SharePoint 2010 was supporting the In-place upgrade, the only advantage I see from this is reducing the required number of environments ya but you still have to take backup right?

SharePoint installation is smooth yes but upgrade is not unless your environment is empty! So who would do In-place upgrade for SharePoint!! And what if it failed as always I believe, you will have to start new environment from scratch … that will be sweet times J .. I am just laughing at that.

In-place upgrade already have problems mainly and importantly is performance issues.

Microsoft realized this, oh thank god! And decided to remove it from SharePoint 2013.

In case you are reading this and don’t know what is In-place upgrade means; read below:

“An upgrade to SharePoint Server 2010 or SharePoint Foundation 2010 provides an option to install the new version over the earlier version on the same hardware. This is called an in-place upgrade. During this process, the complete installation, that includes databases and sites, is upgraded in a fixed order. Although this is a simple method, in-place upgrade presents problems in performance and control for a farm administrator. There was no way to control the order in which content is upgraded, and a failure in a particular site collection could stop the whole process.”

SharePoint 2013 does not support In-place upgrade

So the supported and recommended upgrade is the database-attach upgrade.

The database-attach upgrade method offers more flexibility, more control, and a better success rate.

To use a database attach upgrade, you will need to complete the following tasks:

  1. Create and configure a new farm that is separate from the old farm
  2. Copy the content and services databases to the new farm
  3. Upgrade the data and sites

You can upgrade the content databases in any order and upgrade several databases at the same time to speed up the overall process.

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