---
title:  Firewalls and Connections
---

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Be aware of possible connection problems that can result from running a firewall on your machine.

<%=vars.product_name_long%> is a network-centric distributed system, so if you have a firewall running on your machine it could cause connection problems. For example, your connections may fail if your firewall places restrictions on inbound or outbound permissions for Java-based sockets. You may need to modify your firewall configuration to permit traffic to Java applications running on your machine. The specific configuration depends on the firewall you are using.

As one example, firewalls may close connections to <%=vars.product_name%> due to timeout settings. If a firewall senses no activity in a certain time period, it may close a connection and open a new connection when activity resumes, which can cause some confusion about which connections you have.

For more information on how <%=vars.product_name%> client and servers connect, see the following topics:

-   [How Client/Server Connections Work](../../topologies_and_comm/topology_concepts/how_the_pool_manages_connections.html#how_the_pool_manages_connections)
-   [Socket Communication](../../managing/monitor_tune/socket_communication.html)
-   [Controlling Socket Use](../../managing/monitor_tune/performance_controls_controlling_socket_use.html#perf)
-   [Setting Socket Buffer Sizes](../../managing/monitor_tune/socket_communication_setting_socket_buffer_sizes.html)