Visit Esri Support for general support information on Esri's Supported Environment Policy as well as information on earlier versions.
Minimum supported database versions
PostgreSQL 9.3.5 (64 bit)
PostgreSQL 9.2.9 (64 bit)
PostgreSQL 9.1.14 (64 bit)
Supported operating systems
The operating system of the server your database management system is installed on must meet ArcGIS for Server operating system requirements
Software required to connect to a DBMS
Your client machine (for example, the one running ArcMap) will need to have the appropriate client files installed for the RDBMS you are using. These client files are available from their respective RDBMS vendors, but some are also available on My Esri as a convenience. See Database clients for more information. RDBMS client files available from My Esri are IBM DB2, IBM Informix, Microsoft SQL Server, and PostgreSQL. Client files for ALTIBASE, IBM Netezza, Oracle, SAP HANA, and Teradata are not available on My Esri and must be obtained from the RDBMS vendors.
Esri tests and certifies specific major and minor releases of the PostgreSQL installations that are available from PostgreSQL.org. For each PostgreSQL release Esri supports, available PostGIS modules are also tested and certified. No other modules extending PostgreSQL functionality are included in Esri certification.