FSMO role holders and domain and forest functional levels

#Requires -Modules ActiveDirectory
# FSMO role holders and functional levels for this domain and its forest. Read-only.

$domain = Get-ADDomain
$forest = Get-ADForest

[pscustomobject]@{
    Forest               = $forest.Name
    ForestMode           = "$($forest.ForestMode)"
    SchemaMaster         = $forest.SchemaMaster
    DomainNamingMaster   = $forest.DomainNamingMaster
    Domain               = $domain.DNSRoot
    DomainMode           = "$($domain.DomainMode)"
    PDCEmulator          = $domain.PDCEmulator
    RIDMaster            = $domain.RIDMaster
    InfrastructureMaster = $domain.InfrastructureMaster
}

Checked automatically against Microsoft's published cmdlet reference. KBY hasn't run it in your tenant; run it in a test environment first.

Where to run it

A domain-joined machine with the Active Directory module (RSAT) installed.

Reading the output

• PDCEmulator, RIDMaster and InfrastructureMaster are per domain (from Get-ADDomain); SchemaMaster and DomainNamingMaster are per forest (from Get-ADForest).
• Run it in each domain of a multi-domain forest to see every domain's role holders and level.
• A role holder that names a domain controller you have retired is a sign the role was never moved.

Sources

The Microsoft reference page for every cmdlet the script calls, plus the API and product pages behind each permission and caveat.