Hello SharePointers,

When you do migration from SharePoint 2010 to 2013, you need to keep your old site collection as read only for the business users and do the migration simultaneously. You can set Read only at site collection level.There are two ways to achieve the read only mode.  The one option is to use PowerShell Mode or through Central Administrator.

PowerShell

Set-SPSite -Identity “” -LockState “”

Example

Set-SPSite -Identity “https://mydev/dev” -LockState “READONLY”

Central Administration

• Open Central Administration, click Application Management.
• On the Application Management , under Site Collections section, click Configure quotas and locks.
• If the site collection you want isn’t already selected, under Site Collection section, on the Site Collection menu, click Change Site Collection.
• Use the Select Site Collection page to select a site collection.
• On the Site Collection Quotas and Locks page, in the Site Lock Information section, select Readonly as the option.
• Click ok and close the page.

Happy SharePointing Folks 🙂