Glossary and Reference
This section defines common terms and concepts used within Exosphere.
- Host
A host is a remote system that Exosphere connects to in order to gather the information it needs. It refers specifically to the remote system in the inventory.
- Inventory
The inventory is the collection of Hosts that exosphere knows about. It is defined through the configuration file, in the Hosts section. Commands and functions that operate on the inventory will generally target All Hosts.
- Provider
A Provider is a platform-specific implementation of a package manager interface that Exosphere uses to gather information. For instance, on Debian and Ubuntu systems, the apt provider is used.
Providers are generally not exposed directly through configuration, just automatically detected based on the platform.
- Update
An Update, within exosphere, is an object representing a package that has a new version available for installation.
- Security
Whenever the term “Security” is used, it refers to the security status of an Update. Security Updates are updates that address security vulnerabilities in the software installed on the Host. Exosphere will generally report these with some form of emphasis, as they are more urgent than regular updates.
- Discovery
Discovery is the initial process through which Exosphere connects to a host and tries to determine platform details. This usually consists of:
Operating System: The Operating System installed on the host (Linux, FreeBSD, etc)
Version: The version of the operating system (20.04, 22.04, 8, etc)
Flavor: The distribution or flavor (Debian, Ubuntu, RedHat, etc)
Package Manager: The package manager in use (apt, dnf, yum, etc)
This usually only needs to be done once per host, but can be repeated if any details change, such as a new OS version or package manager change.
- Refresh
A Refresh is the process of querying the host for its current available updates. This is generally done by querying the package manager. The process is universally read-only, and does not perform any system changes, aside from affecting some metadata timestamps and caches on certain platforms and operating systems.
This is usually separate from a Repository Sync, but often can be combined into a single operation depending on context.
- Repositories
The Repositories are the generic term for the authoritative list of packages on the host platform. This generally consists of repositories. For instance, on Debian and Ubuntu systems, the repositories refer to the remote systems configured in /etc/apt/sources.list and friends. On RedHat-likes, it refers to the repositories configured in /etc/yum.repos.d/ and so on.
- Repository Sync
Synchronizing the repositories is the process of updating the local host cache from these remote servers, so that the next update check will have the latest information.
This is equivalent to running apt-get update on Debian-based systems, or dnf makecache on RedHat-based systems.
This process is generally safe and read-only, but on systems where sudo is required, it may update repository metadata system wide. This is generally not an issue, but if it is problematic, rest assured that the behavior is entirely opt-in, in these cases.