An alias is a globally unique, DNS-like string that is associated with a destination resource. You can establish a session to a target by referencing its alias, instead of having to provide a target ID or target name and scope ID.
For example, if you have an alias `boundary.dev`, you can use it to connect to a target with the following command: `boundary connect ssh boundary.dev`.
When you create a resource in Boundary, it assigns the resource a randomly generated identifier. You must use those IDs to perform actions in Boundary. When you connect to a target using the terminal, you must reference the target ID or target name and scope name.
Aliases simplify this process. When you create an alias and associate it with a target, you can later use the alias `value` instead of the target ID in commands. Boundary automatically resolves to the target that the alias references.
The existence of an alias for a Boundary resource does not change how permissions function. Anyone can attempt to use an alias to access a target, but if you do not have permission to access the target, the attempt fails. You can create an alias for a target, even if you do not have permission to access the target.
Separating the permissions from aliases and destination resources means a different set of people can manage the aliases than the people who have permission to operate on targets. For example, you may have a project with a sensitive set of targets. You can configure Boundary to allow a select few users to manage those targets, while a different group of users manage the aliases.
An alias is a globally unique, DNS-like string that is associated with a destination resource. The alias `value` parameter does not have to be delimited by a suffix, and can be just a hostname.
Examples of valid aliases include `database.boundary` and `webserver.boundary`.
### Single word aliases and transparent sessions
HashiCorp recommends that you do not use single-word aliases such as `webserver` as opposed to `webserver.boundary`, because single-word aliases do not work intuitively on Windows.
Windows DNS resolution does not support resolving unqualified single word DNS hostnames. You can make the hostname fully qualified, but is not intuitive to most users.
You can only create aliases in the `global` scope. However, you can associate aliases with targets or hosts from any scope. Support for additional resource types may be added in the future.
If you delete a project, Boundary clears the `destination_id` parameter for any aliases that resolve to targets in that project, so that they no longer function.
