versions - List versions supported by the server, request a specific version





Warning:The versions command is deprecated. Please use the REST-API for long term supported scripting.

versions displays a list of service / version strings that are supported by the server. A specific version can be requested for a command or a shell by using the v=VERSION:USER_AGENT prefix when running a command or starting the interactive shell. If the server does not support the requested version, the command will fail and an error message will be displayed.

A shell’s version may only be specified when it is created and may not be modified afterward. If a version is not specified for a command or shell, it is assumed to be the latest version.

Version Strings

The version strings returned by versions and used by the v= prefix should be considered opaque tokens and only tested for equality. Valid version characters are any printable character excluding whitespace.

Example version strings include:

  • transfer/1.0.1-3abc

  • transfer/2.0beta

If the service portion is omitted when requesting a version, it is assumed to be "transfer".

User Agent

A user agent must be supplied when requesting a version via the v= prefix. This user agent string must be at least 6 characters long and may not contain whitespace or the ":" character. The user agent string SHOULD identify the client / consumer software being used and its version, for example "MyProgram/3.1".


The client program "MyProgram/3.1" requests version 1.1 of the transfer service for a command:

$ ssh v=transfer/1.1:MyProgram/3.1 status -a

Request version 1.1 (transfer service assumed) for a shell:

$ ssh -t v=1.1:MyProgram/3.1

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