Hello,

By design, Active Directory Global Catalog Domain Controllers replicates more attributes to each other (between the same forest) than to others Domain controllers (No GC, local domain). Those attributes replicated between global catalog of the forest are called “Partial Attributes Set” (PAS), and you can  see those with the schema mmc :

The PAS is configured by the case “Replicate this attribute to the Global Catalog”.

As usual, you can find all of those attributes with PowerShell :

#GC Attributes
$dse = [adsi]“LDAP://RootDSE”
$SchemaPart=$dse.schemaNamingContext
$GCAttSearcher=[ADSISearcher]"(&(objectCategory=attributeSchema)(isMemberOfPartialAttributeSet=TRUE))"
$GCAttSearcher.SearchRoot=[adsi]"LDAP://$SchemaPart"
$GCAttSearcher.FindAll() | Select-Object -ExpandProperty Path | % {($_ -split ",")[0]} | % {($_ -split "=")[1]} | Sort-Object