Local Machine vs. Domain Group Policy

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I want our network admin to create an OU for Terminal Services and give me
admin rights to it so I can create a "lockdown" GPO, link it to the OU and
add a Terminal Server computer to this OU. The new GPO would include a deny
apply exception for administrator accounts. This is a best practices approach
for Terminal Services.

Our network admin does not want to create an OU and give me rights to it.
Instead he wants me to create group policies on the local machine. Since we
only have one TS at this time, I agreed. But is this approach feasable?

I've got Group Policy Management Console with admin rights on the Terminal
Server and I can see domain level group policy objects. Can I create a new
GPO using GPMC and link it to to a local machine? I understand how to use
gpedit.msc on the local machine, but in that tool I don't know how to create
"deny apply" exceptions for admin accounts.
 
mg said:
I want our network admin to create an OU for Terminal Services and give me
admin rights to it so I can create a "lockdown" GPO, link it to the OU and
add a Terminal Server computer to this OU. The new GPO would include a deny
apply exception for administrator accounts. This is a best practices approach
for Terminal Services.

Our network admin does not want to create an OU and give me rights to it.
Instead he wants me to create group policies on the local machine. Since we
only have one TS at this time, I agreed. But is this approach feasable?

No, for at least two reasons.

Your network admin is missing GPO processing order, which may result
with overwriting local setting by GPO settings placed on the domain or
OU level.

Second is manageability - what if You will have second or third TS
server? Why make it harder now and repeat th work when You will increase
number of the machines instead of doing this once but good.

And remember about loopback processing mode if you want to lock down TS
environment
I've got Group Policy Management Console with admin rights on the Terminal
Server and I can see domain level group policy objects. Can I create a new
GPO using GPMC and link it to to a local machine? I understand how to use
gpedit.msc on the local machine, but in that tool I don't know how to create
"deny apply" exceptions for admin accounts.
No, You can't link domain GPO to the local machine - If You want to use
local policy You have to configure it on the machine
 
Tomasz, thank you very much for your time and expertise. All the information
I've received agrees with your characterization of the situation.

However, our network admin is very difficult to reason with even when he's
on shakey ground. I would certainly agree that a local policy solution is
impractical and inefficient, but it sounds like I can't go to this guy and
say it absolutely won't work right?

Even if local policy could work, I'm not sure how to create a "deny apply"
exception for administrators logging into the Terminal Server using the
gpedit.msc snap-in.

BTW, his latest excuse is that any changes to AD can lead to registry
corruption on the domain controller. That argument can be made about any
Windows computer! Isn't that what registry and GPO backups (perhaps using the
new GPMC) are for? Anybody looking for a network admin? I'll sell him cheap.
[LOL]
 
mg said:
Tomasz, thank you very much for your time and expertise. All the information
I've received agrees with your characterization of the situation.

However, our network admin is very difficult to reason with even when he's
on shakey ground. I would certainly agree that a local policy solution is
impractical and inefficient, but it sounds like I can't go to this guy and
say it absolutely won't work right?

Even if local policy could work, I'm not sure how to create a "deny apply"
exception for administrators logging into the Terminal Server using the
gpedit.msc snap-in.

For local policy You can create deny apply exception using NTFS
permissions on the policy files or using this KB:
http://support.microsoft.com/default.aspx?scid=KB;EN-US;293655

BTW, his latest excuse is that any changes to AD can lead to registry
corruption on the domain controller. That argument can be made about any
Windows computer! Isn't that what registry and GPO backups (perhaps using the
new GPMC) are for? Anybody looking for a network admin? I'll sell him cheap.
[LOL]
Sorry that I'm saying that because I don't this guy and I'm far from
judging the people but maybe You should make a serious talk with him.
 
Tomasz Onyszko said:
mg wrote:
For local policy You can create deny apply exception using NTFS
permissions on the policy files or using this KB:
http://support.microsoft.com/default.aspx?scid=KB;EN-US;293655

And there is also a (registry) setting that will allow
a domain machine's own settings to override those
from the GPOs of the domain, but it is a very poor
practice to use this.

Also, in some sense, no matter how 'unreasonable' the
admin is (or isn't) such things are really HIS/HER job
to get right and when we discuss ways to defeat admin
control we are really working counter to the design of
the Windows systems.

(Doesn't mean it won't work, but educating the admin
should be the first step WHEN possible.)

[I once had to use the registry override for a dedicated
(rental) web server where the ISP was providing a
"medium" security setting becaused so many of their
customers were unaware of a particular issue AT ALL,
but I wanted to have HIGH security setting and their
medium would override my high by default.]

