In the recent past vSAN 6.7U3 has been released with rich feature set & there have been plenty of performance enhancements being done in this build. We already know about ESXTOP tool which every VMware administrator uses daily to look around ESXI core metrics including network, storage and virtual machines. You would be happy to know about new command line utility VSANTOP – that runs on ESXi hosts to view the real time vSAN performance metrics. You can use this tool to monitor vSAN performance. This tool is designed for Advance VMware Engineers and vSAN Support team to measure performance metrics of vSAN cluster.
As of today documentation available on this tool is limited and explanation of metrics is not involved in the same, but I have played around with this tool in my lab.
You can find the VMware documentation here https://bit.ly/2k4I37s
You can use this tool by following the below procedure:
- Take SSH session of any vSAN ESXi Host
- Type “VSANTOP” and hit Enter
- It will display the UI with default entity type “host-domclient”
Above screenshot is the default UI of vsantop. It shows entity type: host-domclient (which is actually local ESXi node). You can do lot with vsantop but you should know all the options to play with.
Let’s check one by one what all we have here according to official documentation.
In order to display the different performance views and metrics in vsantop, enter the following commands:
|h or ?||Help; show this text|
|f/F||Add or remove fields|
|o/O||Change the order of displayed fields|
|s||Set the delay in seconds between updates|
|#||Set the number of instances to display|
|E||Change the selected entity type|
|L||Change the length of the field|
|l||Limit display to specific node id|
|.||Sort by column, same number twice to change sort order|
To move further and choose other entity type press key E and you will see below metrics. You can choose entity type by typing the number from 1-40.
You can also look for different-2 fields for each entity type. Below is the example of all the fields available under entity type: host-domclient. The * displays that they are already visible in the UI and you can select between 1-32 to make additional fields visible. You can maximum select 10 at one point of time so you have to remove the existing field and select the required one.
From my lab I am showing some metrics as an example for entities like:
The table will be refreshed automatically by every collect interval. Users can set the delay in seconds between updates by press key “s”.
VSANTOP version and help information:
Hit h or? in order to get the below screen
Let’s talk about “^L” which references to field size here as an example:
You can increase the size of columns or fields (any way you would like to understand). In below screenshot it is already set to 10.
Reset field size to 20 by pressing key ^L in help menu
After pressing Enter key, fields have been resized.
Take another example of “oO” symbol used to change the order of displayed fields:
Go to below screen by pressing h or?
Press oO and you get below screen
With above screenshot, it is clear you can process alphabets a-j in order to change the order of the fields. You can see below example; I have changed for some.
I hope this article has given you some idea about vsantop. Once official documentation is available in storage hub, I will try to explain more stuff.