sidercar-configmap namesapces must equal with k8s-sidecar-injector-prod namespace

[zhangjianweibj]

i run injector with help of deployment.md
yaml files is in project example directory.every thing is ok,then i run a diferent instances.
pod yaml file:

apiVersion: v1
kind: Pod
metadata:
  name: debian-debug
  namespace: monitoring
  annotations:
    injector.tumblr.com/request: sidecar-telegraf-basic
spec:
  containers:
  - image: debian:jessie
    command: ["/bin/sh"]
    args: ["-c", "while true; do echo hello; sleep 10; done"]
    imagePullPolicy: IfNotPresent
    name: debian-debug
    resources:
      requests:
        memory: "200M"
        cpu: "500m"
  restartPolicy: Never

sidecar config file:

k8s-sidecar-injector logs show " requested injection sidecar-telegraf-basic was not in configuration".

then i modify sidecar config file.modify namespaces which is equal with k8s-sidecar-injector's namespace.

and it works.

why??in my opinion,the target pods which namespace is monitoring, k8s-sidecar-injector should use sidecar config which namespace is monitirng.not kube-system.

[byxorna]

As written, the sidecar injector watches ConfigMaps in a specific namespace. This is controllable via --configmap-namespace (see https://github.com/tumblr/k8s-sidecar-injector/blob/master/internal/pkg/config/watcher/watcher.go#L46). As I designed it, I thought of the Sidecar ConfigMaps as being associated with the injector, not the pods that request the injection. For this reason, it makes sense that the ConfigMaps must live in the namespace where the k8s-sidecar-injector runs, not where an arbitrary pod runs.

[zhangjianweibj]

ok。very thanks