--
Herb Martin, MCSE, MVP
Accelerated MCSE
http://www.LearnQuick.Com
[phone number on web site]

BTW, his latest excuse is that any changes to AD can lead to registry
corruption on the domain controller. That argument can be made about any
Windows computer! Isn't that what registry and GPO backups (perhaps using
the new GPMC) are for? Anybody looking for a network admin? I'll sell him
cheap. [LOL]
Sorry that I'm saying that because I don't this guy and I'm far from
judging the people but maybe You should make a serious talk with him.
 
Tomasz, I'm only kidding about selling the network admin. I don't have that
kind of power so we're stuck with him. But there have been many incidents
like this that have more to do with control than the best way to do
something. I'll probably end up having to try a local policy solution because
he's the only one with AD admin rights and he wants to keep it that way. He
doesn't have time to impliment this badly needed solution himself so just
block anyone else is typical behavior for him.

Thanks for your help.
 
Herb, I agree in general we need to educate when possible. This will be an
extremely slow and difficult process in this case because we have someone who
believes they are more expert than anyone else including Microsoft when in
fact they lack experience and knowledge in this area. I've already had to
overcome completely bogus objections to the standard/best practices approach
to this issue--objections such as an OU/linked GPO solution will hurt network
performance and making any changes to Active Directory might corrupt it
(Maybe we should just shut all the computers off to completely avoid this!),
etc.

But that last objection will at least open the for the CIO to ask if he is
backing up the domain controller(s) adequately which I doubt.
 
To offer a counter viewpoint to some of those expressed, I have in the past and
wouldn't be surprised in the future to have the same viewpoint of your admin.
Lots of people like to think that GPOs are the panacea and they quite frankly
are not, I have had to deal with mad levels of issues with GPOs over the years.
In a single TS Server environment or even one with 40 I wouldn't hesitate to
tell you to use local settings versus slapping a ton of new policies in the
directory that I now have to make sure replicate properly and work.

I absolutely WOULD not give you full control over an OU. At best I might allow
you to create a machine account but most likely I wouldn't even do that and
instead create machine accounts and allow you to join them.

These are things I did in a Fortune 5 company and they worked very well. We had
TS servers all over the world and not a single GPO specific to them. There were
only 6 user GPOs and 6 Workstation GPOs and then the two builtin GPOs.
Everything else was managed and managed well with local security policy.

joe

--
Joe Richards Microsoft MVP Windows Server Directory Services
Author of O'Reilly Active Directory Third Edition
www.joeware.net


---O'Reilly Active Directory Third Edition now available---

http://www.joeware.net/win/ad3e.htm
 
Joe, counter viewpoints may serve to teach us something. This is indeed
counter to all the responses so far in the Terminal Services, Group Policy
and Active Directory newsgroups and counter to what Microsoft recommends.
That doesn't prove anything as to the validity of your view and your
credentials are nothing to sneeze at either.

That being said, I can understand the advantages of the OU with linked
domain GPO solution. A Citrix solution already deployed in our domain uses
this approach. To understand your alternative approach it would help to
clarify a couple of points.

I researched, installed, configured and tested this TS solution. I have
admin rights to the server and I'm also the application administrator and
DBA. The only thing remaining is to lock TS down before deployment. Our
network admin does not have TS knowledge or experience. Being an understaffed
IT shop, he also has little time to devote to this critical deployment.

I'm proposing that he give me control of a single GPO so I can build the
lockdown policy. Once that is done, the network admin would review the GPO,
create the OU, link the GPO move the TS computer into the OU, then we test.
Once testing is completed and we're deployed I don't care who has control
over the OU or GPO. He can have sole control of it all, although I will say
this could slow us down if the policy requires post-deployment tweaking.

With that on the table, it would help me a lot if you would clarify a couple
of points:

1. Using local policy, is there some easy way to copy it to other machines,
or are you suggesting building and testing this complex lockdown policy 40
times (as in your 40 TS example)? Wouldn't future changes also have to be
applied 40 times?

2. We're talking about one GPO and one OU. I'm responsible for the TS
solution and applications that go into this OU. AD is designed to let the
domain admin delegate permissions to a specific OU and GPO and the person
delegated to cannot affect anything else in the domain right? Given that the
domain admin will review everything before deployment and can always unlink
or otherwise modify the GPO or revoke permissions, can you explain or provide
any specific reason why you would still refuse to delegate permissions?

When I try to understand your viewpoint based on what's been said so far, it
sounds like your motivation is to avoid hassle and potential problems (having
to review the policies, make sure they replicate properly, etc.) for the AD
admin by blocking use of AD altogether whenever possible. I can see where
domain admins would love this approach. <g> Also, maybe replication was a
bigger issue for this global client than it would be for us.

