Johnny Zhang
There are times when we need to test on all vmkernel network connections. It's own vmkernel interface, iSCSI network, NFS mounts, vmkernel network gateway. You can use one command to ping them all at once

vmkping -D

Johnny Zhang
There are times we need to find out information about the physical network cards.
We all know how to list the NICs by using:

esxcfg-nics -l
Now we know we have two physical NICs. vmnic0 and vmnic1. what about if I want to know more information about them? The command ethtool will help us.

ethtool -i vmnic0
This will give us the driver version and the firmware level this NIC is currently at. You still want more information?

ethtool vmnic0
netstat -int
Will give you information on the health of your physical NICs' packets receive and transmit
Johnny Zhang
How do you know if your virtual machine's configuration file (vmname.vmx) is good? You might not find the typo in there by looking at it. And what about you have 30, 40, 50 of them on this host? You can run one command to do a quick check for you
This command will go through all the steps necessary to power on a VM. Once it finish with all the steps it will give the VM a "PASS" tag. If you have problem with the configuration file. The problem VM will taged as "FAIL"
Johnny Zhang
Many times, we need to find storage information on ESX servers when work with the storage teams. 'vmware-vim-cmd' commands can help us to pull those information quickly
There are many useful information we can pull out from 'vmware-vim-cmd' commands. I will list three of them here.

1. vmware-vim-cmd "hostsvc/summary/fsvolume"

This command will link your data store's friendly name with the path and the LUN Ids. It will also allow you to verify the file system type and if any of them went read only on you.

2. vmware-vim-cmd "hostsvc/summary/hba"
This command gives information on the physical HBA's PCI Ids, currently used driver, model and speed.

vmware-vim-cmd "hostsvc/summary/scsilun"
This is extremely useful since the UUID out put from this command is what the SAN team really understand.