private void startServer(String name) throws IOException {
    Path dir = createDirectories(rootFolder.resolve(name));

    int[] availablePorts = getRandomAvailableTCPPorts(1);
    int port = availablePorts[0];

    String locatorString = "localhost[" + locatorPort + "]";

    String startServerCommand = String.join(" ",
        "start server",
        "--name=" + name,
        "--dir=" + dir,
        "--bind-address=127.0.0.1",
        "--server-port=" + port,
        "--locators=" + locatorString,
        "--security-properties-file=" + clusterSecurityProperties);

    gfshRule.execute(startServerCommand);
  }
This test verifies that rotating to an untrusted certificate causes an exception when the
client tries to form a new secure connection. This is a sanity check that certificates are
being dynamically updated.
geode-assembly/src/acceptanceTest/java/org/apache/geode/ssl/CertificateRotationTest.java