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12.6 ServerState ToC Previous Next

This DataType is an enumeration that defines the execution state of the Server. Its values are defined in Table 212.

Table 212 – ServerState values

Name Value Description
RUNNING 0 The Server is running normally. This is the usual state for a Server.
FAILED 1 A vendor-specific fatal error has occurred within the Server. The Server is no longer functioning. The recovery procedure from this situation is vendor-specific. Most Service requests should be expected to fail.
NO_CONFIGURATION 2 The Server is running but has no configuration information loaded and therefore does not transfer data.
SUSPENDED 3 The Server has been temporarily suspended by some vendor-specific method and is not receiving or sending data.
SHUTDOWN 4 The Server initiated a shut down or is in the process of shutting down. This ServerState is intended as an indication to Clients connected to the Server to orderly disconnect from the Server before the Server completes the shut down.
TEST 5 The Server is in Test Mode. The outputs are disconnected from the real hardware, but the Server will otherwise behave normally. Inputs may be real or may be simulated depending on the vendor implementation. StatusCode will generally be returned normally.
COMMUNICATION_FAULT 6 The Server is running properly, but is having difficulty accessing data from its data sources. This may be due to communication problems or some other problem preventing the underlying device, control system, etc. from returning valid data. It may be a complete failure, meaning that no data is available, or a partial failure, meaning that some data is still available. It is expected that items affected by the fault will individually return with a BAD FAILURE status code indication for the items.
UNKNOWN 7 This state is used only to indicate that the OPC UA Server does not know the state of underlying system.

Its representation in the AddressSpace is defined in Table 213.

Table 213 – ServerState definition

Attributes Value        
BrowseName ServerState        
IsAbstract FALSE        
References NodeClass BrowseName DataType TypeDefinition ModellingRule
Subtype of the Enumeration DataType defined in Table 143.          
HasProperty Variable EnumStrings LocalizedText[] PropertyType  
Conformance Units          
Base Info ServerType          

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