This article describes the basic procedure for sharing home
folders on a shared disk on a cluster.
In Cluster Administrator, it is not the optimal
configuration to create a cluster file share resource for every user's home
folder. Not only does this require a lot of administrative work, but it also
uses memory and CPU resources that it does not need to. The Cluster service
uses memory and CPU cycles for every resource you have defined in Cluster
Administrator. The more resources you have, the more overhead that the Cluster
service generates. Assuming that there are 750 users' home folders on a
cluster, a file share resource would be created for every user. Failover times
from one node to another increase, as well as viewing resources in Cluster
Administrator. The worst-case scenario is that a very busy cluster may drop
connections because of the amount of time being used to manage 750 cluster
The optimal way to use a server cluster to house home
folders is to use the "Share sub-directories" or dynamic shares feature. The
basic principal behind dynamic file shares is that a single cluster file share
resource is created, yet an independent file share is created for every user
folder. For example:
Drive Z is the shared disk. The Z:\Users folder is the root share
that contains all user home folders.
- Create a cluster file share resource for each user. In this
case, a cluster resource is defined five times for each user under the Z:\Users
- Set NTFS Permissions on the
Z:\Users\Username folder to allow only the intended
user access the folder.
- Every time a user is created, go to the Z:\Users folder and
create the proper folder with permissions. Then use Cluster Administrator to
create a file share resource.
- Create a single cluster file share resource to the Z:\Users
- Give the Everyone group Full Control share-level
permissions in Cluster Administrator.
- Using the Parameters tab for the root cluster file share resource, click to select the
Share all sub-directories check box.
- Set NTFS permissions on the
Z:\Users\Username folder to allow the intended user
to access the folder. The Cluster Service account needs to have at least Read
permissions. At this point, all folders under Z:\users are automatically shared
with the same network permissions as the root share. To add a user when you are
using dynamic shares, create a folder under Z:\Users and assign proper NTFS
permissions (see step 4). The Cluster service automatically shares the
NOTE: When you perform the following step, you do not hide the
directories under a share, only the shares themselves.
- To make the user shares hidden, use the Parameters Tab for
the root cluster file share resource, and then click to select the Hide subdirectory shares check box. This action appends "$" to the end of the shares
located under Z:\Users\<Username>.
The "Share sub-directories" feature was added to the Microsoft
Windows NT 4.0, Enterprise Edition, Cluster service with Service Pack 4, and
enhanced with Service Pack 5. Apply Service Pack 5 if you plan to implement
dynamic file shares. Windows 2000 Advanced Server includes this feature.
If the sub-directories are shared in a Clustered file share, and
there are more than one file share groups within the cluster that use
environment variables by username, the following behavior may occur when the
groups are brought online on the same physical node.
For example, you have drives
in each group that
the following folders:
- \\<virtual_server1>\users Drive U: |-- users |--
user1 |-- user2
- \\<virtual_server2>\data Drive Z: |-- data |-- user1
you use environment variables and either
or both of the following
two virtual server groups come online on the same
physical node, users
can connect to the correct shares:
if you use the
either or both of the following virtual server groups, users may experience
inconsistent results when they map network drives:
- "net use * \\<virtual_server1>\%username%"
- "net use * \\<virtual_server2>\%username%"
Lanman server Service does not differentiate between
shares. Therefore, it cannot distinguish that
different file shares. When the second instance of the %username% file
share tries to share, the
following error 2118 occurs in the Cluster log file,
and that share will not be
WARN File Share <Data>: SmbpCheckAndBringSubSharesOnline:
NetShareAdd failed for subshare <user1>$ Error: 2118.
Share <Data>: SmbpCheckAndBringSubSharesOnline: NetShareAdd failed for
subshare <user2>$ Error: 2118.
C:\err>err 2118 # for decimal 2118
/ hex 0x846 NERR_DuplicateShare lmerr.h # /* The name has already been shared.
Because the second shares do not exist, the drive
to the first share. The best solution to avoid share name collision is not to
share sub directories under the advanced properties of the File Share resource
in Cluster Administrator. You can use ABE (Access-based Enumeration) to apply
ACLs (Access Control List) for the user subdirectories. For more information, click the following article
number to view the article in the Microsoft Knowledge Base:
How to implement Windows Server 2003 Access-based Enumeration in a DFS environment
Alternatively, the file shares can be created by
using one of the following two methods:
- Rename all subfolders under the original share locations to
something different so that they will never match
- Do not share sub-directories, and map everything to
\\<virtual_server1>\users or to \\<virtual_server2>\data or to both.
Then, use NTFS permissions so that the users can only access their own share.
Securing a common folder
SP4 Cluster shares must be reset to recognize added subdirectories
How to create file shares on a cluster
Security considerations when implementing clustered file shares
Microsoft Cluster Server may not share folders automatically
Article ID: 256926 - Last Review: October 26, 2007 - Revision: 3.2
- Microsoft Windows Server 2003, Enterprise Edition (32-bit x86)
- Microsoft Windows 2000 Advanced Server
- Microsoft Windows NT Server 4.0 Enterprise Edition
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