You are looking at the documentation of a prior release. To read the documentation of the latest release, please
visit here.
Backup and Restore MongoDB Sharded Clusters using Stash
Stash 0.9.0+ supports taking backup and restores MongoDB Sharded clusters in “idiomatic” way. This guide will show you how you can backup and restore your MongoDB Sharded clusters with Stash.
Before You Begin
- At first, you need to have a Kubernetes cluster, and the
kubectl
command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using Minikube. - Install KubeDB in your cluster following the steps here.
- Install Stash in your cluster following the steps here.
- Install Stash
kubectl
plugin following the steps here. - If you are not familiar with how Stash backup and restore MongoDB databases, please check the following guide here.
You have to be familiar with following custom resources:
To keep things isolated, we are going to use a separate namespace called demo
throughout this tutorial. Create demo
namespace if you haven’t created yet.
$ kubectl create ns demo
namespace/demo created
Backup Sharded MongoDB Cluster
This section will demonstrate how to backup MongoDB cluster. We are going to use KubeDB to deploy a sample database. Then, we are going to backup this database into a GCS bucket. Finally, we are going to restore the backed up data into another MongoDB cluster.
Deploy Sample MongoDB Sharding
Let’s deploy a sample MongoDB Sharding database and insert some data into it.
Create MongoDB CRD:
Below is the YAML of a sample MongoDB crd that we are going to create for this tutorial:
apiVersion: kubedb.com/v1
kind: MongoDB
metadata:
name: sample-mgo-sh
namespace: demo
spec:
version: 4.4.26
shardTopology:
configServer:
replicas: 3
storage:
resources:
requests:
storage: 1Gi
storageClassName: standard
mongos:
replicas: 2
shard:
replicas: 3
shards: 3
storage:
resources:
requests:
storage: 1Gi
storageClassName: standard
deletionPolicy: WipeOut
Create the above MongoDB
crd,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/mongodb/backup/logical/sharding/examples/mongodb-sharding.yaml
mongodb.kubedb.com/sample-mgo-sh created
KubeDB will deploy a MongoDB database according to the above specification. It will also create the necessary secrets and services to access the database.
Let’s check if the database is ready to use,
$ kubectl get mg -n demo sample-mgo-sh
NAME VERSION STATUS AGE
sample-mgo-sh 4.4.26 Ready 35m
The database is Ready
. Verify that KubeDB has created a Secret and a Service for this database using the following commands,
$ kubectl get secret -n demo -l=app.kubernetes.io/instance=sample-mgo-sh
NAME TYPE DATA AGE
sample-mgo-sh-auth Opaque 2 36m
sample-mgo-sh-cert Opaque 4 36m
$ kubectl get service -n demo -l=app.kubernetes.io/instance=sample-mgo-sh
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
sample-mgo-sh ClusterIP 10.107.11.117 <none> 27017/TCP 36m
sample-mgo-sh-configsvr-gvr ClusterIP None <none> 27017/TCP 36m
sample-mgo-sh-shard0-gvr ClusterIP None <none> 27017/TCP 36m
sample-mgo-sh-shard1-gvr ClusterIP None <none> 27017/TCP 36m
sample-mgo-sh-shard2-gvr ClusterIP None <none> 27017/TCP 36m
KubeDB creates an AppBinding crd that holds the necessary information to connect with the database.
