我正在关注Kubernetes教程:https://kubernetes.io/docs/tutorials/stateless-application/guestbook/#creating-the-redis-master-service
但是我不明白这句话。在前端部署中,有GET_HOSTS_FROM变量。其值为“ dns”。是进一步评估还是保留为“ dns”?
这是整个对应的Yaml:
#application/guestbook/frontend-deployment.yaml
apiVersion: apps/v1 # for versions before 1.9.0 use apps/v1beta2
kind: Deployment
metadata:
name: frontend
labels:
app: guestbook
spec:
selector:
matchLabels:
app: guestbook
tier: frontend
replicas: 3
template:
metadata:
labels:
app: guestbook
tier: frontend
spec:
containers:
- name: php-redis
image: gcr.io/google-samples/gb-frontend:v4
resources:
requests:
cpu: 100m
memory: 100Mi
env:
- name: GET_HOSTS_FROM
value: dns
# Using `GET_HOSTS_FROM=dns` requires your cluster to
# provide a dns service. As of Kubernetes 1.3,DNS is a built-in
# service launched automatically. However,if the cluster you are using
# does not have a built-in DNS service,you can instead
# access an environment variable to find the master
# service's host. To do so,comment out the 'value: dns' line above,and
# uncomment the line below:
# value: env
ports:
- containerPort: 80