Stuck on OAuth token refresh failures during JMeter load test

Administration
1

Stuck on OAuth 2.0 token refresh failures when running a JMeter script with 200 concurrent users hitting /api/v2/users/me. The initial tokens work, but after 5 minutes, the API returns 401 Unauthorized for all subsequent requests, even though the refresh token endpoint is being called correctly. This seems to be a rate limit issue on the auth service during high-frequency token rotation.

Thanks for any help.

2

Ah, yeah, this is a known issue… The OAuth 2.0 refresh flow in Genesys Cloud enforces strict concurrency limits on the token endpoint. When 200 concurrent users attempt to refresh simultaneously, the auth service drops requests to prevent DoS conditions. The 401 errors are not due to invalid tokens but rather rate-limiting on the /v2/oauth/token endpoint. The solution involves staggering refresh requests and implementing exponential backoff in the JMeter script.

Use the Genesys Cloud CLI to verify current rate limits and configure the JMeter thread group to serialize token refreshes. Add a Timer element to introduce a random delay between refresh attempts:

<ConstantTimer guiclass="ConstantTimerGui" testclass="ConstantTimer" testname="Refresh Delay" enabled="true">
 <stringProp name="ConstantTimer.delay">1000</stringProp>
</ConstantTimer>

Additionally, implement a JSR223 PostProcessor to handle the refresh token logic with retry logic:

def responseCode = prev.getResponseCode()
if (responseCode == '401') {
 sampler.addArgument("grant_type", "refresh_token")
 sampler.addArgument("refresh_token", vars.get("refresh_token"))
 Thread.sleep(1000) // Exponential backoff
 return
}

This approach ensures that refresh requests are spaced out, preventing the auth service from hitting its concurrency threshold. The Genesys Cloud Terraform provider also includes examples of automated token management for CI/CD pipelines, which can be adapted for load testing scenarios. Verify the token expiration time in the Genesys Cloud admin console to ensure the refresh window aligns with the test duration.

3

if i remember correctly… this is just the auth service protecting itself. you need to stagger the refreshes in your script because simultaneous hits get blocked.