Understanding the system health score

The System Health dashboard provides a single place from which you can quickly determine the health of the system.

The system health health score can help you spot where your most severe health issues are, based on five core factors: Configuration, Capacity, System Utilization, Service Level Compliance and Storage Group (SG) Response Time. The area with the highest risk to your system health lowers the score until remedial actions are taken

The System Health panel displays values for the following high-level health or performance metrics: Configuration, Capacity, System Utilization, Storage Group (SG) response time, and Service Level compliance. It also displays an overall health score that is based on the lowest health score out of the five metrics. The health score is calculated every five minutes. The overall value is always calculated from all metric values. If a health score category is seen as stale or unknown, the overall health score is not updated. The previously calculated overall health score is displayed but its value is denoted as stale by setting the menu item to gray.

The System Utilization, Capacity, Storage Group (SG) response time, and Service Level compliance are based on performance information.

The Capacity health score is based on % Effective Used Capacity. Capacity levels are checked at the SRP level and SRP Emulation level (where a mixed SRP emulation is involved).

The capacity health scores are calculated as follows:

The System Utilization health score is calculated using the threshold limits of the following categories and metrics:

For each instance and metric for particular category, the threshold info is found. If not set, use the default thresholds. The default thresholds are:

FE Port: % busy - Critical 70

FE Director: % busy - Critical 70 ; Queue Depth Utilization - Critical 75

BE Port: % busy - Critical 70

BE Director (DA): % busy - Critical 70

SRDF Port: % busy - Critical 70

SRDF Director: % busy - Critical 70

DX Port: - % busy - Critical 70

External Director: % busy- Critical 70

EDS Director: % busy - Critical 70

Cache Partition: %WP utilization - Critical 75

EM Director: % busy - Critical 70

The system utilization score is calculated as follows:

The Storage Group Response health score is based on software category health scores. Certain key metrics are examined against threshold values and if they exceed a certain threshold, the health score is negatively affected.

For each instance and metric for particular category, the threshold info is found. If not found, default thresholds are used.

The Response Time, Read Response Time, Write Response Time metrics are ignored from the health score calculation if the alert is not enabled for the SG/metric.

The Service Level Compliance health score is based on Workload Planner (WLP) workload state. A reduction from the health score is performed when storage groups that have a service level that is defined are not meeting the service level requirements.

If the Service Level Compliance alert is disabled for the SG, it will be ignored from the health score calculation.

The Service Level compliance score is calculated as follows:

The Configuration health score is calculated every five minutes and is based on the director and port alerts in the system at the time of calculation. Unisphere does not support alert correlation or auto clearing, you are required to manually delete alerts that have been dealt with or are no longer relevant as these impact on the hardware health score until they are removed from Unisphere.

The Configuration health score is calculated as follows:

For embedded Unisphere systems that are running PowerMaxOS 10 (6079) and that support PowerMax File, auto clearing of PowerMax File alerts is supported.

Auto clearing of alerts is a mechanism whereby if an alert of severity Normal arrives into the system, this alert clears the alerts relating to this normal alert that are already there and have a higher severity.