Use the following CLI to get the state of your ESX hosts, the cpu and memory usage:

t-Datacenter | Sort | Get-VMHost | Sort | Get-View |`
Select Name, OverallStatus, `
@{N="CPU Usage (GHz)";E={[math]::round(
$_.Summary.QuickStats.OverallCpuUsage/1024,2)}}, `
@{N="Memory Usage (GB)";E={[math]::round(
$_.Summary.QuickStats.OverallMemoryUsage/1024,2)}}

Add line 7 to it to get all status except green:

Get-Datacenter | Sort | Get-VMHost | Sort | Get-View | `
Select Name, OverallStatus, `
@{N="CPU Usage (GHz)";E={[math]::round(
$_.Summary.QuickStats.OverallCpuUsage/1024,2)}}, `
@{N="Memory Usage (GB)";E={[math]::round(
$_.Summary.QuickStats.OverallMemoryUsage/1024,2)}} | `
Where { $_.OverallStatus -ne "green" }

source: http://laez.nl/quick-and-simple-vmware-esx-host-statistics/