FAQ

JUICE module frequently asked questions.

Reference

JUICE

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?

data is only used by juicefs format --no-update. After filesystem creation it will not change. To switch backend, migrate 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 refreshes the target file; running only juice_clean leaves a stale monitoring scrape endpoint.

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

Metadata is stored in the metadata engine defined by meta (in Pigsty production scenarios, this is usually PostgreSQL).

Multi-node mount notes?

Use the same meta and instance name on all nodes
Only one node needs to format; others will skip
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 updating mount in the instance, refresh config first and then manually restart the service:

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

FAQ