get-DomainAdminLastLogon

get-DomainAdminLastLogon.ps1

$domainControllers = Get-ADDomainController -Filter * 

Get-ADGroupMember -Identity 'Domain Admins' -Recursive | ForEach-Object -Process {
    $user = $_
    $domainControllers |
    ForEach-Object -Process {
        Get-ADUser $user.SamAccountName -Server $_.Name -Properties lastLogon, cn, employeeNumber, accountExpires, PasswordNeverExpires, Enabled, LockedOut, pwdLastSet
    } |
    Sort-Object -Property LastLogon |
    Select-Object -Last 1 -Property SamAccountName, 
                            @{ name = 'LastLogon' ; expression = { [DateTime]::FromFileTime($_.LastLogon) } }, 
                            cn, employeeNumber, 
                            @{ name = 'accountExpires' ; expression = { [DateTime]::FromFileTime($_.accountExpires) } },
                            PasswordNeverExpires, Enabled, LockedOut, 
                            @{ name = 'pwdLastSet' ; expression = { [DateTime]::FromFileTime($_.pwdLastSet) } }
} | Export-Csv .\banana.csv

Gets real last logon time for every domain admin by interrogating every DC.