# Multiple-host NMS OAM

If your resources are distributed over several systems (multiple CPUs, chassis, or both) that are linked over an IP network, you can set up a multiple-host configuration of NMS OAM. This configuration enables an application running on one system to access and manage resources on other systems.

A multiple-host NMS OAM configuration consists of several hosts (CPUs). One of these hosts, the management host, configures and manages the resources (such as boards) on other hosts that are called resource hosts. The following illustration shows the relationship between the management host and resource hosts:

Each resource host runs an instance of the Natural Access Server (ctdaemon), including NMS OAM. Each resource host also has its own NMS OAM database containing data for the components on that host only.

Management applications and utilities, such as the NMS OAM utilities, reside on the management host. The configuration text files also reside on the management host. The following illustration shows NMS OAM host components:

If a management host includes resources that require management, the management host can also serve as a resource host. In this case, the management host also must run an instance of the Natural Access Server (ctdaemon), including NMS OAM. The database on this host contains information about the local resources only, even if the management host is also managing other resource hosts.

The utilities on the management host are used to configure the database on each resource host, one database at a time. The following illustration shows configuring the NMS OAM database on a resource host:

Applications on the management host can direct NMS OAM on a resource host to configure, start, and manage its resources based on the NMS OAM database.