threshold/website/content/docs/concepts/domain-model/hosts.mdx

---
layout: docs
page_title: Host resource
description: >-
  Learn about using host resources to represent computing elements that are reachable from Boundary. You can organize hosts in host sets and host catalogs.
---

# Hosts

A host is a resource
that represents a computing element with a network address
reachable from Boundary.
A host belongs to a [host catalog][].
Hosts can only be associated with [host sets][]
from the same host catalog as the host.

## Plugin-based host information

Plugin-based hosts are read-only.  They are synced by an installed plugin on
the boundary system using the configuration provided it from the
[host catalog][] and [host set][] at an interval (configurable in the
[host set][]).

## Attributes

A host has the following configurable attributes:

- `name` - (optional)
  If set, the `name` must be unique within the host's parent [host catalog][].

- `description` - (optional)

### Static host attributes

Static host types have the following additional attribute:

- `address` - (required)
  Must be at least 3 characters long and not greater than 255 characters.

## Referenced by

- [Host Catalog][]
- [Host Set][]

[host catalog]: /boundary/docs/concepts/domain-model/host-catalogs
[host catalogs]: /boundary/docs/concepts/domain-model/host-catalogs
[host set]: /boundary/docs/concepts/domain-model/host-sets
[host sets]: /boundary/docs/concepts/domain-model/host-sets

## Service API docs

The following services are relevant to this resource:

- [Host Service](/boundary/api-docs/host-service)