Selenium WebDriverException: Session [null] not available and is not among the last 1000 terminated sessions

Question

I am getting the below WebDriver exception when trying to navigate to a URL (just simply to Google) using Selenium Grid running locally.

org.openqa.selenium.WebDriverException: Session [null] not available and is not among the last 1000 terminated sessions.

I am running selenium-server-standalone-3.141.59.jar on my desktop in the Grid configuration with one hub and one node. In two different cmd windows I start the hub with -role hub, and then the node with -role node -hub http://localhost:4444/grid/register. All seems to start just fine.

Java code:

public void initialGridTest() throws Exception {
    try {
        System.setProperty("webdriver.chrome.driver", "D:\\SeleniumWebDrivers\\chromedriver.exe");
        DesiredCapabilities capability = DesiredCapabilities.chrome();
        RemoteWebDriver driver = new RemoteWebDriver(new URL("http://localhost:4444/wd/hub"), capability);

        driver.get("http://www.google.com");
        String doodleText = driver.findElement(By.id("logo-doodle-image")).getText();
    } catch (Exception e) {
        System.out.println("e: " + e);
    }
}

I have a simple test in a Java class running in IntelliJ that calls RemoteWebDriver to navigate to Google. When I execute new RemoteWebDriver(... in the code, I see my Java program connecting to the hub and the hub connecting with the node, and the node opens a new instance of Chrome. But when the program runs driver.get() I get the WebDriverException. I see in the node console that it has a session id, but for some reason the session is null in my Java code.

SOLVED! ended up being the fact that I was running selenium-server-standalone-3.141.59.jar for my Grid hub and node, but the pom.xml for my Java code in IntelliJ was pulling Selenium version 2.53.0. Just emphasized the importance of keeping all of the individual versions of all the different Selenium parts (server jar, Java code, browser drivers, etc.) all synced up! Is there are spreadsheet out there somewhere that defines all that? — John S, Aug 13 '19 at 22:13

score 3 · Answer 1 · answered Aug 14 '19 at 16:51

This error message...

org.openqa.selenium.WebDriverException: Session [null] not available and is not among the last 1000 terminated sessions.

...implies that the Selenium Grid Node was unable to communicate with the Selenium Grid Hub.

As per the following discussions:

It seems this error stems out when:

Selenium Grid Hub, Selenium Grid Node and the Client Process are initiated/spawned from different versions of Selenium client.

Solution

Ensure that Selenium Grid Hub, Selenium Grid Node and the Client Process all of them uses the same version of Selenium client i.e. Selenium v3.141.59

Selenium WebDriverException: Session [null] not available and is not among the last 1000 terminated sessions

1 Answers1

Solution