Verify AppBinding:
Verify that the AppBinding
has been created successfully using the following command,
$ kubectl get appbindings -n demo
NAME AGE
sample-mgo-sh 30m
Let’s check the YAML of the above AppBinding
,
$ kubectl get appbindings -n demo sample-mgo-sh -o yaml
apiVersion: appcatalog.appscode.com/v1alpha1
kind: AppBinding
metadata:
annotations:
kubectl.kubernetes.io/last-applied-configuration: |
{"apiVersion":"kubedb.com/v1","kind":"MongoDB","metadata":{"annotations":{},"name":"sample-mgo-sh","namespace":"demo"},"spec":{"shardTopology":{"configServer":{"replicas":3,"storage":{"resources":{"requests":{"storage":"1Gi"}},"storageClassName":"standard"}},"mongos":{"replicas":2},"shard":{"replicas":3,"shards":3,"storage":{"resources":{"requests":{"storage":"1Gi"}},"storageClassName":"standard"}}},"deletionPolicy":"WipeOut","version":"4.4.26"}}
creationTimestamp: "2022-10-26T05:11:20Z"
generation: 1
labels:
app.kubernetes.io/component: database
app.kubernetes.io/instance: sample-mgo-sh
app.kubernetes.io/managed-by: kubedb.com
app.kubernetes.io/name: mongodbs.kubedb.com
name: sample-mgo-sh
namespace: demo
ownerReferences:
- apiVersion: kubedb.com/v1
blockOwnerDeletion: true
controller: true
kind: MongoDB
name: sample-mgo-sh
uid: 22f704c3-1a4d-468c-9404-7efa739ad0da
resourceVersion: "580483"
uid: 69092658-2f4a-45f2-a899-14884bf74a8b
spec:
appRef:
apiGroup: kubedb.com
kind: MongoDB
name: sample-mgo-sh
namespace: demo
clientConfig:
service:
name: sample-mgo-sh
port: 27017
scheme: mongodb
parameters:
apiVersion: config.kubedb.com/v1alpha1
configServer: cnfRepSet/sample-mgo-sh-configsvr-0.sample-mgo-sh-configsvr-pods.demo.svc:27017,sample-mgo-sh-configsvr-1.sample-mgo-sh-configsvr-pods.demo.svc:27017,sample-mgo-sh-configsvr-2.sample-mgo-sh-configsvr-pods.demo.svc:27017
kind: MongoConfiguration
replicaSets:
host-0: shard0/sample-mgo-sh-shard0-0.sample-mgo-sh-shard0-pods.demo.svc:27017,sample-mgo-sh-shard0-1.sample-mgo-sh-shard0-pods.demo.svc:27017,sample-mgo-sh-shard0-2.sample-mgo-sh-shard0-pods.demo.svc:27017
host-1: shard1/sample-mgo-sh-shard1-0.sample-mgo-sh-shard1-pods.demo.svc:27017,sample-mgo-sh-shard1-1.sample-mgo-sh-shard1-pods.demo.svc:27017,sample-mgo-sh-shard1-2.sample-mgo-sh-shard1-pods.demo.svc:27017
host-2: shard2/sample-mgo-sh-shard2-0.sample-mgo-sh-shard2-pods.demo.svc:27017,sample-mgo-sh-shard2-1.sample-mgo-sh-shard2-pods.demo.svc:27017,sample-mgo-sh-shard2-2.sample-mgo-sh-shard2-pods.demo.svc:27017
stash:
addon:
backupTask:
name: mongodb-backup-4.4.6
restoreTask:
name: mongodb-restore-4.4.6
secret:
name: sample-mgo-sh-auth
type: kubedb.com/mongodb
version: 4.4.26
Stash uses the AppBinding
crd to connect with the target database. It requires the following two fields to set in AppBinding’s Spec
section.
spec.appRef
refers to the underlying application.spec.clientConfig
defines how to communicate with the application.spec.clientConfig.service.name
specifies the name of the service that connects to the database.spec.secret
specifies the name of the secret that holds necessary credentials to access the database.spec.parameters.configServer
specifies the dsn of config server of mongodb sharding. The dsn includes the port no too.spec.parameters.replicaSets
contains the dsn of each replicaset of sharding. The DSNs are in key-value pair, where the keys are host-0, host-1 etc, and the values are DSN of each replicaset. If there is no sharding but only one replicaset, then ReplicaSets field contains only one key-value pair where the key is host-0 and the value is dsn of that replicaset.spec.parameters.stash
contains the Stash addon information that will be used to backup and restore this MongoDB.spec.type
specifies the types of the app that this AppBinding is pointing to. KubeDB generated AppBinding follows the following format:<app group>/<app resource type>
.
