Installing multiple instances of openHistorian in separate drives

Is it possible to install multiple instances of openHistorian in separate drives of the same system?

Certainly possible to target multiple drives from a single openHistorian:

You can install and configure multiple instances of the openHistorian on the same machine, but this is very manual process - picking unique ports per service instance, etc.

If this multi-instance thing is something you would like to try, let us know, I think we have some notes we can share on this.


Hi Ritchie,
Thanks for your reply. It would be really great if you could share some documents pertaining to it as we are planning to have two openHistorian instances on our machine.
Thanks and regards,

OK, we were able to post some instructions for this thanks to our friends at EPRI:

Thanks a lot Ritchie. Will definitely go through it.

Hi Ritchie,

We have installed 2 instances as per instruction provided by you.
Each instance web interface is working fine using differnet port.
But OpenHistorian Manager (tool) is always expecting instance 1.
Is there any settings for openHistorian Manager tool for pointing second instance?


I am assuming you have two different database for each instance. If so, running the Configuration Setup Utility should have properly connected the manager to right database. However, can easily manually verify these settings, open the openHistorian.exe.config and the openHistorianManager.exe.config - these are both XML files. The following settings in the openHistorian.exe.config file:

<?xml version="1.0" encoding="utf-8"?>
      <add name="ConfigurationType" value="Database" description="Specifies type of configuration: Database, WebService or XmlFile"
        encrypted="false" />
      <add name="ConnectionString" value="Data Source=localhost\SQLEXPRESS; Initial Catalog=openHistorian-Instance2; Integrated Security=SSPI; Connect Timeout=5"
        description="Configuration connection string" encrypted="false" />
      <add name="DataProviderString" value="AssemblyName={System.Data, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089}; ConnectionType=System.Data.SqlClient.SqlConnection; AdapterType=System.Data.SqlClient.SqlDataAdapter"
        description="Configuration database ADO.NET data provider assembly type creation string used when ConfigurationType=Database"
        encrypted="false" />
      <add name="NodeID" value="fc430c57-029e-47dc-9362-5fbe425401ad"
        description="Unique Node ID" encrypted="false" />

Should match in the openHistorianManager.exe.config file.

Note that the setting values in your XML config file will not match what’s listed above, they will be unique to your system, however, these are the “keys” that matter when connecting to a configuration database, i.e., ConfigurationType, ConnectionString, DataProviderString and NodeID.


Also note the Settings field in the Node table. You can adjust various port numbers used by the openHistorian Manager to connect to the service by modifying that field. I notice that the data publisher ports are not included in the instructions, probably because they were written specifically for setting up instances that will be used by openXDA.

One other thing that occurred to me… You will need to run “two” instances of the openHistorian Manager. One out of the first installation folder, and the second out of the second installation folder - that may not have been obvious from the instructions.

Oh and Stephen is right, this step may be missing from the instructions - see his note above…

You can change these values from within the openHistorian Manager, just go to System > Manage Nodes in the manager and make needed adjustments to ports.

Its mainly the RemoteStatusServerConnectionString={server=localhost:8510 (Remote Host Port) and dataPublisherPort=6175 (GEP) ports that need to be changed.

Looking back at the notes, I am not sure we added instructions to change ports for GEP and STTP, and I think we should have…

OK, the extra steps have been added to the instructions which should help you out:

Note that you should stop service instance before making changes to its config file.

Steps were updated to create unique ports for the hosted Grafana instance as well.

Thanks a lot Ritchie and Stephen for getting back. Will be implementing these changes and update you regarding the same.
Thanks and regards,