hostaccessible

Hostaccessible is a term used in information technology to describe an entity that can be accessed from the host system. A host-accessible resource is reachable by the host’s processes, either through network connections to services bound to the host or through direct access to mounted filesystems or devices. The concept is commonly discussed in relation to containers, virtual machines, and sandboxed environments, where isolation can limit visibility of internal resources to the guest environment unless explicit configuration exposes them to the host.

In container contexts, a service running inside a container is host-accessible if it binds to a host-facing network interface or if the container is configured with port mappings or host network mode that allow the host to reach the service. For filesystems, mounting a host directory into a container creates a host-accessible path. In virtualization, sharing folders or devices between host and guest also creates host-accessible resources.

Configuring host accessibility often involves security trade-offs. Exposing ports or mounts increases the attack surface and the risk of data leakage, so access should be restricted to what is necessary and protected by authentication, encryption, and appropriate access controls.

The term does not imply universal semantics across platforms, and implementations vary by system and toolset. Related concepts include sandboxing, containerization, virtualization, port binding, and volume mounting.