Defining the defaultMode in a Kubernetes volume field within a deployment element can become quite tricky.
It expects three decimals, corresponding to the binary UNIX permissions.
As an example, to mount the ConfigMap with permissions r------, you'd need to specify 256.
apiVersion: apps/v1
kind: Deployment
metadata:
name: foo
namespace: foo
spec:
replicas: 1
selector:
matchLabels:
app: foo
template:
metadata:
labels:
app: foo
spec:
containers:
- image: php-fpm:latest
volumeMounts:
- name: phpini
mountPath: /usr/local/etc/php/conf.d/99-settings.ini
readOnly: true
subPath: 99-settings.ini
volumes:
- configMap:
defaultMode: 256
name: phpini-configmap
optional: false
name: phpini
---
apiVersion: v1
kind: ConfigMap
metadata:
labels:
app: foo
namespace: foo
name: phpini-configmap
data:
99-settings.ini: |
; Enable Zend OPcache extension module
zend_extension = opcache