In SharePoint 2013, some service applications can be shared across server farms.
By publishing a service application, you can optimize resources, avoid redundancy, and provide enterprise-wide services without installing a dedicated enterprise services farm. You can publish the following service applications in a SharePoint 2013 farm:
Business Data Connectivity
Additionally, a SharePoint 2010 farm can consume services from a SharePoint 2013 Server farm. This allows for upgrade of multi-farm environments in which a farm hosting service applications is upgraded first. In this scenario, the service applications and features that the SharePoint 2010 farm experiences are limited to those that are available in SharePoint 2010. For example, a SharePoint 2010 farm cannot consume the Machine Translation service application from a SharePoint Server 2013 farm and does not benefit from the new features of the User Profile service application.
There are significant restrictions on when services and content can be shared between a SharePoint 2010 farm and a SharePoint 2013 farm. Content type syndication uses the backup and restore mechanism in SharePoint Server to publish the content types across site collections. And backup and restore does not work across versions in the following scenarios:
Between a SharePoint 2010 farm and a SharePoint 2013 farm
Between sites in 2010 mode on a 2013 farm and those in 2013 mode on a 2013 farm
If the server farms are located in different domains, the User Profile service application requires both domains to trust one another. For the Business Data Connectivity service and Secure Store service application administration features to work from the consuming farm, the domain of the publishing farm must trust the domain of the consuming farm. Other cross-farm service applications work without a trust requirement between domains.
The User Profile service must reside in the same datacenter as the content it supports — The performance of social features require the User Profile service application to be located in the same datacenter as My Sites, team sites, and community sites.
The farm that contains the service application and publishes the service application so that other farms can consume the service application is known as the publishing farm. The farm that connects to a remote location to use a service application that the remote location is hosting is known as the consuming farm.
If you are familiar with SharePoint 2010, you might find it useful to think of the publishing farm as the parent farm and the consuming farm as a child farm.
This article describes the steps that are required to publish and consume service applications across farms. These steps must be performed in the order listed.
Exchange trust certificates between the farms.To start, an administrator of the consuming farm must provide two trust certificates to the administrator of the publishing farm: a root certificate and a security token service (STS) certificate. Additionally, an administrator of the publishing farm must provide a root certificate to the administrator of the consuming farm. By exchanging certificates, each farm acknowledges that the other farm can be trusted.For more information, see Exchange trust certificates between farms in SharePoint 2013.
On the publishing farm, publish the service application.On the farm on which the service application is located, an administrator must explicitly publish the service application. Service applications that are not explicitly published are available to the local farm only.For more information, see Publish service applications in SharePoint 2013.
On the consuming farm, set the permission to the appropriate service applicationsYou must give the consuming farm permission to the Application Discovery and Load Balancing Service Application on the publishing farm. After doing this, give the consuming farm permission to the published service applications that it will be consuming.For more information, see Set permissions to published service applications in SharePoint 2013.
On the consuming farm, connect to the remote service application.After the publishing farm has published the service application, an administrator of the consuming farm can connect to that service application from the consuming farm if the address of the specific service application is known.For more information, see Connect to service applications on remote farms in SharePoint 2013.
You cannot share a User Profile service application across farms that reside in separate domains unless you first establish a domain-level trust between the two domains.
Add the shared service application to a Web application proxy group on the consuming farm.An administrator must associate the new service application connection with a local Web application on the consuming farm. Only Web applications that are configured to use this association can use the remote service application.For information about how to configure a Web application proxy group connection, see Add or remove service application connections from a web application in SharePoint 2013.
It is important that you plan the proxy group layout before you add service applications to proxy groups.
Configure server-to-server authentication between the publishing and consuming farms.To allow a web application or an application service to request a resource from a web application on another farm on behalf of a user, you have to configure server-to-server authentication between the farms. For more information, see Configure server-to-server authentication between publishing and consuming farms.
Web applications or application services that request resources from an application service on another farm do not require server-to-server authentication