In last week’s post, we learned how to create a custom dashboard to view vSAN disk group metrics for a selected cluster. That dashboard works awesome if you want to look at a particular disk group. But what if you want to compare that cluster’s disk groups for specific metrics in a single representation and avoiding all that back and forth comparison? Impossible you say?
Today, we’re going to take things a step further and include some views into a dashboard so that we can compare all disk groups for a selected cluster to quickly identify anomalies.
Creating the view
To begin, we’ll start by creating a new view. Select dashboards from the top menu, views from the left-hand menu, and click on the green plus sign to create a view.
Give this view a name and a description of it’s intended use.
Select a trendline graph from the presentation menu. Depending on the number of disk groups you have for each of your host clusters, you may want to adjust the maximum number of plot lines. 25 is more than enough for my lab.
In the subjects menu, expand the vSAN Adapter and select vSAN Disk Group.
Select the metric you want to view from the data menu. Note that you can plot multiple metrics on the same chart, but for the sake of keeping things readable, we’ll just select one. In this example I expanded the disk I/O group and selected the average write latency (ms).
For the metric configuration, we’ll uncheck the trend of the historic data and set the forecast to only show the next day. You could even uncheck forecasting all together as this dashboard will mostly be used to troubleshoot events that occurred in the past. However, I like to see where things are headed so I’ll keep this checked.
Under the time settings tab, we’ll leave it to the last seven days, but you can adjust as needed.
In case you’re wondering, I don’t think there’s a distinguishable difference between the relative date range and absolute date range. Unfortunately, the documentation appears to have an incorrect description for the absolute date range. I believe the documentation is describing the advanced time range settings where you can report on all data from the first day of the quarter, 2nd day of the week, month, whatever.
And lastly, the filter is a pretty cool feature that can help clean up our data a bit.
We won’t use filters for this particular view, but you could say just show me the disk groups where the average write latency exceeded 10ms.
Click Save.
Repeat this process for any other metrics that you want to compare. One of the great benefits to using views is that you have the ability to add these same views to a report!
Create the dashboard
Let’s not reinvent our dashboard that we created last week. Instead, we’ll clone that dashboard first by selecting actions -> manage dashboards,
then select our vSAN Disk Group Performance dashboard, and click the clone dashboard button.
Give the new dashboard a name. I creatively came up with vSAN Disk Group Compare Metrics.
Select the newly minted dashboard and click on the pencil icon to edit it.
I updated the description for this dashboard to reflect its intended use.
For our new dashboard, we only want to reuse the select cluster object list which will drive our views. Go ahead and delete the heat map, scoreboard, and object relationship widgets by clicking on the X located in the top right corner of each widget.
Next, drag a new view widget on to the dashboard for each of our views.
Click on the view widget’s pencil icon to edit the widget.
Give the widget a title and select one of your newly created views. To speed things up, use the filters field to display all vSAN views.
Repeat this step for the other views you added to the dashboard.
The final step is to configure the widget interactions. This dashboard simply displays the disk group metrics for the selected host cluster. That means we’ll pick the select cluster object list for each of our four views and click apply interactions.
Click save and you’re done!
Enjoy your new dashboard. May it help you quickly identify and remediate issues!
