---
title:  How Client Load Balancing Works
---

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In a distributed system, servers can be added or removed and their capacity to service new client connections may vary. The server connectivity options are specified in the connection pool configuration.

The connection pool API supports connecting to servers through server locators or directly connecting to servers.

-   **[Server Locators](about-server-locators.html)**

    Server locators continuously monitor server availability and server load information. The client is configured with a list of server locators and consults a server locator to request a connection to a server in the distributed system.

-   **[Connection Pools](about-connection-pools.html)**

    Clients contain connection pools. Each region is associated with a connection pool using a region attribute, and operations on the region use connections from the respective pools.

-   **[Discovering Locators Dynamically](discovering-locators-dynamically.html)**

    A background thread periodically queries the locator for any other locators joining the distributed system.