Configurable app home directory base path

[DavidePrincipi]

NS8 modules (apps) are configured with the default distribution home directory base path, /home. For use cases where an alternative directory is required, the base path must be made configurable.

A configurable home directory base path is useful for placing application data on a different device if the default one is overloaded. The custom path can also be set before create-cluster is run or temporarily to place only a single app instance on an alternative disk.

Proposed solution

In the add-module action of a node, define a new node environment variable, HOME_BASEDIR, to run the underlying useradd command.

Alternative solutions

The storage requirements of an NS8 app come from persistent volumes and container images. Fine-grained bind-mounts for individual volumes can partially replace this feature.

See also

• https://mattermost.nethesis.it/nethesis/pl/ad59iu9h9bgbpbe5k8wdupjdta
• https://community.nethserver.org/t/ns8-growing-data-directories-path/21065/8?u=davidep

[DavidePrincipi]

In testing 3.4.2-dev.3

Test case 1

Check the correct command usage. Read instructions at https://nethserver.github.io/ns8-core/core/filesystem/#custom-base-path-for-home-directories and configure an alternative path as new home base directory.

Test case 2

Check the failure scenarios. The command must validate the home base directory according to these rules:

1. DIR must resolve to a filesytem path with no symlink components (validate_home_basedir).
2. DIR must be world-readable in all its path components (check_permissions).
3. DIR must be a device mountpoint. The device must not have other mountpoints (check_unique_mountpoint).

Ensure the exit code is non-zero if an error is found.

Note: --check can be used for failure checks.

[nrauso]

test case 1: VERIFIED
test case 2: VERIFIED

[DavidePrincipi]

Released https://github.com/NethServer/ns8-core/releases/tag/3.4.2