RE: Metaphysical question about DFS



It's been quite some time since I played w/DFS, but from what I've found, it
appears that you are correct regarding the site designation - that is,
clients will select any available DFS server in the site, and since all of
your locations will be in a single site, there doesn't appear to be any way
to link to a subnet instead of a site. The following is from "How DFS Works":
http://technet2.microsoft.com/WindowsServer/en/library/a9096e88-1634-4da6-b820-537341d349061033.mspx?mfr=true

How Target Selection Works
When a client computer attempts to access a root or link in the namespace, a
domain controller or root server provides a referral to the client. The
referral contains a list of target servers, and this list is sorted according
to the currently configured target selection method.

Default Target Selection
By default, DFS places target servers in the referral in the following order:

1. Targets in the same site as the client are listed in random order at the
top of the referral.
2. Targets outside of the client’s site are listed in random order.

The question I would ask is what benefit will your organization gain by
placing all of your locations into a single AD site? What justification did
the consultant give for making this change to your infrastructure?

Steve

"ThOF" wrote:

Hi all the group;

I've a a little "complex" question about DFS working in Windows 2003 and I'd
need your help and comments about it

At present, in my enterprise, we work with a network topology divided in
five sites, everyone of them with its own GC/DC (one site can be one main
office or branch-office)

A consultant firm has come to take a look to our present situation and they
have proposed to merge all the sites in only one new site, due to the fact
that our WAN links are very fast (10 -100 Mpbs). So, by performing that
change, we would have all the GC/DCs logically located in the same site (of
course, the physical location won't change).

In fact, I've to confirm that our WAN links are quite good (fast and
reliable) as we work with MPLS technologie and fiber optic from end to end

The thing is, we have already implemented DFS some months ago, so access to
shared resources is transparent to the users, no matter their physical
location (the user will always access to, for example,
\\mycorporation.com\Data no matter they are working today in Madrid or
tomorrow in Barcelona, because the XP clients will always connect to a local
DFS server -target server- located in the same site as the user is.

This is to say that every main office/branch-office will keep having its own
subnet in 'Active Directory & Services', so this is not going to change (for
example, Barcelona offices will keep its 192.168.1.0/24 subnet range, Madrid
will continue having 192.168.2.0/24, and so on)

What we're afraid is that, when we merge all the sites into the new one, all
the network subnets will belong, of course, to the same site
(192.168.1.0/24, 192.168.2.0/24, ...); in other words, all the network
subnets will be preserved and they will belong to the new 'MyEnterprise'
site but... what about DFS behaviour from that moment on?

I've readed that, when working with DFS, the DFS client -this is, the
Windows XP PC- when starting the network session and logging into the
domain, it will always look first for a target DFS server located in the
same site as the user is (based in the pair IP-subnet) but nowhere in the
FAQs nor white papers it is specified anything about looking first one
target server in the same SUBNET, too (I mean, this is not clear if the DFS
client only looks first for a target server in the same site OR also in the
same subnet)

For example, if the client PC has an 192.168.1.25 IP address, then I'm not
very sure about the DFS client looking first for a target server also
located in the 192.168.1.0/24 subnet or, on the contrary, it will only
search for any alive DFS server no matter the client IP matches or not)

If the last happens, it could occur that, for example, an user located in
Madrid would sometimes/always connect against a DFS server in Barcelona, or
vice versa

We're a little worried about this possible issue, because we don't want
that, when merging sites, the user DFS experience gets worse (OK, our WAN
lines can be fast enough, but you will have to agree with me that there is
no point in the users connecting to a "remote" server when there is another
one located locally and where they can connect to with a speed of 1 Gpbs, so
is not the desired situacion)

I've also readed that starting with Windows 2K3 SP1, new DFS features and
improvements have been added (for example, more available options when using
the 'dfsutil' tool). Now it is possible to define some kind of "priority",
so we can define an ordered list with the preferred DFS servers in one site
(high, low or normal priority) but I'm afraid this new stuff wouldn't solve
our problem, because as all the servers will be located in the same site,
defining priorities won't help (if I define the Barcelona server as the one
with the highest priority, then I guess it is for sure that all the rest of
clients located in remote offices will always connect to Barcelona, which is
not desired)

Well, I don't know if I explained myself in a clear way. I hope so.

Any feedback or comments about the subject will be highly appreciated.

Regards and many thanks in advance.



.



Relevant Pages

  • RE: Connect share in VPN
    ... By the way I can browse individually share that form my DFS. ... 5- There is nothing in the event log about remote access. ... > clients cannot access the DFS shares on the SBS Server remotely via VPN ... > problematic remote client was directly connected to the internet. ...
    (microsoft.public.windows.server.sbs)
  • RE: Distributed File System questions
    ... The Windows DFS is the network file system for the environment. ... Dfs is composed of server and client components. ...
    (microsoft.public.windows.server.sbs)
  • RE: DFS
    ... dfs, my problem is my xp-pro sp2 client can't failback to my second server ... when the 1st server is down. ... the DFS namespace client failback feature has some ...
    (microsoft.public.windows.server.sbs)
  • Re: ABE in a DFS Environment
    ... Yes, right click the root in the DFS management, and then add new link. ... > I understand that you installed ABE on both SBS 2K3 Server and Windows ... did you access the shared folder by ... > root target you created and select New Link? ...
    (microsoft.public.windows.server.sbs)
  • Re: How does DFS pick a Server?
    ... if you are wondering why these small offices have a file server but ... > a Domain Controller it is because or company has a policy that DCs cannot ... >> target selection is enabled, a client computer might access a target ...
    (microsoft.public.windows.file_system)