From what I understand I think it's not going to be a straight migration - you're going to have to rewrite a lot of your code, too.

How much will depend a lot on how you have created your site - if you use ModelBuilder then maybe your views won't change much, but if you use stuff like Model.Content.GetPropertyValue("") then that will need rewriting. Same goes for if you have your own controllers, as Umbraco 8 will use DI rather than singletons like UmbracoContext etc. They may leave legacy stubs for these to help migrate, but ultimately the architecture is fundamentally changing in a lot of places.

Likewise, a lot of 3rd party packages are unlikely to work until they get updated, too.

So I don't expect it to be a straightforward task. Last I heard Neils was saying there wasn't any immediate automatic upgrade path, but things might have changed. Only core team can answer this definitely as it's a work in progress.

This post was the first for me in search results so I'll paste the latest info I've seen below for anyone else that might need it:

While automatic upgrades from Umbraco 7 to Umbraco 8 will not be possible, very soon it will be possible to migrate your content (content/media/members) from the latest version of Umbraco 7 to Umbraco 8.0. We will let you know when we have more information ready on this, including documentation and information on best practices to follow. In the meantime, you can read more on the topic in our developers perspective blog post.

I tried the upgrade of a fresh Umbraco 7.13.2 install. The DB upgrade fails with the following message:

{
    "@t": "2019-03-12T09:46:31.3864270Z",
    "@mt": "Installation step {Step} failed.",
    "@l": "Error",
    "@x": "System.Reflection.TargetInvocationException: Ein Aufrufziel hat einen Ausnahmefehler verursacht. ---> 
Umbraco.Web.Install.InstallException: The database failed to upgrade.
ERROR: The database configuration failed with the following message:
Unknown state \"{init-7.13.2}\".\n
    Please check log file for additional information (can be found in '/App_Data/Logs/UmbracoTraceLog.txt')\r\n
       bei Umbraco.Web.Install.InstallSteps.DatabaseUpgradeStep.ExecuteAsync(Object model)\r\n   --- Ende der internen Ausnahmestapelüberwachung ---\r\n
       bei System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)\r\n
       bei System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)\r\n
       bei System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)\r\n   bei Umbraco.Web.Install.Controllers.InstallApiController.<ExecuteStepAsync>d__14.MoveNext()",
            "Step": "DatabaseUpgrade",
            "SourceContext": "Umbraco.Web.Install.Controllers.InstallApiController",
            "ProcessId": 19212,
            "ProcessName": "iisexpress",
            "ThreadId": 35,
            "AppDomainId": 6,
            "AppDomainAppId": "LMW3SVC2ROOT",
            "MachineName": "DESKTOP-7DCFOJ9",
            "Log4NetLevel": "ERROR",
            "HttpRequestNumber": 2,
            "HttpRequestId": "3ee0cddc-57ba-4aa6-867c-5b3cf4b59ead"
        }

Does anybody have any insights regarding the upgrade?

I forgot to mention, that I read exactly the article by Claus Jension. Quote:

For that reason, our suggested migration path will be that you temporarily disable all of your existing Umbraco 7 code and then simply start out by upgrading your database schema with a blank Umbraco 8 site.

That's exactly what I have done. I made a blank Umbraco 8 site and replaced the database with the database from a fresh Umbraco 7 Installation (I changed the Umbraco.Core.ConfigurationStatus in web.config to 7.13.2).

The log file shows that the database conversion starts, but it fails, because it doesn't know the Umbraco 7.13.2 version. Maybe it works with older versions.

The question is: Is there already any support for migration? If this is the case, how does it work? If it is not the case, when can we expect to get such support?

This is also being discussed here, can someone from the core team confirm what the situation is as the Claus Jension article seems to contradict what a lot of people believe about v7 to v8.

From what I understand, the migration tool will be available in the 8.1 version.

-Jason

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