Before you begin it is important to realize that vSAN is a software based storage product that is entirely dependent on the proper functioning underlying hardware components, like network, storage I/O controller and the individual storage devices. You always need to follow the vSAN Compatibility Guide for all deployments. I often play with things in my homelab, just because you CAN do it, doesn’t mean it’s supported by VMware. 🙂
I’ve recently been playing with stretched clusters in my homelab and have finally had to fix some of the stuff I’ve been playing with. The beauty of the homelab, is I can break anything I want! I had not worked with the Ruby Console at all but it’s an amazing tool to check out.
Many vSAN errors can be traced back to faulty VMkernel ports, mismatched MTU sizes, etc. It’s far more than simple TCP/IP.
Some of the tools you can use to troubleshoot vSAN are:
- vSphere Web Client
- The primary tool to troubleshoot vSAN.
- Provides overviews of individual virtual machine performance.
- Can inspect underlying disk devices and how they are being used by vSAN.
- esxcli vsan
- Get information and manage the vSAN cluster.
- Clear vSAN network configuration.
- Verify which VMkernel network adapters are used for vSAN communication.
- List the vSAN storage configuration.
- Ruby vSphere Console
- Fully implemented since vSphere 5.5
- Commands to apply licenses, check limits, check state, change auto claim mechanisms, etc.
- See this link for a great introduction to RVC.
- vSAN Observer
- This tool is included within the Ruby vSphere Console.
- Can be used for performance troubleshooting and examined from many different metrics like CPU, Memory or disks.
- Third Party Tools
I also highly recommend checking out the vSAN troubleshooting whitepaper the Cormac Hogan has written: