openstack-help

Display a description of a particular command

$ openstack help [command_name]

$ openstack --os-identity-api-version 3 --help

$ openstack --help

openstack help
openstack help [command]
openstack [command] --help

command
    Specifies the particular OpenStack CLI command for which help is requested. This can be a service name (e.g., server) or a full command path (e.g., server create).

--help
    A standard option available for any openstack command. When appended, it displays a detailed usage message, including options and arguments specific to that command, and then exits.

The term openstack-help typically refers to the mechanism for accessing documentation and usage information within the official OpenStack Command Line Interface (CLI). While openstack-help is not a standalone binary or command in most standard OpenStackClient installations, it conceptualizes the essential functionality provided by the openstack help subcommand or the --help option.

The openstack help subcommand provides a top-level list of available services and commands, or detailed assistance for a specific subcommand. For instance, openstack help server will display information about the server commands. Additionally, the --help option can be appended to any openstack command to show its specific usage, options, and arguments. For example, openstack server create --help reveals all parameters for creating a new server instance. This system is crucial for users to discover capabilities and understand command syntax without needing to consult external documentation.

`openstack-help` is not a standard executable binary delivered with the OpenStackClient. It generally refers to the help functionality provided by the openstack client itself, predominantly through the openstack help subcommand and the --help flag. Some distributions or custom environments might include a shell script named `openstack-help` as a wrapper or alias, but its underlying function relies on the core openstack client's help system.

While not directly parameters of the help function, openstack commands, including openstack help, can be prefixed with various global options that affect how the client connects and interacts with OpenStack. Common global options include --os-cloud, --debug, --verbose, --json, etc. These options typically precede the command and its arguments.

It's important to distinguish between openstack help [command] and openstack [command] --help. The former provides a general overview or lists subcommands for a given command/service. The latter, --help, offers very specific, detailed information about the direct usage, arguments, and options for the command it's appended to. For example, openstack help server create might show less detail than openstack server create --help.

The integrated help system has been a fundamental part of the OpenStack Command Line Interface (CLI) since its inception. Early versions of the CLI (often separate clients like `nova client`, `glance client`, etc., before the unified openstack client) also provided --help options. With the advent of the unified openstack client, the help subcommand was introduced to consolidate and standardize access to documentation across all services, making it a central and easily discoverable feature for users interacting with OpenStack from the command line. Its continuous development focuses on providing up-to-date and comprehensive usage information as the OpenStack services evolve.

openstack(1), man(1), info(1)