Protect OU (Organizational Unit) in AD from accidental deletion

to verify if your OUs are protected from accidental deletion use:

Get-ADOrganizationalUnit -Filter * -Properties * |Select-Object DistinguishedName, ProtectedFromAccidentalDeletion


to protect all OUs in AD from accidental deletion use:

Get-ADOrganizationalUnit -Filter * | Set-ADObject -ProtectedFromAccidentalDeletion:$true

Find FSMO roles from powershell

Get-ADDomainController -Filter * | Select-Object Name, Site,  OperatingSystem, OperationMasterRoles

Search eventlogs with xml filter

# 4625 bad password in client log
# 4771 bad password in DC log
# 4740 lockout in DC log
# <Select Path="Security">*[System[(EventID=4740 or EventID=4771)]]</Select>

[xml]$XMLFilter = @"
<QueryList>
  <Query Id="0" Path="Security">
    <Select Path="Security">*[System[(EventID=4740)]]</Select>
  </Query>
</QueryList>
"@

$AllDomainControllers = Get-ADDomainController -Filter *

$AllEvents = @()

foreach($DC in $AllDomainControllers){
    $Events = @()
    $Events += Get-WinEvent -FilterXml $XMLFilter -ComputerName $DC.HostName -ErrorAction SilentlyContinue
    $AllEvents += $Events
    $DC.HostName + ' ' + $Events.Length
}

foreach($Event in $AllEvents){
    $EventXMLData = [xml]$Event.ToXml()
    for($i=0; $i -lt $EventXMLData.Event.EventData.Data.Count; $i++){
        $Name = $EventXMLData.Event.EventData.Data[$i].Name
        $Value = $EventXMLData.Event.EventData.Data[$i].'#text'
        Add-Member -InputObject $Event -MemberType NoteProperty -Force -Name $Name -Value $Value
    }
}

$AllEvents |
Select-Object TargetUsername, MachineName, TimeCreated,IpAddress, ID |
Format-Table

Active directory domain user last logon date and time

"lastLogon" attribute is per domain controller - is not replicated to other domain controllers in the domain and each domain cotroller has his own information.

"lastLogonTimeStamp" is replicated in the domain (all domain controllers have the same updated information).

the date is stored in 100 miliseconds interval since 01.01.1601 (Juanuary 1, 1601)

to convert from System.Int64 we can use "FromFileTime" static method of DateTime class:

[System.DateTime]::FromFileTime($ADUser.lastlogon)
[System.DateTime]::FromFileTime($ADUser.lastlogontimestamp)

http://msdn.microsoft.com/en-us/library/ms676824(VS.85).aspx
http://msdn.microsoft.com/en-us/library/ms676823(VS.85).aspx

Active Directory Technical Specification

search the web for "MS-ADTS"

https://msdn.microsoft.com/en-us/library/cc223122.aspx

List active directory group membership changes

$ADGroup = Get-ADGroup -Identity 'Domain Admins'
Get-ADReplicationAttributeMetadata -Object $ADGroup.DistinguishedName -Server dc1 -ShowAllLinkedValues

in the output the "AttributeName" is the attribute that was changed - we should search for the "member" attribute.

"AttributeValue" is the value assigned to the attribute.
"FirstOriginatingCreateTime" is the time the value was added.
"LastOriginatingDeleteTime" is the time the value was deleted - but only if is different from "1/1/1601 2:00:00 AM"