Please don't get upset with me if I'm way off base here. I'll be happy to
learn from and humbly accept a methodical dismantling of my misperceptions.
Thanks for your input on this interesting discussion.
 
The first item I will respond to is full control over an OU. It is too much
power. It allows you to create any object under that OU that is allowed to be
created under an OU because you have the ability to manipulate the SD. I rarely
if ever recommend giving full control to anything in AD to anyone but full
domain admins, of which, I recommend you not have more than 5 or 6 of for an
entire forest regardless of company size.

AD has many security issues and while delegation is nice there are lots of
shortcomings in it including no business rules/triggers and painful/poor logging.

I highly recommend using vetted provisioning/metadata processes that incorporate
business rules/triggers and great logging such as Quests AR Server or MIIS or
HP's LDSU and not allowing admins to directly modify the directory. In my
discussions with MS about adding some functionality to help counter this the
responses from the highest levels of management of the development groups for
DS/IdM tell me the idea is that people should be using metadata/provisioning
products for all management of AD. MS, at least the current program managers
over Identity Management and Directory Services all indicate that AD is
basically a back end store at this point.



On the point of the TS policies, it has been several years since I have had to
work on that as I have since moved into consulting, but yes you can come up with
local policy templates and apply them. In fact, at the customer mentioned (go
hunt down my resume and the customer will be obvious) we put together a setup
where you specified the role of the server during the build process and the
appropriate security policy was stamped onto the machine at that point. The only
domain policy that was applied to the machines was the default domain policy
which only defined password policy and policy that applied specifically to users
in the domain. There is a lot of power there, I just recall it was documented
poorly because someone wanted to push using Domain based policy but that is
mostly due to workstation management, not server.

One of my concerns with domain based policy is that it gets out of control. You
start with one, you end up with 200 to meet any special little needs of every
little occasion. It becomes a train wreck to manage and I walk into customers
all of the time that have many policies that they have no idea is for, what they
do, whether or not they are actually being used, why certain things aren't
working, etc.

Another concern is that it is very easy to hurt many machines/users very quickly
with a single mistake in a domain based policy. I once saw some 200k users all
get locked down to kiosk mode in the space of 30-40 minutes because of one small
ACL issue on a policy. This was because it was using group based filtering which
I WAY don't recommend but the idea is the same, one small mistake becomes a huge
issue that may or may not be easy to back yourself out of.

Another concern is, as you indicated, hassle of dealing with it from a domain
admin level. Microsoft in its infinite wisdom chose to use two entirely
different replication engines to move GPOs around a domain. This means you have
two entirely different replication engines and sets of data to watch over for
convergence. If you use a very minimal set of policies that never change then
you can pretty much stop worrying about one of those replication mechanisms
except during the addition of new DCs. If you allow someone outside of the 3-4
domain admins to modify policy, you now have to track everytime they make a
modification and make sure that is replicating fine.

Another concern is for local admins. In my position I mentioned previously, I
dealt with literally thousands of local site admins, one of their main issues
with AD is the lack of control that they had when they had local resource
domains. Domain based group policy is a big part of that because it is something
that no longer impacts just them. Things they do now have more far reaching
impact on who has to deal with it and when troubleshooting, they often are not
self-sufficient and have to pull in people who generally really don't have time
to care about why one user logs on and doesn't get the proper policy. Pushing
the policy setting to the local machines allows the local admin to have
considerably more direct control over the user's experience on the given machine.

The times that I feel that Domain based policy is useful is for things like
corporate password policies or managing some basic settings on thousands of
workstations (but with a few fixed policies, no ad hoc crap) or possibly if you
have a group of server machines that you can not trust the admins for and even
then, if they are bright enough, they are going to counter anything you do with
the policy anyway. The system isn't that bulletproof and quite honestly Windows
was never designed to be bulletproof from the local admins or anyone who can
become a local admin (i.e. anyone with physical access). If you have a problem
with local admins, the issue is a policy issue alright. Just not a technical one
and you can not solve it with technical solutions including domain group policy.

Things like software delivery etc all have other better mechanisms for handling
and stacking all of this crap into a process that can impact user authentication
is a generally overall all around bad idea. That goes double for
complicated/complex logon scripts. I see these in the same light that I see
GPOs, people see a mechanism that looks like it will work and whether it is a
good idea or not jump right into using it and then wonder why things are shitty
later.

