---
title:  Discovering Locators Dynamically
---

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

However, if locator A (to which the client is connected) goes down before it discovers locator B, locator B is never discovered even though it is alive and the client receives a `NoLocatorsAvailable` exception.

One connection is attached to every application thread that is `local` to the respective thread. This is known as a thread local connection.

In this case, to perform any cache operation the client is not required to obtain a connection from pool. Instead the thread local connection of the client is used.

A thread local connection can be released by invoking the `Pool::releaseThreadLocalConnection()` method. The released connection is returned to the pool. If the number of threads is larger than the number of `max-connections`, the client throws an `AllConnectionsInUseException` after the `free-connection-timeout` lapses, unless the `Pool::releaseThreadLocalConnection()` method is used judiciously.

If a connection expires or the server goes down on which the connection was established, a thread local connection is immediately replaced with a good connection obtained from the pool.