Switching Kepware servers in PCO

[darshansheth]

Hi Experts,

We have Kepware on a different machine and PCO on another machine. To connect the Kepware server we installed 'OPCCoreComponentsRedistributable(x86)' on the machine where PCO is installed. we were able to create a source system using the details of the kepware server. For some testing we are trying to re-point the PCO to another Kepware server. For configuring the other Kepware server, we made the changes to the 'opc_remote' file to specify the details of the other kepware server. After making the changes to the file, we re-started the server on which PCO is installed. After re-starting when i am trying to create a source system using the details of the new kepware server, i get message 'No OPC servers found on the specified machine'.

If i specify the other Kepware server that was provided earlier, i am still able to create the source system.

I know that we can connect to only one Kepware server from PCO, but is it that we cannot switch from one Kepware server to another.

We are on PCO 2.3 SP04 P7 and Kepware server is V4.190.341 - U.

Regards,

Darshan Sheth

[former_member196557 · Accepted solution]

Darshan,

What 'opc_remote' file are you referring to? PCo does not maintain any file like that, and neither does Kepware to my knowledge.

In order to connect to a remote Kepware instance using OPC DA Agent you have to peform DCOM configuration on PCo and Kepware servers to enable connectivity. Please refere to the Kewpare DCOM configuration document for guidance.

You can configure multiple PCo OPC Source Agents and each can connect to the same or different OPC Server, but on only One Agent can be referenced in an Agent Instance.

Also, recommend you upgrade Kepware to V5; your version is very old and may no longer be supported by Kepware.

Regards, Steve

[darshansheth · Accepted solution]

Steve,

Thanks for the response. In the Kepware support document, there is a section about 'opc_remote', which we have followed. Now after reading your feedback when we read it minutely, it says that the opc_remote file is required if the Kepware is not registered version. attached is the document for your reference.

we followed the same document and made the DCOM changes. Now we are able to create the source system in PCO. When we go to create an agent and try to browse the tags we get an error saying 'Browsing failed; check the connections and try again [Access is denied]'.

Any further help would be appreciated.

Thanks,

Darshan Sheth

[darshansheth · Accepted solution]

Kepware document is located at :

http://www.kepware.com/Support_Center/SupportDocuments/KTSM00010_Dcom_Configuration.pdf

[former_member196557 · Accepted solution]

Darshan,

'Access Denied' most likely means that you still do not have DCOM permissions correctly configured.  If you have Kepware also installed on the PCo server you should have the Kepware OPCQuickClient installed as well. Can you browse the remote server tags with that client?

Regards, Steve

[darshansheth · Accepted solution]

Hi Steve,

We do not have the kepware installed on the PCo server.

Are there some specific DCOM settings that would allow source system to be created but prevent the tags being retrieved from the source system. Having said that i am in the process of validating the DCOM permissions.

Regards,

Darshan

[former_member196557 · Accepted solution]

Your original message indicated that you could connect to one Kepware server and not another Kepware server. Are both Kepware servers remote from PCo? If so, you have to configure DCOM in order for PCo to have connected to any remote OPC Server.

We try to avoid DCOM where possible as it is always an effort to configure and maintain,

Are all PCo servers and Kepware Servers in the same domain? Are any Kepware servers located on other networks behind routers?

Regards, Steve

[darshansheth · Accepted solution]

Hi Steve,

All kepware servers are remote from PCo but all are within the same domain.

[former_member196557 · Accepted solution]

Darshan,

For DCOM to work with PCo and Kepware, you have 2 options to configure the user access:

1. Allow full DCOM access for domain users that are members of the server Administrators group, EVERYONE, SYSTEM and NETWORK, and allow PCo and Kepware services to run under LocalSystem account (some network admins will not allow this as it opens potential network security holes)

2. Define named users or named Domain Group permissions for DCOM.

2.1. Use the named user or users that are  members of the named Domain Group for the following:

    -  named user for Kepware server_runtime service

    -  named user for PCo Agent Instances

    -  administrative user to log into to PCo remote Desktop

Avoid hosting PCo and remote OPC Servers on different Domains or on Workgroups -- should always be in the same Domain.

I strongly recommend that you migrate to Kepware V5 and investigate using the Kepware OPC UA interface along with PCo OPC UA Agent where you are going to have remote OPC Server requirements, and avoid the DCOM issues altogether.

Installing Kepware on PCo server, or PCo on the Kepware server will remove any DCOM configuration requirements.

Regards, Steve

[darshansheth · Accepted solution]

Steve,

We have provided Local/Remote DCOM access to Group/user name 'Everyone' and 'ANONYMOUS_LOGON'. Launch permission has been given to Group/user name 'Everyone'.  Checked the DCOM settings on 'KEPware Enhanced OPC/DDE Server Properties' in the Component services, 'Everyone' has the Remote Launch and Access permission too.PCo and Kepware services are running under LocalSystem account.

Still getting the same error.

Do we need to make the changes on Kepware server as well as the PCO server or only on the Kepware server. After making the changes, do we need to reboot the server.

We had evaluated using Kepware OPC UA interface along with PCo OPC UA Agent, but because of the additional cost and the project timelines, client did not go ahead with it.

Regards,

Darshan

[former_member196557 · Accepted solution]

on the PCo server, please install the Kepware OPC Quick Client from the Kepware installer. You can just select this and not install any other kepware software. Then see if if you can connect to and browse tags on the remote Kepware server.

Regards, Steve

[darshansheth · Accepted solution]

Steve,

We are now able to connect to Kepware's at the different locations from PCo. Following were the steps we followed:

On PCo server, Navigate to Component services => My Computer =>Properties => Default Properties set the default authentication level to 'None'.

On Kepware server,

1) Navigate to Component services => My Computer => Properties => Default Properties set the default authentication level to 'None'.

2)  Navigate to Component services => My Computer => DCOM Config => KEPware Enhanced OPC/DDE Server => General => set the authentication level to 'None'.

Thanks.

Regards,

Darshan Sheth