Exadata Cell Disk Space Test

Within the storage servers, a logical unit number (LUN) defines a logical storage resource from which a single cell disk can be created. A cell disk is an Oracle Exadata System Software abstraction built on the top of a LUN. Soon after a cell disk is created from the LUN, it is managed by Oracle Exadata System Software and is further divided into grid disks, which are directly exposed to the database and Oracle Automatic Storage Management (Oracle ASM) instances. Each grid disk is a potentially non-contiguous partition of the cell disk that is directly exposed to Oracle ASM to be used for the Oracle ASM disk group creations and expansions. This level of virtualization enables multiple Oracle ASM clusters and multiple databases to share the same physical disk. Such sharing also provides optimal use of disk capacity and bandwidth.

If a cell disk is in critical state or is running out of space, then the data stored in the cell disk may become unavailable to the users. To avoid such interruption in the availability of data, it is essential to monitor the cell disks at periodic intervals. The Exadata Cell Disk Space test helps administrators in this regard!

This test auto-discovers the cell disks available in the target Oracle Exadata Storage Server and for each cell disk reports the status and the space utilization. Using this test, administrators can figure out those cell disks to which additional storage space needs to be allocated. Administrators can also isolate the cell disks that are in critical state and initiate remedial measures.

Target of the test : Oracle Exadata Storage Server

Agent deploying the test : A remote agent

Outputs of the test : One set of results for each cell disk on the target Oracle Exadata Storage Server that is being monitored

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed


The IP address of the host for which this test is to be configured.


The port number at which the specified host listens. By default, this is NULL.

Username, Password and Confirm Password

By default, this test uses the Cell Control Command-Line Interface (CellCLI) to pull out the required metrics. To use the CLI, the test first needs to connect to the target storage server via SSH, and then run commands using CLI. For running the commands, this test requires the credentials of a cellmonitor user. Specify the login credentials of such a user in the Username and Password text boxes and confirm the Password by retyping it in the Confirm Password text box.

SSH Port

This test uses the Cell CLI to pull metrics from the target Oracle Exadata Storage Server. To run the CLI commands, this test first needs to establish an SSH connection with the target storage server. To enable the test to establish this connection, specify the SSH Port here.


 Specify the time duration for which this test should wait for a response from the storage system in the Timeout text box. By default, this is 120 seconds.

Detailed Diagnosis

To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

  • The eG manager license should allow the detailed diagnosis capability
  • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Cell disk status

Indicates the current status of this cell disk.


The table below indicates the values that this measure can report and their corresponding numeric equivalents:

Measure value Numeric Value
Normal 100
Import required 90
Critical 50


By default, this measure reports the above-mentioned Measure Values while indicating the current status of the cell disk. However, in the graph of this measure, the status of the cell disk will be represented using the corresponding numeric equivalents only.

The detailed diagnosis of this measure lists the date and time on which the cell disk was created, the physical disk associated with the cell disk and the comments.

Total space

Indicates the total amount of space allocated to this cell disk.



Free space

Indicates the amount of space available for use in this cell disk.


A high value is desired for this measure.

Space utilization

Indicates the percentage of space that is utilized by this cell disk.


A value close to 100 indicates that the cell disk is running out of space. Administrators may be required to add additional space to the cell disk.

Compare the value of this measure across cell disks to figure out the cell disk that has utilized maximum amount of space.

Error count

Indicates the total number of errors encountered on this cell disk.


Ideally, the value of this measure should be zero.