Insert Sample Data:
Now, we are going to exec into the database pod and create some sample data. At first, find out the database pod using the following command,
$ kubectl get pods -n demo --selector="mongodb.kubedb.com/node.mongos=sample-mgo-sh-mongos"
NAME READY STATUS RESTARTS AGE
sample-mgo-sh-mongos-9459cfc44-4jthd 1/1 Running 0 60m
sample-mgo-sh-mongos-9459cfc44-6d2st 1/1 Running 0 60m
Now, let’s exec into the pod and create a table,
$ export USER=$(kubectl get secrets -n demo sample-mgo-sh-auth -o jsonpath='{.data.\username}' | base64 -d)
$ export PASSWORD=$(kubectl get secrets -n demo sample-mgo-sh-auth -o jsonpath='{.data.\password}' | base64 -d)
$ kubectl exec -it -n demo sample-mgo-sh-mongos-9459cfc44-4jthd -- mongo admin -u $USER -p $PASSWORD
mongos> show dbs
admin 0.000GB
config 0.001GB
mongos> show users
{
"_id" : "admin.root",
"userId" : UUID("b9a1551b-83cf-4ebb-852b-dd23c890f301"),
"user" : "root",
"db" : "admin",
"roles" : [
{
"role" : "root",
"db" : "admin"
}
]
}
mongos> use newdb
switched to db newdb
mongos> db.movie.insert({"name":"batman"});
WriteResult({ "nInserted" : 1 })
mongos> db.movie.find().pretty()
{ "_id" : ObjectId("5d3064bf144a1b8fda04cd4f"), "name" : "batman" }
mongos> exit
bye
Now, we are ready to backup this sample database.
Prepare Backend
We are going to store our backed up data into a GCS bucket. At first, we need to create a secret with GCS credentials then we need to create a Repository
crd. If you want to use a different backend, please read the respective backend configuration doc from here.
Create Storage Secret:
Let’s create a secret called gcs-secret
with access credentials to our desired GCS bucket,
$ echo -n 'changeit' > RESTIC_PASSWORD
$ echo -n '<your-project-id>' > GOOGLE_PROJECT_ID
$ cat downloaded-sa-key.json > GOOGLE_SERVICE_ACCOUNT_JSON_KEY
$ kubectl create secret generic -n demo gcs-secret \
--from-file=./RESTIC_PASSWORD \
--from-file=./GOOGLE_PROJECT_ID \
--from-file=./GOOGLE_SERVICE_ACCOUNT_JSON_KEY
secret/gcs-secret created
Create Repository:
Now, crete a Repository
using this secret. Below is the YAML of Repository crd we are going to create,
apiVersion: stash.appscode.com/v1alpha1
kind: Repository
metadata:
name: gcs-repo-sharding
namespace: demo
spec:
backend:
gcs:
bucket: appscode-qa
prefix: demo/mongodb/sample-mgo-sh
storageSecretName: gcs-secret
Let’s create the Repository
we have shown above,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/mongodb/backup/logical/sharding/examples/repository-sharding.yaml
repository.stash.appscode.com/gcs-repo-sharding created
Now, we are ready to backup our database to our desired backend.
Backup MongoDB Sharding
We have to create a BackupConfiguration
targeting respective AppBinding crd of our desired database. Then Stash will create a CronJob to periodically backup the database.
Create BackupConfiguration:
Below is the YAML for BackupConfiguration
crd to backup the sample-mgo-sh
database we have deployed earlier.,
apiVersion: stash.appscode.com/v1beta1
kind: BackupConfiguration
metadata:
name: sample-mgo-sh-backup
namespace: demo
spec:
schedule: "*/5 * * * *"
repository:
name: gcs-repo-sharding
target:
ref:
apiVersion: appcatalog.appscode.com/v1alpha1
kind: AppBinding
name: sample-mgo-sh
retentionPolicy:
name: keep-last-5
keepLast: 5
prune: true
Here,
spec.schedule
specifies that we want to backup the database at 5 minutes interval.spec.target.ref
refers to theAppBinding
crd that was created forsample-mgo-sh
database.
