#ESXi server being targeted
$target = Read-Host "Target host"

Disconnect-VIServer -Confirm:$false
#$creds | Get-Credential
Connect-VIServer -Server $target -User root -Password PCSuser01.13

$vms = Get-VM -Location $target -Name *
#$dStore = Get-Datastore -Name *OS* -Server pcs-lab2h1.cenet.coned.uah.edu

####This is only here is you want it to happen well after the script is started
####Added the still waiting just for some confirmation that it is running
####Adjust time or comment out as needed
for($i=1; $i -le 5;$i++)
{
    Write-host "Still waiting......"
    Start-Sleep -Seconds 3600 -Verbose
}

foreach ($vm in $vms)
{
    if($vm.PowerState -eq "PoweredOn")
    {
            Shutdown-VMGuest $vm.Name -Verbose -Confirm:$false
            do
            {
                Start-Sleep -s 5 -Verbose
                Write-Host "Sleeping 5"
                $vm = Get-VM $vm
            }
            until($vm.PowerState -eq "PoweredOff")
    }
}

$targetHost = Get-VMHost -Server $target #problem here or below

Set-VMHost -State Maintenance -Confirm $false #-Server ####problem with server name

while($targetHost.ConnectionState -ne "Maintenance")
{
    Start-Sleep -Seconds 5 -Verbose
    $targetHost = Get-VMHost -Server $target -Verbose
    Write-Host "Waiting for host to enter maintenance mode"
}

Restart-VMHost -Confirm $false -Verbose

Start-Sleep -Seconds 500 -Verbose

while(!(Test-Connection pcs-esxi1 -Count 1))
{
    Start-Sleep -Seconds 5 -Verbose
    Write-Host "Waiting for pingback"
}

Set-VMHost -State Connected -Verbose

while($targetHost.ConnectionState -ne "Connected")
{
    Start-Sleep -Seconds 5 -Verbose
    $targetHost = Get-VMHost -Server $target
    Write-Host "Waiting for server to exit maintenance mode"
}

#turn the VMs that were previously on back on
foreach ($vm in $vms)
{
    Start-VM $vm.Name -Verbose -Confirm:$false -Verbose
}