My overall goal when looking at Domains and Domain Controllers is to make the
environment as simple as possible. Far less items break that way and when they
do it is MUCH easier to troubleshoot meaning that people can focus on proactive
intelligent work versus troubleshooting and firefighting all of the time. The
company that I mentioned has probably the best running AD I have yet to
encounter in 6 years of working on AD and 2 years of consulting with one of the
larger technical service organizations on AD/Exchange issues. Their admins (4 of
them now because they picked up ADAM support as well as AD) manage some 400 DCs
across the world comprised of ~250k users and at least that many machines (and
an ADAM pool that will end up servicing probably a million or so users) out of
one site in the US and rarely have a pager go off because something is broken or
not working. I have lunch with them every couple of months and they are free to
comfortably and relaxingly take 2-3 hour lunches. They get to spend good time
looking at upcoming changes such as Schema updates, etc and make sure they are
good versus not having any real time to look at anything and just having to
trust that the people bringing it to them can be trusted. This wasn't always the
case, when I first joined them back initially in 1999 and returned in 2001 it
was a nightmare, pager going off at all hours, people screaming and hollaring
about this that and the other thing being broken, etc. It slowly got better as
the environment was simplified and locked down from people making modifications.
At this point there is a provisioning system that handles all userid updates
except to the 4 (5 if you include the manager who isn't allowed to change
anything but has a just in case DA ID) Domain/Enterprise Admins, all server
account creations are handled by the DAs, all group/OU creations are handled by
the DAs, workstations creations are handled by the workstation build process
though local site admins can manually create them if necessary though automated
scripts I wrote called jail scripts verify that they are done correctly and
actually are workstations instead of servers. If someone tries to do something
they aren't supposed to the object is jailed meaning that only DAs can do
anything with the object and the machine is dead in the water. Local site admins
are responsible for and can directly manage group membership but it is likely
they will even lose that direct capability and that will go into provisioning
because it is generally being handled poorly because they aren't auditing and
cleaning up membership as they should. Again, this is the best running most
efficient, least troublesome AD I have ever seen. Most DAs I meet are harried
and constantly fighting fires and chasing issues and barely have time for a 15
minute con call or to look at any proactive items like perf counters, etc.

MS does a lot of stuff with their OS, not all of it good for companies and just
because it works for very small numbers when some integrator is testing it
doesn't mean it should be deployed and used corporate wide. Can GPOs be used
effectively and well and not cause issues, yes, but in my experience that has
been in the minority of places I have spoken with people and usually only if the
whole thing is well tested in a lab and then rolled to production very carefully
and completely locked down from ad hoc updates at all points. Any time I walk
into a company and there are a large number of GPOs and/or non-DAs have the
ability to modify/create GPOs there is almost always some level of issues there
that people can't nail down.

As for best practices, they vary by company. Different companies do things in
different ways and see different issues. I take the best practices advocated by
MS with as much a grain a salt as those by any company until I have personally
proven out their benefit to myself in a given situation or several situations.
For instance the MS docs for building a domain controller talks about using
RAID-1 and doesn't really outline when that idea absolutely sucks and for the
most part in larger orgs using RAID-1 absolutely sucks because the disks can't
handle the Read Ops that are necessary but the docs from MS don't say anything
about that. If you talked to Dev or the folks in Enterprise Engineering they
will have completely different opinions than what MS officially documents for
many things.

I have one word I use to describe Microsoft (or anyone's for that matter)
documentation that I haven't personally vouched for and approved, propaganda.
Anyone who has taken any MOC course and then really worked in an environment
generally feels quiet similar. Even if you haven't taken a MOC course there is
enough docs out there that after you read them and visit the real world you see
they don't exactly align.

So anyway, if someone implements GPOs and everything works great for them and
they have a good handle on it that is great. I would however, not force anyone
to do it because Microsoft says it is the best practice for doing it. When I
walk into an environment I look to see how I can help the DAs, not force them to
take on more work and concern. You want DAs as friends, not as enemies. Discuss
with them what you would like and listen to what they respond with. No's that
are sent back will either be well thought out or they will be gut responses. If
well thought out, if they are willing to tell you why listen and see if you can
quell concerns. No's that are gut feelings also try to work out but understand
that they may not have a good clear reasoning YET. I have learned to trust my
gut because it often knows there is a problem before I do logically, gut
feelings is simply subconscious thinking or worries coming up and is worth
listening to but you should try to substantiate the gut with well thought out
logical thoughts as soon as possible. Obviously the registry corruption response
was silly. It could be you have a really bad admin on your hands, however, being
a bad admin doesn't mean everything they think of or do is wrong, they could
just be very poor at explaining what the problem is or what they think and grasp
onto anything they think will make someone go away. On the other hand it could
be a good admin that has a feeling you don't know what you are talking about and
is willing to just say things that he thinks will make you go away. DAs are the
target of lots of people in the company all who think they know better than the
DA what needs to be done. I used to hit this daily and unfortunately for most of
those people, many of whom were developers or integrators I usually knew far
more about the Domain and environment than they did and often more about what
they were trying to do than they did. Not all of them got better answers from me
than simply, no, that isn't going to happen. On the other hand in some cases I
would write whole programs to show them the error in their ways, it was my
judgment as the DA how much time I would spend on their problems.

