# oc new-project test

# cat redis-config
maxmemory 2mb
maxmemory-policy allkeys-lru

# oc create configmap test-redis-config --from-file=redis-config
configmap/test-redis-config created

# oc get configmap test-redis-config -o yaml
apiVersion: v1
data:
  redis-config: |
    maxmemory 2mb
    maxmemory-policy allkeys-lru
kind: ConfigMap
metadata:
  creationTimestamp: 2018-12-04T10:34:25Z
  name: test-redis-config
  namespace: test
  resourceVersion: "1900458"
  selfLink: /api/v1/namespaces/test/configmaps/test-redis-config
  uid: 2c08ecdc-f7b0-11e8-9a57-001a4a160173

apiVersion: v1
kind: Pod
metadata:
  name: redis
spec:
  containers:
  - name: redis
    image: kubernetes/redis:v1
    env:
    - name: MASTER
      value: "true"
    ports:
    - containerPort: 6379
    resources:
      limits:
        cpu: "0.1"
    volumeMounts:
    - mountPath: /redis-master-data
      name: data
    - mountPath: /redis-master
      name: config
  volumes:
    - name: data
      emptyDir: {}
    - name: config
      configMap:
        name: test-redis-config
        items:
        - key: redis-config
          path: redis.conf

# oc apply -f redis-pod.yaml

# oc exec -it redis redis-cli
127.0.0.1:6379> CONFIG GET maxmemory
1) "maxmemory"
2) "2097152"
127.0.0.1:6379> CONFIG GET maxmemory-policy
1) "maxmemory-policy"
2) "allkeys-lru"