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This section is regularly updated on the company web page, please the link: http://www.saeautom.sk/products/snmpopcserver/faq.htm

1.What SNMP protocols are implemented in SAEAUT SNMP OPC Server?  
·SNMPv2c.  
·SNMPv1.  

2.What OPC interfaces are implemented in SAEAUT SNMP OPC Server?  
·OPC Data Access 3.0, 2.05 and 1.0.  
·OPC Alarm and Events 1.0.  
·OPC XML Data Access 1.01 (Part of installation package is the OPC XML-DA Wrapper which provides an OPC XML-DA Web Service interface as a front-end to one or more OPC COM DA 2.x and 3.0 servers.)  

3.The first start of SAEAUT SNMP OPC Server.  
Recommendation: Please read more about this issue in User's Guide topic "The first start of SAEAUT SNMP OPC Server application".

4.The first start of SAEAUT SNMP OPC Server passed successfully, but Quality of items is "Bad" and the item Subquality is "Comm Failure".  
Recommendation: It is recommended to download the latest white paper which addresses this issue from link link http://www.saeautom.sk/download/install_snmp_service.pdf. The white paper is called Installation & Activation of the SNMP Service and SNMP Trap Service.

5.Writing the value on data item doesn't work. Why?  
·Data item is read only: Check the rights of data items you are using. Open SAEAUT SNMP Server Configurator and choose data item. Change the rights to Read/Write.  

·Community of the device is read only: Check the rights of the community you are using. When the device is PC, in administrative tools choose services and SNMP service. Open SNMP service Properties dialog and choose Security tab. Check Accepted community names and choose the community you are using. Change the rights to READ WRITE. You can add your own communities with desired rights and use them when configuring the device.  

6.Which communication ports does the SAEAUT SNMP OPC Server exploit?  
SNMP communication (between SNMP OPC Server and SNMP device):
·SNMP (UDP 161)  
·SNMP Trap (UDP 162)  

OPC communication (between SNMP OPC Server and OPC Client):
·OPC (TCP 135)  

XML-DA communication (between SNMP OPC Server and XML-DA Client):
·XML-DA (HTTP/SOAP 80)  

Heartbeat communication
(between SNMP OPC Server and SNMP device):
·Heartbeat (ICMP Echo (ping) request; ICMP Echo (ping) reply). ICMP is Internet Control Message Protocol.  

Be aware that according to required communication is necessary to permit a port in your firewalls. Settings of the standard operating system firewall are made automatic during installation.

7.Which ports are used in the SNMP communication?  
SNMP uses the default UDP port 161 for general SNMP messages and UDP port 162 for SNMP trap messages. If these ports are being used by another protocol or service, you can change the settings by modifying the local Services file on the agent. The Services file is located in \%SystemRoot %\System32\Drivers\Etc

8.The SAEAUT SNMP OPC Server doesn't receive any traps? Why?  
Please try to check the Windows Firewall whether the SNMP trap messages use allowed. The SNMP trap messages use default UDP port 162.

To enable SNMP trap messages in Windows Firewall, please do the following:

1.Click on the Windows Start ð Control Panel ð Windows Firewall.  
2.In the Exceptions tab click on Add Port and in the associated dialog fill out the fields as follows:  
·Name: SNMP Trap  
·Port number: 162  
·Select the UDP radio button.  

Note that: The SNMP trap messages may be received on another UDP port as well. Please see more in the next point: Which ports are used in the SNMP communication?

9.How to configure OPC and DCOM?  
Please refer to the document Configuring OPC and DCOM for OPC server and client applications from SAE – Automation, s.r.o. that describes OPC and DCOM settings in detail - available in Windows Start ð SAEAUT SNMP OPC Server ð Configuring OPC and DCOM.

10.How to make SAEAUT SNMP OPC Server data available via Internet/Intranet?  
Recommendation: Please read more about this issue in User's Guide topics "How to access SAEAUT SNMP OPC Server data through Internet." and associated sub-topics.

11.How is it possible to verify that XML-DA wrapper has been installed correctly?  
Recommendation: Please type the URL in the internet browser as follows: http://localhost/XmlDaSnmpOpcServerWrapper/Service.asmx. If the XML-DA wrapper is working correctly you will see a web service test page which will inform you about all operations which are supported (it is a standard test page for all ASP.NET web services).

12.If the XML-DA wrapper is installed successfully and working, how should we get the related web services' WSDL?  
Recommendation: If the web service test page is working, just click on "Service Description" link on the top of the screen to display web service's WSDL or visit the following link
http://localhost/XmlDaSnmpOpcServerWrapper/Service.asmx?WSDL
.

13.Why is it not possible to overwrite the data items browsed and added by MIB Browser?  
SNMP variables browsed from device do not contain information about access rights of variable and by default all the items added to configurator by browsing have access rights set to read only to avoid misusing. Such variables are not possible to overwrite from the client and it is user's task to change access rights and all desired properties of the data item. Properties of data items including access rights are possible to change from user interface of configurator. Please read more about this issue in User's Guide topic "Data Item".

14.In data item definition: Why does the data item validation fail?  
Validation of data item can fail in following cases: device supposed to have SNMP agent with desired SNMP variable is not connected or is incorrectly defined. Check IP address and community of device. Or: desired SNMP variable is not a leaf variable of a MIB Tree. Only leaf variables are readable from the device and valid able. Check the Object ID of the SNMP variable. To be sure about Object ID, you can browse all the SNMP variables of the device from a specified default Object ID. If you do not wish to browse all the SNMP variables of the device, specify different default Object ID that is closely to the desired you are looking for. For example, if you are not sure about OID: .1.3.6.1.2.1.25.3.2.1.3, if it is a leaf node, put it into Default OID and press Get button for SNMP request. If it is a branch node, all the nodes below will be browsed and you can access wished Object ID. See MIB Browse help.

15.Why OPC client cannot read Script items or Data items that use scripting?  
Reading of Script items or Data items that use scripting fails when any of the used scripts fails to be parsed. If any script fails to be parsed, no script is executed for any item. Check the scripts that you defined in the configurator, if there are no illegal characters or programming errors.

16.When does adding of MIB browser items into configurator throw an error?  
If adding of browse items into configurator fails and throws an error, it is usually because items supposed to be browsed would not be unique in a project file. It happens when attempting to write to the project file that is not active. Make sure that the project file is set to active and try browsing again. Please read more about this issue in User's Guide topic "Make Active".

17.How to activate product to full version?  
In order to activate your software product to full version you will need to enter a name and the license key. Please start the product you want to activate and click Enter key when asked about product registration. You will be presented with a dialog window that shows hardware fingerprint. Please e-mail us this fingerprint and tell us the Name under which you'd like to activate your product. Based on this information we will send you back the license key that can be used to activate your product.

 

 


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