adSiteName = (Get-ExchangeServer $RoleFqdnOrName -DomainController $RoleDomainController).Site.Name; $externalServiceFqdn ...

$adSiteName = (Get-ExchangeServer $RoleFqdnOrName -DomainController $RoleDomainController).Site.Name;          $externalServiceFqdn =  $adSiteName + ".um.prod." + $RoleDatacenterSiteName;          Write-ExchangeSetupLog -Info "Setting ExternalServiceFqdn to '$externalServiceFqdn'";                Set-UMService -Identity $RoleFqdnOrName -ExternalServiceFqdn $externalServiceFqdn -DomainController $RoleDomainController;