Is there any upgrade tool or documentation available for migration of sitecore 7 to sitecore 9. The current upgrade documentation for sitecore 9 require v8 as prerequisite. Can the same be used for v7 as well?
You can use Sitecore Migration tool 3.1
The Sitecore Express Migration Tool makes it easy for customers to help migrate Sitecore 6.6,7.2, 7.5 or 8.0 to the latest version of Sitecore Experience Platform 9.0 without the need to gradually upgrade from version to version. Please note that DMS data to xDB will still require the use of the conversion tools found on the Sitecore Experience Platform download pages.
The Express Migration Tool Migrates:
- Content items and media
- All users, roles and security permissions
- Assists with configuration migrations Web Forms For Marketers items and data
You can download from this link : https://dev.sitecore.net/Downloads/Express_Migration_Tool/31/Express_Migration_Tool_31.aspx