Oh one thing that stuck out below also was the comment of something like "we are
talking about one OU and one GPO". As a former DA, that is how it always starts
out and then it starts growing. DAs have been trained to realize that the people
coming to ask them for things are probably lying or don't have a clue and they
need to try and figure out what will happen 2 months, 6 months, 2 years down the
road. Someone comes to me with a request for a single OU and single GPO and I
know that at some point, it will be a case of ok, we did that once, now we need
to do it again BUT this time... Even worse is the idea that it is a one off. One
offs are costly and people forget them. Why does anything built by hand cost
more than the same thing built on an assembly line? Labor. It is more intensive
to do things onesy-twosy than to produce a generic process. If you want to make
a change to an OU, make that the standard for all OUs. The company I did the
work for couldn't have been anywhere near as efficient for the AD stuff if there
wasn't a completed fixed OU structure for every site. You need a new site spun
up, one single script created all 10 or so OUs required for it and built all of
the new groups and set all of the delegated permissions. Total time, maybe 3-5
seconds. Total mistakes, 0. Doing that all by hand takes minutes at least and no
guarantee of accuracy or consistency.


joe


--
Joe Richards Microsoft MVP Windows Server Directory Services
Author of O'Reilly Active Directory Third Edition
www.joeware.net


---O'Reilly Active Directory Third Edition now available---

http://www.joeware.net/win/ad3e.htm
 
Now I know what it feels like to be a ant getting run over by an 18 wheeler.
[LOL] Seriously, I'm amazed by the high level of expertise encountered in
these newsgroups.



But Joe, is it accurate to lump enterprise Terminal Services policy in with
"special little needs of every little occasion"? I agree that Microsoft best
practice recommendations may not always apply in the real world, but the
real world assessment works both ways. I doubt if most IT shops can afford
to model their practices after an enormous organization with expensive
add-on tools, consultants and 4 or 5 dedicated domain admins who have time
for relaxing 3-hour lunches in part because they say "no" to everything that
might result in more work in their part.



Maybe we should start another post on how dumb I am for trying to win
debating points against someone vastly more experienced--especially given
that we have long lines of indigent patients backing up due to slow
application response time. Our pharmacies are begging for TS to be
implemented (I demonstrated how much faster it is during testing).



I'm ready to do whatever will get those patients their medicine without
unnecessarily endangering our network. I got caught up in defending the
domain policy approach partly because I've spent just about all the time I
can afford researching that approach. I don't know which way to go anymore.



Can you or anyone help with a few small details concerning the local policy
approach? I've used gpedit.mcs to create local machine policy. Is this the
correct tool for creating the TS lockdown policies? (I installed the new
Group Policy Management Console, but I don't see any obvious way to use this
for creating local machine policy.) We should use computer-level policy or
user-level or both? Exactly how would you save and copy this policy template
to another machine?



Because no one else in our department has time, I've been reading about
terminal services, group policy and AD at night over the last two weeks. I
have a strong IT background, but little hands on experience with these
specific technologies. Someone posted a knowledge base reference for
creating a local "deny apply" rule to allow remote admin access to the
Terminal Server, so I'll be reading that tonight.



Thanks to everyone for helping.
 
mg said:
Herb, I agree in general we need to educate when possible. This will be an
extremely slow and difficult process in this case because we have someone
who
believes they are more expert than anyone else including Microsoft when in
fact they lack experience and knowledge in this area. I've already had to
overcome completely bogus objections to the standard/best practices
approach
to this issue--objections such as an OU/linked GPO solution will hurt
network
performance and making any changes to Active Directory might corrupt it
(Maybe we should just shut all the computers off to completely avoid
this!),
etc.

But that last objection will at least open the for the CIO to ask if he is
backing up the domain controller(s) adequately which I doubt.

There is a point where you have to either go to management,
learn to live with it, or start finding a new job.

If management doesn't supervise such loose (and wobbly)
cannons then the firm is not really in very good shape and
looking for a new job may be the best bet.
 
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