ESX/ESXi Bookmarks

• vmkperf - Monitor hardware performance events 
• Performance community documents for VMark
• Interpretting esxtop
• PVSCSI - VMWare ParaVirtual SCSI adapter 
• Network adapters 
• vSphere Online Library - ESX/vCenter v4.1

Clone VM in ESX without vCenter

Login to the ESX/ESXi console to clone vm1 datastore to vm2. 


$ cd /vmfs/volumes/datastore/
$ mkdir vm2
$ vmkfstools -i vm1/vm1.vmdk vm2/vm2.vmdk


Next, create vm2 from the client GUI and choose existing disk option pointing to the newly created vm2.vmdk. 


More details available in the excellent article here.


To read how to access the hidden ESXi console, refer to this article.

Could not power on VM : No space left on device - Failed to power on VM

With VMWare's ESX or ESXi, "Could not power on VM : No space left on device - Failed to power on VM" is a common sight when trying to start a VM.

This error seems bizarre especially when you are actually trying to increase the guest RAM and the error is about disk space. The cause could be the following:

1. By default, ESX will configure a swap on the VM's datastore equal to the RAM. So, when RAM is increased, more disk space is required. The fix is to reserve memory in resource allocation settings for the VM.
   
2. There really isn't enough disk space on the datastore. Reduce Hard Disk size for the VM.