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Get-ADDomainController - AD Cmdlets Reference


Get-ADDomainController is useful to easily return all, or a subset of your domain controllers.  This can be easily filtered by type, OS, AD Site, or a number of other values.

Example usage

#get all read only DC's
Get-ADDomainController -filter {isreadonly -eq $true}
# get the domain controller DC1
Get-ADDomainController -identity "DC1"
# get the PDCE for the domain
Get-ADDomainController -Discover -Service "PrimaryDC"}
# get a GC but force it to rediscover (clear any cached DC)
Get-ADDomainController -Discover -Service "GlobalCatalog" -ForceDiscover

Define the parameters

Identity takes a range of identifiers for the object. These include "Distinguished Name", "GUID", "SID", and "samaccountname".

Service takes the following :
PrimaryDC or 1
GlobalCatalog or 2
KDC or 3
TimeService or 4
ReliableTimeService or 5
ADWS or 6

Filter uses the format {isreadonly -eq $true} against most of the object properties.

There are more options, use get-help cmdlet for all options

In a script

For each Read / Write DC, tell me how much memory the lsass process is using in Mb.
foreach ($RWDC in $(Get-ADDomainController -filter { isreadonly -eq $false })) {
   $lsass = get-process -ComputerName $ -Name lsass
   "Current memory usage for lsass on $($ is $($lsass.WorkingSet / 1mb)Mb"

Powershell without the Management pack
I have covered How to find a GC, here are some others :

#get all DC's in the domain
$domain = [System.DirectoryServices.ActiveDirectory.domain]::getcurrentdomain()

#read only DC's
#search AD for DC's with a primary group ID of 521
#or get memebers of the group "Enterprise Read-only Domain Controllers"

#get pre-staged RODC objects
#search AD and filter DC's for useraccountcontrol value of 83890178


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