In the context of an Oracle Enterprise Manager

Oracle Enterprise Manager

The computer application Oracle Enterprise Manager aims to manage software produced by Oracle Corporation as well as by some non-Oracle entities.-Oracle Enterprise Manager Database Control :...

 (OEM) environment, an Oracle Management Server (OMS) functions as a middle tier between "Oracle intelligent agents" (which may operate on multiple nodes and by default use a schema named DBSNMP) and management consoles, where DBA

Database administrator

A database administrator is a person responsible for the design, implementation, maintenance and repair of an organization's database. They are also known by the titles Database Coordinator or Database Programmer, and is closely related to the Database Analyst, Database Modeller, Programmer...

s view and control their OEM domain(s).

An OMS has special links with a repository database, used for storing OEM details.