SharePoint [architecture series]-Server Object Model of SharePoint 01. physical object hierarchy

The content of the server-side object model of Sharepoint is very huge and complicated. In fact, we only sort out the most critical objects here. We will roughly describe them from three systems.

These three systems are:

1. physical objects hierarchy)

2. content hierarchy)

3. Services hierarchy ).

We hope that our general description will give you a general understanding of the Sharepoint Server-side object model. Enter the topic.

Here we will first look at the physical object hierarchy (physical objects hierarchy)

The objects represented by classes in the physical object hierarchy can be actual physical objects (spfarm, spserver) or) objects that are considered physical objects or non-physical objects (spfolder, spfile ).

ShownFour main classes in the hierarchy.

 

The two most important classes are servers and farms.

SharePoint fundation farm and Its configuration database are represented by the sfarm class.

Sharepoint Server Farm (farm) is a physical server cluster, which includes one or more front-end servers, zero or more application servers) as well as the SQL Server, the SQL server may be stored on a dedicated database server (dedicated database server). Although Sharepoint is not installed on this dedicated database server, it is still a member of the SharePoint field, we can see them on the Management Center interface of the SharePoint farm) or on one of the application servers (for example, on a front-end server ). (Strictly speaking, Windows SharePoint Services 3.0 is always deployed on site, although it may be the only computer in the entire deployment environment.

Physical servers in the SharePoint Foundation farm have IP addresses and roles. Below isThree (or four) roles that a server in SharePoint foundation may have:

1. Single Server ):The name indicates that the server has this role only when the server is the only server in the field.

2. Front-end web server ):Multiple servers can have this role. The Front-End Server accepts HTTP requests from client computers. Because the front-end server provides content to respond to these requests, the front-end server must run content publishing Web applications.

3. Application Server ):Any SharePoint Foundation server that is not used as a front-end server or a single server has an application server role (for an exception, see Figure 4 ). These servers run dedicated SharePoint Foundation Web services or Windows Services that must be detached from the front-end server because they require a large amount of server processor, hard disk, or other hardware resources. SharePoint foundation comes with services that are often uninstalled to the application server. developers can use the SharePoint Foundation object model to develop other services and run these services as part of the SharePoint Foundation deployment. A given web service or Windows service can run on multiple application servers. For example, the search service can run on multiple servers. Each server has a separate instance of the service.

4. Dedicated Database Server ):The exception mentioned above refers to the server that carries the SQL Server database. This database can be deployed on any application server, but if the scale of SharePoint Foundation deployment is large enough to require multiple server farms, the database will need its own server (which may be a server Image Cluster ). When the database is located on its own dedicated server (or cluster), it does not even install SharePoint Foundation on this server. The configuration database of the farm will identify this server, and this server will make the farm think it is running a service called "Windows SharePoint Services Database Service". In fact, this service is only the alias of the SQL Server service running on the database server. SharePoint foundation is usually not installed on this private server, and this private server actually does not have a role in the farm.

 

Load Balancing:

If the SharePoint farm has multiple front-end web servers, they usually require load-balance support. You can use hardware or software-supported Load Balancing solutions (including windows server2008 built-in network load balancing (NLB: network load balancing) solutions ). What you need to know is:SharePoint itself does not support Load Balancing solutions!

After the Server Load balancer solution is used, the system will direct the incoming network connection of the client computer to the end computer that was not busy at the time. In this way, the workload of the client that executes the service will be distributed to multiple servers, and then distributed to multiple processors, hard drive and other peripheral devices, so that the client can achieve better performance. In addition, if a server crashes, other servers can continue to process all incoming connections. At this point, the service speed may slow down, but the service will not be completely stopped.

Because the field appears as a single server in an external network, if a client computer wants to access a resource (such as a specific application, file, database, or webpage) in the field ), this client computer does not care (usually unknown) which physical server they will connect to in the field, so it must perform the same configuration for all the computers that the client may connect.

The simplest way to complete the same configuration is, install the same application on all computers and place copies of any required files, databases, and web pages on all computers (using the same directory path ). However, since this method requires that each change made by the client to any other item retained on the file, database, or server be propagated to all other servers, it is almost impossible. To ensure that the server is synchronized, the field must prevent incoming connections during transmission. The performance reduction caused by all propagation will make the advantages that the field should provide no longer exist. In fact, even a moderately used SharePoint Foundation deployment will be stuck in the state of almost continuously spreading changes. To avoid these problems, you can assign special tasks to some servers in the field, such as carrying databases. Although the front-end servers connected to the client do not copy the databases to them, they still need to perform the same configuration, because these servers will use the same connection string and network address to access the database.

 

About the spfarm class

The spfarm class inherits from sppersistedobject, which represents a field composed of one or more physical servers. Therefore, it is included in the physical layer.

However, it can also be considered as the top level of content hierarchy. For example, all Windows SharePoint Services (non-configuration) content can be backed up and restored.

In Windows SharePoint Services 3.0, the spfarm class can also be considered as a representative of the configuration database related to the server farm, because Windows SharePoint Services 3.0 does not represent the class for configuring the database. For example, the displayname attribute of the spfarm object is also the name of the configuration database.
Spfarm objects have three major child types: spserver, spservice, and spsolution.
Spfarm inherits from sppersistedobject, meaning that its object (only one) is saved in the configuration database.
Static members of spfarm can create server farms and return local or remote server farms.
Many members of the spfarm class can be used to develop management functions. More important members can be used to help management, as shown below:

• Backup and restoration of the farm (Backup and Restore server farm)
• Upgrades of the farm (upgrade server farm)
• Migration of (moving) the farm (upgrade server farm)
• Error Reporting)
• Caching)

The following are some features of the SharePoint Foundation farm (farm:

• Each SharePoint Foundation farm has a configuration database that contains information about the farm, the server of the farm, and other important sub-classes of the farm.
• The field is a level of the object model. You can install the SharePoint Foundation solution at this level, or deploy the solution to the server and SharePoint Foundation web application (Web Application) at this level ).
• A field is one of the four levels from which the SharePoint Foundation feature (feature) can be activated. The other three levels are websites, website sets, and Web applications.

About the spserver class

The spserver class represents a physical server in the Windows SharePoint services field.

In addition to many inherited members, the spserver class has an address attribute that stores the IP address of the server. The role attribute of the spserver class is used to distinguish server roles. If there is only one server, its role is singleserver.

If more than one server exists, the role of the front-end server is webfrontend, and the role of almost all other servers is application.

However, the attribute value of the server role hosting the Windows SharePoint Services content server is invalid. Because this server only runs one Windows SharePoint service-Database Service (One Windows Service)-This database service is actually the alias of SQL Server Windows service, this SQL Server Windows service is not part of Windows SharePoint service. Therefore, it does not actually run any Windows SharePoint service code and does not apply to application roles.
The spserver class also has a serverinstances attribute that returns all Windows Services and Web Services instances on the current server.
Spserver inherits from sppersistedobject, and all sppersistedobject instances are saved in the configuration database.

Reprinted: http://www.cnblogs.com/wsdj-ITtech/archive/2013/01/02/2559254.html