Let’s create the BackupConfiguration
crd we have shown above,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/mongodb/backup/logical/sharding/examples/backupconfiguration-sharding.yaml
backupconfiguration.stash.appscode.com/sample-mgo-sh-backup created
Verify Backup Setup Successful:
If everything goes well, the phase of the BackupConfiguration
should be Ready
. The Ready
phase indicates that the backup setup is successful. Let’s verify the Phase
of the BackupConfiguration,
$ kubectl get backupconfiguration -n demo
NAME TASK SCHEDULE PAUSED PHASE AGE
sample-mgo-sh-backup mongodb-backup-4.4.6 */5 * * * * Ready 11s
Verify CronJob:
Stash will create a CronJob with the schedule specified in spec.schedule
field of BackupConfiguration
crd.
Verify that the CronJob has been created using the following command,
$ kubectl get cronjob -n demo
NAME SCHEDULE SUSPEND ACTIVE LAST SCHEDULE AGE
sample-mgo-sh-backup */5 * * * * False 0 <none> 13s
Wait for BackupSession:
The sample-mgo-sh-backup
CronJob will trigger a backup on each schedule by creating a BackupSession
crd.
Wait for the next schedule. Run the following command to watch BackupSession
crd,
$ kubectl get backupsession -n demo -w
NAME INVOKER-TYPE INVOKER-NAME PHASE AGE
sample-mgo-sh-backup-1563512707 BackupConfiguration sample-mgo-sh-backup Running 5m19s
sample-mgo-sh-backup-1563512707 BackupConfiguration sample-mgo-sh-backup Succeeded 5m45s
We can see above that the backup session has succeeded. Now, we are going to verify that the backed up data has been stored in the backend.
Verify Backup:
Once a backup is complete, Stash will update the respective Repository
crd to reflect the backup. Check that the repository gcs-repo-sharding
has been updated by the following command,
$ kubectl get repository -n demo gcs-repo-sharding
NAME INTEGRITY SIZE SNAPSHOT-COUNT LAST-SUCCESSFUL-BACKUP AGE
gcs-repo-sharding true 66.453 KiB 12 1m 20m
Now, if we navigate to the GCS bucket, we are going to see backed up data has been stored in demo/mongodb/sample-mgo-sh
directory as specified by spec.backend.gcs.prefix
field of Repository crd.
Note: Stash keeps all the backed up data encrypted. So, data in the backend will not make any sense until they are decrypted.
Restore MongoDB Sharding
You can restore your data into the same database you have backed up from or into a different database in the same cluster or a different cluster. In this section, we are going to show you how to restore in the same database which may be necessary when you have accidentally deleted any data from the running database.
Stop Taking Backup of the Old Database:
At first, let’s stop taking any further backup of the old database so that no backup is taken during restore process. We are going to pause the BackupConfiguration
crd that we had created to backup the sample-mgo-sh
database. Then, Stash will stop taking any further backup for this database.
Let’s pause the sample-mgo-sh-backup
BackupConfiguration,
$ kubectl patch backupconfiguration -n demo sample-mgo-sh-backup --type="merge" --patch='{"spec": {"paused": true}}'
backupconfiguration.stash.appscode.com/sample-mgo-sh-backup patched
Or you can use the Stash kubectl
plugin to pause the BackupConfiguration
,
$ kubectl stash pause backup -n demo --backupconfig=sample-mgo-sh-backup
BackupConfiguration demo/sample-mgo-sh-backup has been paused successfully.
Now, wait for a moment. Stash will pause the BackupConfiguration. Verify that the BackupConfiguration has been paused,
$ kubectl get backupconfiguration -n demo sample-mgo-sh-backup
NAME TASK SCHEDULE PAUSED PHASE AGE
sample-mgo-sh-backup mongodb-restore-4.4.6 */5 * * * * true Ready 26m
Notice the PAUSED
column. Value true
for this field means that the BackupConfiguration has been paused.
Simulate Disaster:
Now, let’s simulate an accidental deletion scenario. Here, we are going to exec into the database pod and delete the newdb
database we had created earlier.
$ kubectl exec -it -n demo sample-mgo-sh-mongos-9459cfc44-4jthd -- mongo admin -u $USER -p $PASSWORD
mongos> use newdb
switched to db newdb
mongos> db.dropDatabase()
{ "dropped" : "newdb", "ok" : 1 }
mongos> show dbs
admin 0.000GB
config 0.000GB
local 0.000GB
mongos> exit
bye
Create RestoreSession:
Now, we need to create a RestoreSession
crd pointing to the AppBinding of sample-mgo-sh
database.
