$optional = [ 'groupLoadsBySection', 'groupLoadsByDB', 'hostsByName',
'externalLoads', 'externalTemplateOverrides', 'templateOverridesByServer',
'templateOverridesByCluster', 'templateOverridesBySection', 'masterTemplateOverrides',
$optional = [ 'groupLoadsBySection', 'groupLoadsByDB', 'hostsByName',
'externalLoads', 'externalTemplateOverrides', 'templateOverridesByServer',
'templateOverridesByCluster', 'templateOverridesBySection', 'masterTemplateOverrides',