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In JVMs running the latest version of Geode, `AvailablePort` and `AvailablePortHelper`  AvailablePort and AvailablePortHelper will choose random ports from these assigned ranges. As a result, no two well-behaved tests will ever try to bind to the same port, no matter how many are running concurrently.

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• To assign an available port, call `AvailablePortHelper` or `AvailablePort` AvailablePortHelper or AvailablePort. These are the only classes that know about the reduced port range for the test.
• Call `AvailablePort` and `AvailablePortHelper` Call AvailablePort and AvailablePortHelper only in the current version of Geode. Do not call these classes in Child VMs running older versions of Geode. Older versions of Geode do not honor the new, reduced port ranges.
• Do not launch any service using Geode’s default port for that service. Always explicitly assign an available port. The only safe use of default ports is in a test to verify that a service uses its default port by default.
• Do not launch any service using a port number hard-coded into the test. Always explicitly assign an available port. There is no safe use of any hard-coded port number in tests that can run concurrently.

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