Below is the YAML for the RestoreSession
crd that we are going to create to restore the backed up data.
apiVersion: stash.appscode.com/v1beta1
kind: RestoreSession
metadata:
name: sample-mgo-sh-restore
namespace: demo
spec:
repository:
name: gcs-repo-sharding
target:
ref:
apiVersion: appcatalog.appscode.com/v1alpha1
kind: AppBinding
name: sample-mgo-sh
rules:
- snapshots: [latest]
Here,
spec.repository.name
specifies theRepository
crd that holds the backend information where our backed up data has been stored.spec.target.ref
refers to the AppBinding crd for therestored-mgo-sh
database.spec.rules
specifies that we are restoring from the latest backup snapshot of the database.
Let’s create the RestoreSession
crd we have shown above,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/mongodb/backup/logical/sharding/examples/restoresession-sharding.yaml
restoresession.stash.appscode.com/sample-mgo-sh-restore created
Once, you have created the RestoreSession
crd, Stash will create a job to restore. We can watch the RestoreSession
phase to check if the restore process is succeeded or not.
Run the following command to watch RestoreSession
phase,
$ kubectl get restoresession -n demo sample-mgo-sh-restore -w
NAME REPOSITORY-NAME PHASE AGE
sample-mgo-sh-restore gcs-repo-sharding Running 5s
sample-mgo-sh-restore gcs-repo-sharding Succeeded 43s
So, we can see from the output of the above command that the restore process succeeded.
Verify Restored Data:
In this section, we are going to verify that the desired data has been restored successfully. We are going to connect to mongos
and check whether the table we had created earlier is restored or not.
Lets, exec into the database pod and list available tables,
$ kubectl exec -it -n demo sample-mgo-sh-mongos-9459cfc44-4jthd -- mongo admin -u $USER -p $PASSWORD
mongos> show dbs
admin 0.000GB
config 0.001GB
newdb 0.000GB
mongos> show users
{
"_id" : "admin.root",
"userId" : UUID("a57cb466-ec66-453b-b795-654169a0f035"),
"user" : "root",
"db" : "admin",
"roles" : [
{
"role" : "root",
"db" : "admin"
}
]
}
mongos> use newdb
switched to db newdb
mongos> db.movie.find().pretty()
{ "_id" : ObjectId("5d3064bf144a1b8fda04cd4f"), "name" : "batman" }
mongos> exit
bye
So, from the above output, we can see the database newdb
that we had created earlier is restored.
Backup MongoDB Sharded Cluster and Restore into a Standalone database
It is possible to take backup of a MongoDB Sharded Cluster and restore it into a standalone database, but user need to create the appbinding for this process.
Backup a sharded cluster
Keep all the fields of appbinding that is explained earlier in this guide, except spec.parameter
. Do not set spec.parameter.configServer
and spec.parameter.replicaSet
. By doing this, the job will use spec.clientConfig.service.name
as host, which is mongos
router DSN. So, the backup will treat this cluster as a standalone and will skip the idiomatic way
of taking backups of a sharded cluster. Then follow the rest of the procedure as described above.
apiVersion: appcatalog.appscode.com/v1alpha1
kind: AppBinding
metadata:
name: sample-mgo-sh-custom
namespace: demo
spec:
clientConfig:
service:
name: sample-mgo-sh
port: 27017
scheme: mongodb
secret:
name: sample-mgo-sh-auth
type: kubedb.com/mongodb
---
apiVersion: stash.appscode.com/v1alpha1
kind: Repository
metadata:
name: gcs-repo-custom
namespace: demo
spec:
backend:
gcs:
bucket: appscode-qa
prefix: demo/mongodb/sample-mgo-sh/standalone
storageSecretName: gcs-secret
---
apiVersion: stash.appscode.com/v1beta1
kind: BackupConfiguration
metadata:
name: sample-mgo-sh-backup2
namespace: demo
spec:
schedule: "*/5 * * * *"
task:
name: mongodb-backup-4.4.6
repository:
name: gcs-repo-custom
target:
ref:
apiVersion: appcatalog.appscode.com/v1alpha1
kind: AppBinding
name: sample-mgo-sh-custom
retentionPolicy:
name: keep-last-5
keepLast: 5
prune: true
This time, we have to provide Stash addon info in spec.task
section of BackupConfiguration
object as the AppBinding
we are creating manually does not have those info.
