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Storage and Backup Updated 2026-05-27

External NFS storage

Mounting an NFS share from a third-party storage server into your PaaS environment, without copying data onto the platform.

When you already have an NFS-capable storage system — a NAS appliance, an off-platform Linux box, another PaaS region exporting data — you do not need to copy the data onto Stack Harbor PaaS to use it. The platform can mount that existing share directly into a container, on the same operating model as a local storage container.

When to use external NFS

This option fits when:

  • The data lives on a system you already operate and you want to keep it there.
  • Several PaaS installations need access to the same dataset and you want a single source.
  • A third-party service produces or consumes the data and you do not want to maintain a copy in two places.
  • Your organization’s policy keeps certain data on specific infrastructure.

If, on the other hand, you are planning to set up a high-performance, reliable storage layer from scratch, prefer a dedicated Shared Storage Container — it ships with the storage software preinstalled and integrates with the platform’s exports and mount-points UI without extra work.

How the mount works

External NFS mounts are configured from the client container, not from the storage side (which is out of the platform’s control). On the client:

  • Open the configuration manager, switch to Mount Points, and click Mount.
  • Pick External Server as the operation type.
  • Provide the NFS server’s IP or domain, the remote path to mount, and the local mount point.

The platform installs the NFS client tooling on the container if it is not already present (a one-time delay), creates the mount point if the local directory does not exist, and writes the mount entry so it persists across container restarts.

Requirements on the server side

You manage these yourself, because the server is outside the platform:

  • NFS server software running (NFSv3 supported on all certified containers, NFSv4 client supported on all containers, NFSv4 server only on the Shared Storage Container).
  • The directories you want to share declared in /etc/exports with the appropriate client IPs and permission flags.
  • NFS ports (111, 2049, 20048) reachable from the PaaS environment’s egress IP.
  • Unix ownership on the exported folder that matches what the client process expects. If the client runs as jelastic and the folder is root:root, writes will fail.

Permission considerations

External NFS does not give you the platform’s automatic permission wiring. You need to:

  • Decide whether the share is read-only or read-write on the server side (the ro / rw flag in the exports file).
  • Make sure the UID/GID inside the client container has matching permissions on the server’s filesystem.
  • Open the firewall on the server for the platform’s source IP. The platform’s container can reach out from a stable egress IP if the environment has a public IP attached.

Where to go from here

  • Mount points — the dialog used to add the external mount.
  • Configure external NFS server — what the server side needs to look like if you operate it yourself.
  • NFS — protocol-level notes that apply to both internal and external NFS.