At the moment, Delta discovery seems to be causing more issues than benefits. I'm regularly getting the following issue: http://blogs.technet.com/b/configmgrteam/archive/2011/09/09/known-issue-and-workaround-duplicate-records-when-you-use-unknown-computer-support-with-active-directory-delta-discovery.aspx Mainly when building machines with OSD and entering the AD object into a security group for software deployment. Its not working as there are 2 seperate objects etc. Does Delta Discovery have any benefits in a small environment (1500 PCs) which will force me to keep it enabled?

Hi, In such a small environment you can probably tweak the System Group discovery to run as often as possible instead, which will work much better. You can probably turn off System Discovery as well if you install all computers using SCCM.. Regards, Jörgen-- My System Center blog ccmexec.com -- Twitter @ccmexec

Notice that delta discovery in CM07 only works for new objects, meaning that you still need to run a full discovery every now and then to get up-tp-date information in existing objects that are moved/removed from AD groups.Kent Agerlund | My blogs: blog.coretech.dk/kea and SCUG.dk/ | Twitter: @Agerlund | Linkedin: Kent Agerlund

OK, so If I turned off Delta discovery, but forces System Group Discovery to run more often I would not get the duplicate entries, and would still have a speedy software deployment based on AD Group membership? Is System Group Discovery the process by which the membership of AD Groups is discovered? If I turn off System Discovery then all machines will need the clients either installing manually or as part of the OSD Task Sequence?

You will not get ride of duplicate entries just by turning off Delta discovery. It's not the delta process but the AD system Group combined with AD System discovery that can cause duplicate entries. Yes, AD System Group discovery will discover the machine group memberships.Kent Agerlund | My blogs: blog.coretech.dk/kea and SCUG.dk/ | Twitter: @Agerlund | Linkedin: Kent Agerlund

Also, you can use below collection query to find out duplicate records Select R.ResourceID,R.ResourceType,R.Name,R.SMSUniqueIdentifier,R.ResourceDomainORWorkgroup,R.Client from SMS_R_System as r full join SMS_R_System as s1 on s1.ResourceId = r.ResourceId full join SMS_R_System as s2 on s2.Name = s1.Name where s1.Name = s2.Name and s1.ResourceId != s2.ResourceId and R.Client = nullAnoop C Nair - @anoopmannur MY BLOG: http://anoopmannur.wordpress.com User Group: ConfigMgr Professionals This posting is provided AS-IS with no warranties/guarantees and confers no rights.

This is my current setup: AD System Group Discovery - enabled, runs every 30 mins AD Security Group Discovery - enabled, runs every 60 minsAD System Discovery - enabled, runs every 1 day AD User Discovery - disabled Heartbeat Discovery - enabled, runs every 7 days Network Discovery - enabled, Topology, Client and OS, on Local Domain and Local Subnet, runs every 7 days We have two seperate 'worlds' at the moment, New World machines get their client installed as part of the OSD Task Sequence, Old World machines have their client pushed - I think. I don't mind bringing the Old World up to the same level as New World and forcing the guys to manually install the client if need be - i.e. I think I'd need to if I disabled System Discovery, Yes? What would you advise to enable, disable, change time etc?