Get the NetBIOS AD Domain Name from the FQDN

I hate using NameTranslate, because it is a COM object, and because the output is often really hard to get into a clean, trimmed string.  The netBIOS name isn’t a part of the AD domain object, but I suspected that the information could be gotten using a LDAP query.  My searching lead me to a post on StackFlow.  It wasn’t PowerShell, but it did give me an interesting hint.  The filter’s objectcategory was “CrossRef”.  I used this to port the code to PowerShell:

Function Get-DomainNetBIOSNameFromDNSName ($DomDNS){
    $objRootDSE = [System.DirectoryServices.DirectoryEntry] "LDAP://rootDSE"
    $ConfigurationNC= $objRootDSE.configurationNamingContext
    $Searcher = New-Object System.DirectoryServices.DirectorySearcher 
    $Searcher.SearchScope = "subtree" 
    $Searcher.PropertiesToLoad.Add("nETBIOSName")| Out-Null
    $Searcher.SearchRoot = "LDAP://cn=Partitions,$ConfigurationNC"
    $searcher.Filter = "(&(objectcategory=Crossref)(dnsRoot=$domDNS)(netBIOSName=*))"
    ($Searcher.FindOne()).Properties.Item("nETBIOSName")
}

This query is quick, and avoids the formatting problems with NameTranslate.  There is a large table of LDAP queries on TechNet, but this one isn’t in the list.