How do I set DeploymentPro (legacy) to download only a subset of data to the local OST file?
If you want to manipulate the amount of data that is downloaded to users' OST files, then this can be set via Group Policy.
To set this you can use the Group Policy templates, which are available from the Microsoft Web site (see https://technet.microsoft.com/en-us/library/Cc178992.aspx for more information). The Group Policy template files are Outlk15.admx and Outlk15.adml. If you use Group Policy to manage this setting, the following registry data is utilized by Outlook.
Key: HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\15.0\Outlook\Cached ModeDWORD: SyncWindowSettingValue: integer value (Decimal) specifying the number of months (use only the following values)
0 = All (entire mailbox)1 = one month of email items3 = three months of email items6 = six months of email items12 = twelve months of email items24 = twenty-four months of email items
If you are concerned with bandwidth when DeploymentPro (legacy) is being used to configure Outlook profiles at cutover (which in turn will also download the OST file to each users' local drive), then you could set this to either 1 or 3 months before your MX record cutover, and then increase this number in the subsequent weeks, post-migration, so that users will then have a larger portion of their mailbox downloaded and synched to the local OST file.