FAQ

JUICE module frequently asked questions.

Port Conflicts?

Multiple instances on the same node must use different port values. Example:

juice_instances:
  fs1:
    path: /fs1
    meta: postgres://...
    port: 9567
  fs2:
    path: /fs2
    meta: postgres://...
    port: 9568

Why does changing `data` not take effect?

Only juicefs format --no-update uses data. This setting does not change the filesystem after creation. To change the backend, migrate the data and reformat manually.

How to add a new instance?

Add instance definition in config
Run:

./juice.yml -l <host> -e fsname=<name>

How to remove an instance?

Set instance state to absent
Run:

./juice.yml -l <host> -t juice_clean,juice_register

Removal does not delete PostgreSQL metadata or object storage data. juice_register updates the target file. If you run only juice_clean, a stale monitoring scrape endpoint remains.

Where is file data stored?

Depends on data:

--storage postgres: JuiceFS creates a jfs_blob table in the PostgreSQL database selected by --bucket
--storage minio/s3: data is stored in a Silo/S3-compatible object-storage bucket

meta specifies the metadata engine. Pigsty production deployments usually use PostgreSQL for this role.

Multi-node mount notes?

Use the same meta and instance name on all nodes
Only one node needs to format the filesystem. Other nodes skip this operation.
Ensure port does not conflict on each node

Monitoring target not generated?

juice_register only writes /infra/targets/juice/ when infra group exists. You can run manually:

./juice.yml -l <host> -t juice_register

How to change mount options?

After you update mount in the instance, refresh the configuration. Then restart the service manually:

./juice.yml -l <host> -t juice_config,juice_launch
systemctl restart juicefs-<name>

FAQ