Error while creating persistanceVolume with mysql on kubernetes

First of all, using lastest mysql container you are using mysql:8.

--ignore-db-dir flag does not exist in version 8 so you should see in logs this error:

2020-09-21 0 [ERROR] [MY-000068] [Server] unknown option '--ignore-db-dir'.2020-09-21 0 [ERROR] [MY-010119] [Server] Aborting

After removing this flag, mysql stops crashing, but there appears to be other problem.

The hostPath volume does not work as expected. When I runned:

$ kubectl get pvcNAME             STATUS   VOLUME     CAPACITY   ACCESS MODES   STORAGECLASS   AGEmysql-pv-claim   Bound    pvc-xxxx   1Gi        RWO            standard       4m16s

you can see that STORAGECLASS is set to standard, and its causing k8s to provision a pv, instead of using already created one.

# kubectl get pvNAME            CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM                    STORAGECLASS   REASON   AGEpvc-xxxx        1Gi        RWO            Delete           Bound       default/mysql-pv-claim   standard                6m31stask-pv-volume  1Gi        RWO            Retain           Available                                                    6m31s

As you probably see the task-pv-volume status is Available and that means that nothing is using it.

To use it you you need to set storageClassName for Persistent Volume Claim to empty string: "" and maybe add volumeName like following:

apiVersion: v1kind: PersistentVolumeClaimmetadata:  name: mysql-pv-claim  labels:    app: mysql    tier: databasespec:  storageClassName: ""  volumeName: task-pv-volume  accessModes:    - ReadWriteOnce  resources:    requests:      storage: 1Gi

After doing this hostPath volume will work as expected, but there is still a problem with lost+found directory.

My solution would be to create another directory in /mnt/data/ dir e.g. /mnt/data/mysqldata/ and use /mnt/data/mysqldata/ as hostPath in PersistentVolume object.

Other solution would be using older version of mysql that supports --ignore-db-dir flag.