Hi,
With the AutoClear = False in the alarm template, it's possible not to clear the alarms automatically. In this case, alarms will move to clearable and not closed state (Clearing alarms | DataMiner Docs).
However, if the system is in Alarm Storm mode, it can happen that the alarms are closed even with the AutoClear = False. By default, when there are more than 1000 clearable alarm trees on a DMA, the newly generated clearable alarms will be closed instead of being clearable. Once the number of clearable alarm trees has dropped to less than 100, this protection mode is lifted, and newly generated alarms will be clearable again.
I saw that it's possible to use the ClearableAlarmStormProtection setting in the DataMiner.xml file and change the default max/min values: ClearableAlarmStormProtection element | DataMiner Docs
Is there any advice/rule to help define the ClearableAlarmStormProtection max and min values?
Hi Joaquim,
Simple answer: it depends on the capabilities of the system and database versus the number of trees a user wants to maintain and the specific implementation.
More in-depth:
Ideally, you want to close an alarm tree as soon as possible for several reasons.
Firstly, having thousands of "clearable" alarms is difficult to manage without automation. The question than arises if these alarms were needed in the first place, if they are not observed by a human operator who can take action because of them.
Secondly, clearable alarms are a contributing factor to excessively large alarm trees. Large alarm trees themselves can result in certain performance issues if left unchecked, e.g. when closing alarms also in the database or when managing the database in general.
Thirdly, clearable alarms also contribute to the overall alarm load (number of alarm trees instead of size), which may also have a noticeable impact on DataMiner, given how alarms are interwoven in the fabric of DataMiner.
As such, our recommendation is:
- Typically, avoid increasing as in normal circumstances, there are other alternatives to achieve what the user needs
- If you do increase, be aware that you yourself also have a mechanism setup to close said clearable alarms to avoid this measure from triggering
- If you do increase, review the alarms from time to time and ensure that all which needs to be closed is closed
- If you do increase, attempt to avoid closing too many alarms in one go