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/mongodb/backup/logical/sharding/examples/standalone-backup.yaml
appbinding.appcatalog.appscode.com/sample-mgo-sh-custom created
repository.stash.appscode.com/gcs-repo-custom created
backupconfiguration.stash.appscode.com/sample-mgo-sh-backup2 created
$ kubectl get backupsession -n demo
NAME BACKUPCONFIGURATION PHASE AGE
sample-mgo-sh-backup-1563528902 sample-mgo-sh-backup Succeeded 35s
$ kubectl get repository -n demo gcs-repo-custom
NAME INTEGRITY SIZE SNAPSHOT-COUNT LAST-SUCCESSFUL-BACKUP AGE
gcs-repo-custom true 22.160 KiB 4 1m 2m
Restore to a standalone database
No additional configuration is needed to restore the sharded cluster to a standalone database. Follow the normal procedure of restoring a MongoDB Database.
Standalone MongoDB,
apiVersion: kubedb.com/v1
kind: MongoDB
metadata:
name: restored-mongodb
namespace: demo
spec:
version: "4.4.26"
storageType: Durable
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
init:
waitForInitialRestore: true
deletionPolicy: WipeOut
This time, we have to provide spec.task
section in RestoreSession
object,
apiVersion: stash.appscode.com/v1beta1
kind: RestoreSession
metadata:
name: sample-mongodb-restore
namespace: demo
spec:
task:
name: mongodb-restore-4.4.6
repository:
name: gcs-repo-custom
target:
ref:
apiVersion: appcatalog.appscode.com/v1alpha1
kind: AppBinding
name: restored-mongodb
rules:
- snapshots: [latest]
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/mongodb/backup/logical/sharding/examples/restored-standalone.yaml
mongodb.kubedb.com/restored-mongodb created
$ kubectl get mg -n demo restored-mongodb
NAME VERSION STATUS AGE
restored-mongodb 4.4.26 Provisioning 56s
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/mongodb/backup/logical/sharding/examples/restoresession-standalone.yaml
restoresession.stash.appscode.com/sample-mongodb-restore created
$ kubectl get mg -n demo restored-mongodb
NAME VERSION STATUS AGE
restored-mongodb 4.4.26 Ready 56s
Now, exec into the database pod and list available tables,
$ export USER=$(kubectl get secrets -n demo restored-mongodb-auth -o jsonpath='{.data.\username}' | base64 -d)
$ export PASSWORD=$(kubectl get secrets -n demo restored-mongodb-auth -o jsonpath='{.data.\password}' | base64 -d)
$ kubectl exec -it -n demo restored-mongodb-0 -- mongo admin -u $USER -p $PASSWORD
> show dbs
admin 0.000GB
config 0.000GB
local 0.000GB
newdb 0.000GB
> show users
{
"_id" : "admin.root",
"userId" : UUID("98fa7511-2ae0-4466-bb2a-f9a7e17631ad"),
"user" : "root",
"db" : "admin",
"roles" : [
{
"role" : "root",
"db" : "admin"
}
]
}
> use newdb
switched to db newdb
> db.movie.find().pretty()
{ "_id" : ObjectId("5d3064bf144a1b8fda04cd4f"), "name" : "batman" }
> exit
bye
So, from the above output, we can see the database newdb
that we had created in the original database sample-mgo-sh
is restored in the restored database restored-mongodb
.
Cleanup
To cleanup the Kubernetes resources created by this tutorial, run:
kubectl delete -n demo restoresession sample-mgo-sh-restore sample-mongodb-restore
kubectl delete -n demo backupconfiguration sample-mgo-sh-backup sample-mgo-sh-backup2
kubectl delete -n demo mg sample-mgo-sh restored-mongodb
kubectl delete -n demo repository gcs-repo-sharding gcs-repo-custom