Hello Everyone, I am writing this article to help everyone in choosing the right threshold for the volume Disks utilization in your environment. When you are dealing with bulk of database storage files (mount points), Applications then its not easy to decide the threshold level for all the storage disks since the count of Volumes reaches upto 50k and the size of Volumes varies from MB's to TB's. So in these situations you need to have an intelligent way of defining thresholds on the volumes also you have to select which volume drive you want to alert or which not. I am sharing an idea that I Implemented with the help of my Supervisor in my previous company. Hope this will help you in setting up the volume alert in a right manner.
1. Create a Custom Property on Volumes that will act as a Flag for turning on/off utilization alerts on the volumes. E.g. We created Ignore Disk, and if it is set to Yes then alert will not go out and by-default value remain as False which means any new volume will be enabled for alert always without doing anything in it. Since ignoring alerts for volumes are very rare.
2. Pull out the List of all the Volume Drives from your environment with their total size, this will help in defining the appropriate thresholds. For example we got volume disk drives in size ranging from 100 KB to 5 TB.
3. Now Draw the Metrics for the range of volume size and what should be the Threshold for that particular range. Below is what we drew for our environment.
Volume Size Threshold
1 KB to 1 MB 80%
1 MB to 50 MB 85%
50 MB to 200 MB 88%
200 MB to 1 GB 90%
1 GB to 20 GB 92%
20 GB to 100 GB 94%
100 GB to 500 GB 95%
More than 500 GB Less than 50 GB
4. Now create an alert with the trigger conditions based on above threshold , put above conditions in OR condition. Sharing snapshot below for reference. Since the Variable for Volume Size give values in bytes so you need to
convert KB, MB and GB in Bytes first then put in the alerts.
5. Select applicable Action type - Like email, event etc.
6. Create another Custom Property for Customized Threshold. For example there are certain drives which are exceptional and could not fit in above threshold values then you can define their threshold exclusively in that custom property and call the same again in the alert trigger condition instead of above regular metrics.
Note - You can change the Volume Size Range and its Threshold in Percentage based on the Volume data in your environment and also you can put more conditions to exclude Volume Types like Physical, Virtual memory etc.