how to write data outside a container?

Question

hope some of you may have a solution to this :

I have a python code that is supposed to write a file output.csv, I want to find that file outside the container in a folder named /data, I have a glusterfs volumes. so I'm using Kubernetes to deploy my container. then when it runs I should find that file in the folder of the glusterfs: here is my Yaml file : the glusterfs volume :

[xxx@xxxx ~]$ df |grep gluster
/dev/mapper/glustervg-glusterlv    10471424  1633164    8838260  16% /var/lib/glusterfs
xxxx:/gluster_vol             10471424  1737876    8733548  17% /data

thank you for your help

update: I've followed this tutorial to try to deploy a volume with glusterfs https://docs.openshift.com/container-platform/3.7/install_config/storage_examples/gluster_example.html

so I created these file : gluster endpoit.yaml

apiVersion: v1
kind: Endpoints
metadata:
  name: gluster-cluster
subsets:
- addresses:
  - ip: 10.122.5.143
  ports:
  - port: 1
    protocol: TCP
- addresses:
  - ip: 10.122.5.142
  ports:
  - port: 1
    protocol: TCP

the persistent volume:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: gluster-pv
spec:
  capacity:
    storage: 3Gi
  accessModes:
  - ReadWriteMany
  glusterfs:
    endpoints: gluster-cluster
    path: data
    readOnly: false
  persistentVolumeReclaimPolicy: Retain

the persistent volume claim :

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: gluster-claim
spec:
  accessModes:
  - ReadWriteMany
  resources:
     requests:
       storage: 3Gi

the gluster service :

apiVersion: v1
kind: Service
metadata:
  name: gluster-cluster
spec:
  ports:
  - port: 

and my new deployment looks like this :

apiVersion: apps/v1
kind: Deployment
metadata:
  name: uc1-deploy
spec:
  selector:
    matchLabels:
      app: uc1
  replicas: 1
  template:
    metadata:
      labels:
        app: uc1
    spec:
      containers:
      - name: uc1
        image: predicteur_uc1:1.5
        volumeMounts:
        - mountPath: /output
          name: test-volumed
          readOnly: false
        ports:
        - containerPort: 90
      volumes:
      - name: test-volumed
        persistentVolumeClaim:
          claimName: gluster-claim

and when I deploy it I get that error :

Output: Running scope as unit run-20456.scope.
[2019-11-25 11:29:08.230125] E [glusterfsd.c:825:gf_remember_backup_volfile_server] 0-glusterfs: failed to set volfile server: File exists
Mount failed. Please check the log file for more details.
, the following error information was pulled from the glusterfs log to help diagnose this issue:
[2019-11-25 11:29:08.244765] E [glusterfsd-mgmt.c:1958:mgmt_getspec_cbk] 0-glusterfs: failed to get the 'volume file' from server
[2019-11-25 11:29:08.244841] E [glusterfsd-mgmt.c:2151:mgmt_getspec_cbk] 0-mgmt: failed to fetch volume file (key:/data)

Answer 1

YES the value must be gluster_vol instead of data wich data represent the folder where the glusterfs is mounted on the machine but the volume name is rather gluster_vol. that is the fisrt error I made.

second the mountpath in the deployment represent a folder inside the container where my gluster_vol ( and what it containes) must be mounted so it create a folder inside the container that is linked to the gluster vol, so basicaly i will put whatever is on the gluster_vol inside the folder output wich is inside my container.

third my python code crate the csv files inside the folder output/opportunity, so this folder structure must be in the gluster_vol too . thank you helloWorld and clement for your implication guys, you helped