|
Measures reported by EMCPvMeCtlStTest
The storage controller is essentially a server that's responsible for performing a wide range of functions for the storage system. Each controller has an I/O path to communicate to the storage network or the directly-attached servers, an I/O path that communicates to the attached storage devices or shelves of devices, and a processor that handles the movement of data as well as other data-related functions, such as RAID and volume management. In the modern data center, the performance of the storage system can be directly impacted (and in many cases determined) by the overall health of the storage controller. In single-controller configurations, if the storage controller crashes, then the storage system as a whole will become inaccessible to users. This is why, it is good practice to go for dual-controller configurations. A dual-controller configuration improves application availability because in the unlikely event of a controller failure, the affected controller fails over to the surviving controller with little interruption to the flow of data. However, since fail over occurs automatically upon the failure of a controller, administrators may not even know why the primary controller failed or whether the secondary has taken over or not! This is when the EMCPvMeCtlStTest comes in handy!
This test not only monitors the status of each controller in the EMC PowerVault ME storage system, but also promptly reports controller failures and the reason for the failure. In the process, the test also indicates whether the primary controller has failed over to the secondary or not.
Outputs of the test : One set of results for each controller of the EMC PowerVault ME storage system being monitored.
The measures made by this test are as follows:
| Measurement |
Description |
Measurement Unit |
Interpretation |
| status |
Indicates the current operational status of this controller. |
|
The values reported by this measure and its numeric equivalents are mentioned in the table below:
| Measure Value |
Numeric Value |
| Down |
0 |
| Unknown |
1 |
| Operational |
2 |
| Not installed |
3 |
Note:
By default, this measure reports the above-mentioned Measure Values while indicating the operational status of a controller. However, in the graph of this measure, controller status will be represented using the corresponding numeric equivalents only. |
| failedOver |
Indicates whether this controller has failed over to the partner controller i.e., the secondary controller (in a redundant setup). |
|
The values reported by this measure and its numeric equivalents are mentioned in the table below:
| Measure Value |
Numeric Value |
| Yes |
0 |
| No |
1 |
Note:
By default, this measure reports the above-mentioned Measure Values while indicating the failed over status of this controller. However, the graph of this measure will be represented using the corresponding numeric equivalents of the Measure Values as mentioned in the table above.
The detailed diagnosis capability of this measure if enabled, lists the time, the name of the controller and the reason for the fail over of the controller. |
| health |
Indicates the overall health of this controller. |
|
The values reported by this measure and its numeric equivalents are mentioned in the table below:
| Measure Value |
Numeric Value |
| Fault |
0 |
| OK |
1 |
| Unknown |
2 |
Note:
By default, this measure reports the above-mentioned States while indicating the overall health of this controller. However, in the graph of this measure, controller health will be represented using the corresponding numeric equivalents only.
The detailed diagnosis capability of this measure if enabled, lists the time, the name of the controller and the reason for the overall health of the controller. |
|