Create new service application from existing sharepoint install

To create a new service application from an existing SharePoint install, you can follow these steps:

Prerequisites:

Step 1: Open the SharePoint Management Shell

Open the SharePoint Management Shell by searching for "SharePoint Management Shell" in the Start menu (Windows) or Spotlight (Mac).
Alternatively, you can open the SharePoint Management Shell by navigating to the SharePoint installation directory, then running the "SharePoint Management Shell" executable.

Step 2: Connect to the SharePoint farm

In the SharePoint Management Shell, type the following command to connect to the SharePoint farm:
```
Add-PSSnapin Microsoft.SharePoint.PowerShell
```
This command loads the SharePoint PowerShell snap-in, which allows you to interact with the SharePoint farm.

Step 3: Create a new service application

To create a new service application, type the following command:

New-SPServiceApplication -Name <ServiceApplicationName> -ApplicationPool <ApplicationPoolName> -DatabaseName <DatabaseName>

Replace <ServiceApplicationName> with the name you want to give your new service application.
Replace <ApplicationPoolName> with the name of the application pool that will host the service application.
Replace <DatabaseName> with the name of the database that will store the service application's configuration and data.

For example:

New-SPServiceApplication -Name "My New Service App" -ApplicationPool "My App Pool" -DatabaseName "My Service App DB"

Step 4: Configure the service application

After creating the service application, you'll need to configure it. You can do this by running the following command:
```
Get-SPServiceApplication -Name <ServiceApplicationName> | Set-SPServiceApplication -DatabaseName <DatabaseName>
```
Replace <ServiceApplicationName> with the name of the service application you created in Step 3.
Replace <DatabaseName> with the name of the database that you specified in Step 3.

For example:

Get-SPServiceApplication -Name "My New Service App" | Set-SPServiceApplication -DatabaseName "My Service App DB"

Step 5: Start the service application

To start the service application, type the following command:
```
Start-SPServiceApplication -Name <ServiceApplicationName>
```
Replace <ServiceApplicationName> with the name of the service application you created in Step 3.

For example:

Start-SPServiceApplication -Name "My New Service App"

That's it! You've created a new service application from an existing SharePoint install.