Apache Geode

Firewalls and Ports

Make sure your port settings are configured correctly for firewalls.

There are several different port settings that need to be considered when using firewalls:

• Port that the cache server listens on. This is configurable using the cache-server element in cache.xml, on the CacheServer class in Java APIs, and as a command line option to the gfsh start server command.

  By default, if not otherwise specified, Geode clients and servers discover each other on a pre-defined port (40404) on the localhost.

• Locator port. Geode clients can use the locator to automatically discover cache servers. The locator port is configurable as a command-line option to the gfsh start locator command. Locators are used in the peer-to-peer cache deployments to discover other processes. They can be used by clients to locate servers as an alternative to configuring clients with a collection of server addresses and ports.

  By default, if not otherwise specified, Geode locators use the default port 10334.

• Since locators start up the cluster, locators must also have their ephemeral port range and TCP port accessible to other members through the firewall.

• For clients, you configure the client to connect to servers using the client’s pool configuration. The client’s pool configuration has two options: you can create a pool with either a list of server elements or a list of locator elements. For each element, you specify the host and port. The ports specified must be made accessible through your firewall.

Limiting Ephemeral Ports for Peer-to-Peer Membership

By default, Geode assigns ephemeral ports, that is, temporary ports assigned from a designated range, which can encompass a large number of possible ports. When a firewall is present, the ephemeral port range usually must be limited to a much smaller number, for example six. If you are configuring P2P communications through a firewall, you must also set the TCP port for each process and ensure that UDP traffic is allowed through the firewall.

Properties for Firewall and Port Configuration

This table contains properties potentially involved in firewall behavior, with a brief description of each property.

Default Port Configurations

Properties for Firewall and Port Configuration in Multi-Site (WAN) Configurations

Each gateway receiver uses a single port to accept connections from gateway senders in other systems. The configuration of a gateway receiver specifies a range of possible port values to use. Geode selects an available port from the specified range when the gateway receiver starts. Configure your firewall so that the full range of possible port values is accessible by gateway senders from across the WAN.