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Cloud Monitor

Alert policies

Alert principles

This topic describes the detailed process of alert triggering, execution, and recovery after an alert policy is created.

Alerting process

Metric thresholds reached

For example, the alert trigger conditions in an alert policy are as follows:

Average disk read/write bandwidth exceeds 58 MiB/s for one cycle.

Maximum disk read/write bandwidth exceeds 58 MiB/s for one cycle.

Minimum disk read/write bandwidth exceeds 58 MiB/s for one cycle.

The alert process details are as follows:

Trigger condition

Metric

Alert detection time

Alert recovery

12:04

12:05

12:06

12:07

12:08

12:09

12:10

12:11

···

12:15

Maximum disk read/write bandwidth exceeds 58 MiB/s for one cycle

Maximum

Not higher than the threshold

Exceeds the threshold, triggering an alert

The metric remains above the threshold, keeping the alert from recovery

Average disk read/write bandwidth exceeds 58 MiB/s for one cycle

Average

Not higher than the threshold

Exceeds the threshold, triggering an alert

Below the threshold

No subsequent alert is triggered for five consecutive cycles, leading to alert recovery

A recovery notification is sent using the specified method at 12:15

Minimum disk read/write bandwidth exceeds 58 MiB/s for one cycle

Minimum

Not higher than the threshold

No alert triggered

Cycle-over-cycle comparison thresholds reached

For example, the alert trigger conditions in an alert policy are as follows:

Average disk read/write bandwidth has a 10% cycle-over-cycle rise or drop for three consecutive cycles.

The alert process details are as follows:

Trigger condition

Metric

Alert detection time

Alert recovery

12:04

12:05

12:06

12:07

12:08

...

12:12

Average disk read/write bandwidth has a 10% cycle-over-cycle rise or drop for three consecutive cycles.

Cycle-over-cycle average comparison

The metric meets the alert threshold for fewer than three consecutive cycles, failing to trigger an alert

The metric reaches the alert threshold for three consecutive cycles, triggering an alert.

Does not reach the alert threshold.

No subsequent alert is triggered for five consecutive cycles, leading to alert recovery.

Send recovery notifications using the specified method.

Edge cases

Cycle-over-cycle change = (nth cycle - (n-1)th cycle) / (n-1)th cycle

Data for cycle n-1	Data for cycle n	Descriptions
0	Not zero	The cycle-over-cycle change is infinite and exceeds any threshold setting. The trigger condition is met in this cycle.
No data reported	No data reported or any value reported	Unable to calculate the cycle-over-cycle change. The trigger condition is not met in this cycle.
No data reported or any value reported	No data reported	Unable to calculate the cycle-over-cycle change. The trigger condition is not met in this cycle.
n	0	The cycle-over-cycle change is -1 (-100%). The trigger condition is not met in this cycle.
0	0	No cycle-over-cycle change. The trigger condition is not met in this cycle.

Period-over-period change from yesterday = (Value for the current cycle - Value for the same cycle of yesterday) / Value for the same cycle of yesterday

Period-over-period change from the last week = (Value for the current cycle - Value for the same cycle last week) / Value for the same cycle last week

Data for the same cycle yesterday / the same cycle last week / the previous cycle	Data within the current cycle	Descriptions
0	Not zero	The period-over-period change is infinite and exceeds any threshold setting. The trigger condition is met in this cycle.
No data reported	No data reported or any value reported	Unable to calculate the period-over-period change. The trigger condition is not met in this cycle.
No data reported or any value reported	No data reported	Unable to calculate the period-over-period change. The trigger condition is not met in this cycle.
n	0	The period-over-period change is -1 (-100%). The trigger condition is not met in this cycle.
0	0	No change from the period-over-period comparison. The trigger condition is not met in this cycle.

Last updated: 2026.07.10 14:02:23