When you have a lab it is very wise to have a UPS that will protect you in case of a power shortage, this is because a power shortage can bring everything down. When everything is 100% virtualized, DHCP , DNS and active directory. Recovering this type of environment is a little hard from a complete outage. This is because after you have brought the network, storage and ESXi hosts online. Still the DHCP will not be on, from which you leverage to open the vSphere Client and connect to an ESXi host. What this means is that you bring up a few infrastructures VMs from the ESXi host TSM(Tech Support Mode ) console. This can be done using the vmware-cmd
On ESXi 5.0 update 1, vmware-cmd does not work. The command has been deprecated and replaced by /usr/bin/vim-cmd.
Before starting infrastructure VMs using vim-cmd, first find the corresponding Vmid using vim-cmd vmsyc/getallvms ( add more at the end to pause at each page of a long list of registered virtual machines ).
You can now power on using this command vim-cmd vmsvc/power.on 77 you have the DHCP and you can use the vSphere Client on my workstation to power up the remaining virtual machines. This can also be done using the vim-cmd. When you have done that you will see how much more can be done using the vim-cmd from the output you will see. Try this in your own lab. This can come in handy when tackling VCAP-DCA exams. This will also help you during a power outage.