:String

Provides a description of the source of the LogRecord, this could be the string-part of the BrowseName of the SourceNode.

True

Message

0:LocalizedText

Shall describe the issue that is being represented in the LogRecord.

False

TraceContext

0:TraceContextDataType

This structure is used to correlate records inside of a Server along with corelating records between other Servers and Clients. The TraceContextDataType is described in 5.5.3.

True

AdditionalData

0:NameValuePair[]

Additional data for the log entry. This field contains the additional event fields of an LogEvent.

True

Severity ranges for Alarms and alerts are discussed further in OPC 10000-9. Diagnostic information typically has a Severity below the Alarm threshold of 400. Table 5 provides the Severity ranges that shall be used for LogRecords.

Table 5 – LogRecord Severity Mapping

Range Name

Severity Range

Diagnostics classification

Emergency

401 – 1000

Critical errors - errors that are fatal. This range can also be associated with Alarms.

Alert

300 – 400

Alerts are errors that are not raised to the Alarm level, but require some actions, typically by maintenance staff and could be recorded as part of an Alarm system.

Critical

251 – 300

Errors that can affect the overall process and need to be addressed.

Error

201 – 250

Errors related to important actions that were taken on the Server. They typically do not affect the overall process.

Warning

151 – 200

Warnings are issues that should be noted, but are not failures.

Notice

101-150

This level is typically used for significant or unusual successful actions that are taken on a Server.

Information

51-100

General Information related to an application.

Debug

1-50

Low level tracing information that can be used to debug the flow of an application.

The LogRecord representation in the AddressSpace is formally defined in Table 6

Table 6 – LogRecord definition

Attribute

Value

BrowseName

LogRecord

IsAbstract

False

References

NodeClass

BrowseName

DataType

TypeDefinition

Other

Subtype of the 0:Structure defined in OPC 10000-5

ConformanceUnits

LogObject Base