Fix Error 413 Request Entity Too Large on K3s Nginx Ingress

Recently I have installed SonarQube Community Edition on my lab for research purposes, and been trying to integrate it with Jenkins pipelines. The scenario is the following:

• I’m running Jenkins on a Windows Server 2022 Datacenter Azure Edition, on an Azure Virtual Machine
• I have a K3s node installed on a separate Azure Virtual Machine that is running Ubuntu 22.04
• On the K3s node, I’m running an instance of SonarQube Community Edition

The problem in this case is that everytime I run the analysis, it seems to complete it but fails when trying to upload it to the SonarQube server. The error that the console outputs says “413 Request Entity Too Large”. It seems that is a problem with nginx as I can see the nginx name on the html response body.

After some research on Internet, I have found that I need to add the nginx.ingress.kubernetes.io/proxy-body-size annotation with the 0 value:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: sonarqube
  namespace: sonarqube
  labels:
    app: sonarqube
  annotations:
    nginx.ingress.kubernetes.io/proxy-body-size: "0"
spec:
  [...]

By giving it a value of 0, I put no restrictions on the size of the data that can be sent to the server. Problem is, in my case is still failing with the same error. After some thinking I came to the conclusion that maybe something can be configured on the Nginx Ingress side, and looking through the documentation I found another parameter named client-max-body-size that can be added to the configmap of the Nginx Ingress:

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-ingress
  namespace: nginx-ingress
  [...]
data:
  client-max-body-size: "50m"

With this setting, I allow requests of a maximum of 50 MB, of course this setting can be adjusted to meet our needs. After saving the changes I tried running the pipeline again and the report uploaded successfully to the server.

It took me some time, specially this last bit on the Nginx Ingress configmap, so I’m writing this post in case anybody has the same problem, and for if I ever have this problem again.