Performance Testing:Common errors and solutions

class java.net.ConnectException:null

Cause: The TCP connection to the target server failed or was rejected.

Solution: Check the backend server health and verify that no network bottleneck exists between PTS and the target.

org.apache.http.ConnectionClosedException:Connection closed

Cause: The server terminated the connection abnormally.

Solution: Check the backend server logs for errors or resource exhaustion that could cause abrupt disconnections.

org.apache.hc.core5.http.ConnectionClosedException:Connection is closed

Cause: PTS sent a request on a connection that the server had already closed.

Solution: Check whether the gateway-layer bandwidth or network path has a bottleneck. If the server is behind a load balancer, verify that idle-connection timeout settings are aligned between PTS and the load balancer.

java.io.IOException:Connection reset by peer

Cause: The backend server forcibly reset the connection.

Solution: If Server Load Balancer (SLB) is in the request path, check the SLB listener configuration, particularly the connection timeout and health check settings.

org.apache.http.ConnectionClosedException:Connection closed unexpectedly

Cause: The connection was terminated before PTS received the response. Typical triggers include:

• The server failed to respond within the expected timeframe.

• The debug session or stress test was stopped before the response arrived.

Solution: Verify that the server can handle the request within the configured timeout. If the test was intentionally stopped, this error is expected and can be ignored.

java.util.concurrent.TimeoutException:null

Cause: The TCP connection attempt timed out. PTS could not reach the target server within the allotted time.

Solution:

1. Use the timing waterfall flow in the sampling log details to check whether the connection phase takes unusually long. For details, see Analyze stress testing results.

2. Check the backend server health and network path for bottlenecks.

org.apache.hc.core5.http2.H2StreamResetException:Timeout due to inactivity (5000 MILLISECONDS) * class

Cause: The backend server did not respond within the default request timeout of 5 seconds.

Solution: Extend the request timeout in the Advanced Settings section of the Create Scenario page.

java.net.SocketTimeoutException:null

Cause: The request timed out while waiting for a response or while reading data (idle timeout).

Solution:

1. Verify that the server is healthy and can process requests within the expected time.

2. Check whether the stress testing API has an appropriate timeout setting.

3. Investigate the server for performance bottlenecks (CPU, memory, I/O).

java.lang.RuntimeException:java.net.UnknownHostException

Cause: The domain name cannot be resolved.

Solution:

1. Verify that the domain name is registered and resolves correctly.

2. If the domain is not registered with a public DNS, bind it in PTS before running the test.

org.apache.http.client.CircularRedirectException

Cause: The request entered a redirect loop (for example, A -> B -> C -> A) or exceeded 10 redirects.

Solution:

1. Disable 302 redirect: On the Scenario Settings page, turn off the Allow 302 Redirect switch.

   

2. Run the stress test again and inspect the original request to confirm the redirect chain.

3. To see the exact redirect path, open the sampling log details in the stress testing report and check the timing waterfall flow. For details, see Analyze stress testing results.

org.apache.hc.core5.http.ProtocolException:Header 'key: value' is illegal for HTTP/2 messages

Cause: The scenario includes headers that HTTP/2 does not allow. The following headers are prohibited in HTTP/2: Connection, Keep-Alive, Proxy-Connection, Transfer-Encoding, Host, and Upgrade.

Solution: Remove the unsupported headers from the scenario configuration and rerun the test.

java.nio.channels.CancelledKeyException:null

Cause: The backend server terminated the connection under the HTTP/2 protocol.

Solution: Investigate the backend server logs for HTTP/2-specific issues such as stream resets or GOAWAY frames.

java.lang.RuntimeException: Could not find the TestPlan class!

Cause: The JMeter script was created with a version that is not compatible with JMeter V5.0.

Solution: Open and re-save the script in JMeter V5.0, then upload it to PTS again.

java.lang.SecurityException: class "xxx"'s signer information does not match signer information of other classes in the same package

Cause: The Java sampler dependency (ApacheJMeter_core or ApacheJMeter_java) in the script was built against a JMeter version other than V5.0.

Solution: Repackage the dependency JAR using JMeter V5.0 libraries and upload the updated package.

Attempt to resolve method: xxx() on undefined variable or class name:

Cause: The BeanShell sampler references a class that was not uploaded with the script.

Solution: Upload the missing JAR package that contains the required class and rerun the test.

class java.lang.IllegalArgumentException:forbidden uri, uri host must match vpc cidr pattern 10.0.0.0/8, 172.16.0.0/12 or 192.168.0.0/16

Cause: The stress test is configured to use a VPC, but the domain name in the test URL resolves to a public IP address instead of an internal IP address. VPC stress tests require that the target IP falls within a private CIDR range (10.0.0.0/8, 172.16.0.0/12, or 192.168.0.0/16).

Solution: Either of the following approaches works:

• Use an internal IP address directly in the test URL.

• Log on to the PTS console and bind the domain name to an internal IP address.

403 (Forbidden)

A 403 response means the server received the request but refused to authorize it. Common causes in PTS stress tests:

<html>
<head>
<meta http-equiv="Content-Type" content="textml;charset=UTF-8" />
   <style>body{background-color:#FFFFFF}</style>
<title>TestPage184</title>
  <script language="javascript" type="text/javascript">
         window.onload = function () {
           document.getElementById("mainFrame").src= "http://****.aliyun.com/alww.html";
            }
</script>
</head>
  <body>
    <iframe style="width:860px; height:500px;position:absolute;margin-left:-430px;margin-top:-250px;top:50%;left:50%;" id="mainFrame" src="" frameborder="0" scrolling="no"></iframe>
    </body>
</html>

405 (Method Not Allowed)

A 405 response means the server does not support the HTTP method used in the request. Common causes in PTS:

1. 302 redirect changes the request method. When a POST request triggers a 302 redirect, the HTTP client may convert it to a GET request. If the target endpoint does not accept GET, a 405 error is returned.

2. The server explicitly restricts methods. Check the response Allow header (for example, Allow=GET) to see which methods the server accepts.

3. SLB or web server forwarding modifies the method. When a load balancer or reverse proxy forwards the request, the method may be changed. Verify the forwarding rules.

406 (Not Acceptable)

A 406 response means the server cannot produce a response that matches the Accept header in the request.

Cause: The Accept value on the Header Definition tab does not match the content type that the server can return. This typically happens when the Content-Type on the Body Definition tab is automatically synced to the Header Definition tab, and the Accept value conflicts with it.

Solution: Adjust the Accept header to match a type the server supports. Test different values to determine which types the server accepts. The following table lists common Accept formats and their matching order.

Matching priority: When multiple Accept types are specified, the server matches them in this order:

• No quality factor: Matched left to right. application/xml, text/html, application/json matches as application/xml > text/html > application/json.

• With quality factor: Higher q values take priority. application/xml;q=0.3, application/json;q=0.8, text/html (defaults to q=1.0) matches as text/html > application/json > application/xml.

• Wildcard specificity: More specific types match first. */*, text/*, text/html matches as text/html > text/* > */*.

503 (Service Unavailable)

504 (BadGateway Timeout)

Cause: The gateway did not receive a timely response from the backend server.

Solution:

1. Verify that the backend server is running and processing requests normally.

2. Extend the timeout period at the gateway layer.

3. Extend the request timeout in the Advanced Settings section of the Create Scenario page to give the load generator more time.