aa363691_leged_Installation___Nik_Patel__2
[0] SharePoint Installation/Setup Account(e.g. sp_install) [1] This account is used to perform these tasks – Setup and SharePoint Products Configuration Wizard Log in to the Server using this account for installing SharePoint binaries and running SharePoint configuration wizard. Performs post-installation updates, patches, and installation of products such as language packs. Will provision the SharePoint Farm Account during the SharePoint product config wizard. [3] Member of Local Administrators Group on each server where SharePoint Installer would run (aka. WFE and Application Servers, excluding SQL Server or SMTP Server). [4] SQL Server Login on the database server. Needs access to the SQL Server where SharePoint 2010 databases will run. Member of following SQL Server Security Roles – SecurityAdmin fixed server role and dbcreator fixed server role. SharePoint setup and psconfig.exe requires these privileges to create databases and to create SQL logins for SharePoint accounts. Not required during installation but may be required for patching (needs to confirm!!) – Member of the db_owner fixed database role, if you are running powershell cmdlets that would affect the database. In reality, installation account requires the SharePoint_Shell_Access database role for any database that you want to create or modify using Windows PowerShell. This role is currently equivalent to dbowner, but is a separate role. [5] AD Group Membership Changes – After you run the configuration wizards, machine-level permissions for this account are added: Membership in the WSS_ADMIN_WPG Windows security group. SQL Database Changes – After you run the configuration wizards, database permissions are added: DB_OWNER on the SharePoint Server 2010 server farm configuration database. DB_OWNER on the SharePoint Server 2010 Central Administration content database. Never have access to the Service Application Databases or Web Application Content Databases Windows Services Changes Configures the SharePoint 2010 Timer Service (SPTimerV4) to run under farm (sp_farm) account Configures the SharePoint Admin Windows Service (SPAdminV4) to run under Local System user Configures the SharePoint VSS Writer (SPWriterV4) to run under Local System user Configures the SharePoint Tracing Service (SPTraceV4) under Local Service user [2] 
Must be Domain User Account. Local User Accounts are not supported.
SharePoint 2010 Service Account References for Least-Privileged Installation | Nik Patel
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