Spotlight on Oracle 10.4 - Release Notes

Connect to an Exadata Storage Server (Cells)

Refer to this page for background information on Spotlight's connection to Exadata Storage Server (cells).

Note: Spotlight monitoring of Oracle RAC systems requires additional licensing.

How Spotlight connects to Exadata Storage Cells

Spotlight does not directly connect to the Exadata Storage Cells. It uses one of the database nodes as an intermediary to tunnel through to the cell storage nodes to retrieve performance metrics. In a default Oracle Exadata installation, the client will not have direct access to the Storage cells as these are private to the appliance. The database nodes are generally public and can be accessed by the Spotlight client.

1. Spotlight makes an Oracle connection to the Exadata database nodes.

   When this is successful, Spotlight runs a SQL query against an Oracle view - v$active_instances - to obtain the operating system host name. On further processing Spotlight also obtains the domain information. This information is used to establish an operating system connection to one of the database nodes.

2. Spotlight establishes an operating system connection to one of the Exadata database nodes.

3. Spotlight uses the Oracle connection to one of the database nodes to execute another SQL query that retrieves Cell IPs from v$cell and other Cell information (such as the host name and domain) from v$cell_config.

4. 4. Given the information obtained in the preceding steps, Spotlight uses port forwarding to tunnel through to the Exadata Storage Cells via one of the database nodes.

   • Spotlight uses the host names obtained from v$cell_config. It binds these host names to the open SSH ports obtained from the same view.
   • Free local ports on the Spotlight client are assigned to receive data for each tunneled connection (for each connection to each online storage node).

   The host names resolve to IP addresses on the management network. You can override this via the Verify Storage Node Connection Details Dialogdialog that opens on the first connection to the Exadata system.

   It is recommended that the celladmin operating system user account be used for connecting to the Storage Cells.