In this document, the different upgrade scenarios, and the support for each of them will be outlined.
Please read: How do I upgrade the software?
The following scenarios go into specifics.
As a general rule, major versions may only be upgraded, never downgraded, while minor versions within the same major may be up/downgraded at will.
sw1.x - sw2.x
The version number is split into 4 parts; [Major].[Minor].[Type].r[Revision][-<optional-description>] like 2.6.1.r145
The version number is split into 3 parts; [Major].[Minor].[Revision][-<optional-description>] like 3.0.22
Scenario 1: Software update to sw3.x.x - IMPORTANT
A system with a controller at sw2.9.1.r179 is supported to directly update to sw3.x.
Systems on sw2.8.1.r171 or lower need to be updated to sw2.9.1.r179.
Scenario 2: an old controller with a new endpoint - not supported
A system with a controller at [Major] < endpoint [Major] is not supported. This has the consequence that in order to add additional endpoints to an existing installation, which is running at a noncurrent software version, the software version must be bumped to at least the same major version as the endpoint.
Scenario 3: a new controller with an old endpoint - supported
A system with a controller at [Major] >= endpoint [Major] is supported. This means that you can freely use any older endpoints with an updated controller.
Scenario 4: new controller downgrade major - not supported
A controller may never be downgraded to a previous major version.
Scenario 5: new controller downgrade minor - supported (but not encouraged)
Downgrades within between minor versions are supported, as long as they are in the same major version. It is not encouraged to do so, as the test coverage for downgrades between any two versions will inherently be below.
In general, are all released software versions backwards compatible in regards to the controller and endpoint hardware revisions and models.
At the time of writing, it is not known if there will be versions that are not backwards compatible.
This means ie. that the 64/4 Controller Rev. A and 32/2 Controller Rev. A can be updated with the latest released software. Software-based features will be enabled on Rev. A controllers, hardware-based features, like port bundling/combining will of cause not be possible.
Licenses can be installed and deleted on the controllers from sw2.7.x. A deleted license can be re-installed. The order of installation of licenses is subordinate.
When upgrading an EoC system with installed licenses, the licenses will not be altered/deleted.
This means downgrading below this version will result in licenses not being displayed. The licenses will still be active and the system will be running, provided the configuration is not utilizing features introduced in a later version than the one the controller is downgraded to.