Test-Computer

I am working on an automated SQL Server installation, where we use Managed Serviece Accounts (MSA) as SQL Server service account. To create and configure a MSA some PowerShell CmdLets are given by Microsoft, but there are several steps each with it own CmdLets.
We are creating MSAs for a given computer that is used as SQL Server server, and we want to absolutely sure that the computer exists by a given name in Active Directory (AD)and DNS. That also includes that the Fully Qualified Domain Name (FQDN) is correct.
To do this check I have created a function that checks both AD and DNS. The function is constructed to a specific script, and you should probably alter something to make it suit your needs.

function Test-Computer {
[CmdletBinding()]
Param(
  [Parameter(Mandatory=$true, HelpMessage='Enter name of server. Use Fully Qualified Name (FQN), e.g. "SANDBOX.sqladmin.lan"')]
  [String]$ServerName
)

[String]$ComputerName = $ServerName.Split('.')[0]

"{0:s}Z Testing if the computer '$ComputerName' exists in DNS..." -f $([System.DateTime]::UtcNow) | Write-Verbose
try {
  [System.Net.IPHostEntry]$IpHost = [System.Net.Dns]::GetHostByName($ComputerName)
}
catch [System.Management.Automation.MethodInvocationException] {
  "'$Computername' does not exist in DNS as FQDN!"
  return $false
}
"{0:s}Z Testing if the FQDN of '$ServerName'..." -f $([System.DateTime]::UtcNow) | Write-Verbose
if ($IpHost.HostName -ieq $ServerName) {
  "{0:s}Z FQDN '$ServerName' is OK." -f $([System.DateTime]::UtcNow) | Write-Verbose
}
else {
  "The computer name '$ServerName' does not match the FQDN '$($IpHost.HostName)'." | Write-Error
  return $false
}

"{0:s}Z Testing if the computer '$ComputerName' exists in Active Directory..." -f $([System.DateTime]::UtcNow) | Write-Verbose
try {
  [Microsoft.ActiveDirectory.Management.ADComputer]$Computer = $null
  $Computer = Get-ADComputer -Identity $ComputerName
}
catch [Microsoft.ActiveDirectory.Management.ADIdentityNotFoundException] {
  $ComputerError = $Error[0]
}
if ($Computer) {
  "{0:s}Z The computer '$ServerName' exists in Active Directory." -f $([System.DateTime]::UtcNow) | Write-Verbose
  return $true
}
else {
  "The computer '$ServerName' does not exist in Active Directory." | Write-Error
  return $false
}

} # Test-Computer()