HP ProLiant DL380 G5 DPSS, Administration Manual

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As previously mentioned, the fi le-sharing security model of the storage server is based on the NTFS
fi le-level security model. Share security seamlessly integrates with fi le security. In addition to discussing
share management, this section discusses share security.
Share considerations
Planning the content, size, and distribution of shares on the storage server can improve performance,
manageability, and ease of use.
The content of shares should be carefully chosen to avoid two common pitfalls: either having too many
shares of a very speci fi c nature, or of having very few shares of a generic nature. For example, shares for
general use are easier to set up in the beginning, but can cause problems later. Frequently, a better
approach is to create separate shares with a speci fi c purpose or group of users in mind. However,
creating too many shares also has its drawbacks. For example, if it is suf fi cient to create a single share
for user home directories, create a “homes” share rather than creating separate shares for each user.
By keeping the number of shares and other resources low, the performance of the storage server is
optimized. For example, instead of sharing out each individual user’s home directory as its own share,
share out the top-level directory and let the users map personal drives to their own subdirectory.
De fi ning Access Control Lists
The Access Control List (ACL) contains the information that dictates which users and groups have access
to a share, as well as the type of access that is permitted. Each share on an NTFS fi le system has one
ACL with multiple associated user permissions. For example, an ACL can de fi ne that User1 has read
and write access to a share, User2 has read only access, and User3 has no access to the share. The
ACL also includes group access information that applies to every user in a con fi gured group. ACLs are
also referred to as permissions.
Integrating local fi le system security into Windows domain environments
ACLs include properties speci fi c to users and groups from a particular workgroup server or domain
environment. In a multidomain environment, user and group permissions from several domains can apply
to fi les stored on the same device. Users and groups local to the storage server can be given access
permissions to shares managed by the device. The domain name of the storage server supplies the
context in which the user or group is understood. Permission con fi guration depends on the network and
domain infrastructure where the server resides.
File-sharing protocols (except NFS) supply a user and group context for all connections over the network.
(NFS supplies a machine-based context.) When new fi les are created by those users or machines, the
appropriate ACLs are applied.
Con
fi guration tools provide the ability to share permissions out to clients. These shared permissions are
propagated into a fi le system ACL, and when new fi les are created over the network, the user creating the
fi le becomes the fi le owner. In cases where a speci fi c subdirectory of a share has different permissions
from the share itself, the NTFS permissions on the subdirectory apply instead. This method results in a
hierarchical security model where the network protocol permissions and the fi le permissions work together
to provide appropriate security for shares on the device.
NOTE:
Share permissions and fi le-level permissions are implemented separately. It is possible for fi les on a
fi le system to have different permissions from those applied to a share. When this situation occurs, the
fi le-level permissions override the share permissions.
Comparing administrative (hidden) and standard shares
CIFS supports both administrative shares and standard shares.
• Administrative shares are shares with a last character of $. Administrative shares are not included
in the list of shares when a client browses for available shares on a CIFS server.
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File server management