Friday, 14 August 2015

Tableau Server Architecture

Tableau has a highly scalable, n-tier client-server architecture that serves mobile clients, web clients and desktop-installed software.Tableau Server architecture supports fast and flexible deployments.

The following diagram shows Tableau Server’s architecture:



Tableau Server is internally managed by the multiple server processes.They are

1)Gateway/Load Balancer:-
It acts as an Entrygate to the Tableu Server and also balances the load to the Server if multiple Processes are configured.



2)Application Server:-

Application Server processes (wgserver.exe) handle browsing and permissions for the Tableau Server web and mobile interfaces. When a user opens a view in a client device, that user starts a session on Tableau Server. This means that an Application Server thread starts and checks the permissions for that user and that view.



3)Repository:-
Tableau Server Repository is a PostgreSQLdatabase that stores server data. This data includesinformation about Tableau Server users, groups and group assignments, permissions,projects,datasources, and extract metadata and refresh information.


4)VIZQL Server:-
Once a view is opened, the client sends a request to the VizQL process (vizqlserver.exe). The VizQL process then sends queries directly to the data source, returning a result set that is rendered as images and presented to the user. Each VizQL Server has its own cache that can be shared across multiple users

5)Data Engine:-
It Stores data  extracts and answers queries


6)Backgrounder:-
The backgrounder Executes server tasks which includes refreshes scheduled extracts,tasks initiated from tabcmd and manages other background tasks.


7)DataServer:-
DataServer Manages connections to Tableau Server data sources
It also maintains metadata from Tableau Desktop, such as calculations, definitions, and groups.



Thanks Guru's,
Prazval.ks




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