[Bug]: slow-start config defined in virtualserverroute seems not work

[MinbinLuo]

Version

edge

What Kubernetes platforms are you running on?

Kind

Steps to reproduce

I tried to set up slow start in my virtualserverroute defination but it seems the nginx does not respect it:

  upstreams:
    - name: my-service
      service: my-service
      port: 9000
      keepalive: 64
      connect-timeout: 10s
      read-timeout: 30s
      send-timeout: 30s
      next-upstream-tries: 1
      fail-timeout: 15s
      max-fails: 1
      lb-method: least_conn
      slow-start: 45s
      healthCheck:
        enable: true
        path: /alive
        port: 8558
        interval: 5s
        passes: 1
        fails: 3
        mandatory: true

I tried to use lb-method:round_robin and removed healthCheck and set mandatory to false, but it all did not work

claude said that:

The actual problem is that slow-start requires a server state transition (down→up), but new endpoints appear already "up". Whether the controller uses API calls or config reloads, the result is the same - no transition, no slow-start.

is that correct?

[github-actions]

Hi @MinbinLuo thanks for reporting!

Be sure to check out the docs and the Contributing Guidelines while you wait for a human to take a look at this 🙂

Cheers!

[MinbinLuo]

Is it because the default weight is 1, and since the weight doesn’t accept decimals, it just becomes 1 directly?

[AlexFenlon]

Hi @MinbinLuo ,

what version of NGINX Ingress Controller are you running?

Did you use our doc to get this set up or did Claude AI help you with this?

[MinbinLuo]

Hi @AlexFenlon, out infra team set up it for me

nginx -v
nginx version: nginx/1.27.4 (nginx-plus-r34-p1)

[AlexFenlon]

That is the nginx version. not the NGINX Ingress Controller version.

Are you able to check the top of the logs to see if the version is there?

[MinbinLuo]

the NGINX Ingress Controller version is app.kubernetes.io/version: 5.0.0

[AlexFenlon]

Okay great, thank you. @MinbinLuo

Are you able to run a kubectl get vsr -A then kubectl describe vsr <name of vsr> -n <namespace> and tell me the events at the bottom of that?

[MinbinLuo]

There are no events:
Events:

[MinbinLuo]

[AlexFenlon]

Thanks @MinbinLuo ,

Will talk with the team and respond soon.

[AlexFenlon]

HI @MinbinLuo,

Can you please provide the name and logs of the virtual server route?

Can you also provide contents of the configuration file inside the etc/nginx/conf.d/ folder.