Administrator Guide

NOTE: Dell does not recommend using a combination of local and external authentication where replication and quotas
are applied.
External Authentication
External authentication is managed on a server whenever a user logs in to a container in the same group as the server. Using
external authentication, a user can log in to dierent containers in the group using the same user name and password. This
authentication is performed with Active Directory, LDAP, or NIS, for example.
When a user logs in to a container using external authentication, the user and group quotas dened for that user and any groups that
the user belongs to are applied to that user while logged in to that container.
Local Authentication
Local authentication is managed directly on a container. With local authentication, the user name and password that a user enters to
log in to a container apply only to that container.
When a user logs in to a container using local authentication, the user and group quotas dened for that user and any groups that
user belongs to are not applied to that user. The quotas for the local user and the primary group for that local user are applied to that
user, with the user quota taking precedence over the group quota.
About NAS Thin Provisioning
Thin provisioning enables you to eciently allocate storage space, while still meeting application and user storage needs. With a thin-
provisioned NAS container, space is created based on actual container data usage, enabling you to “over-provision” NAS cluster
storage space (provision more space than what is physically available).
When NAS containers are thin-provisioned, NAS cluster storage space is consumed only when data is physically written to the NAS
container, not when the NAS container is initially allocated. When data is written to a container, it initially lls or consumes reserved
space. When reserved space is exhausted, it begins to consume unreserved space.
Thin provisioning oers the exibility to provision NAS clusters to account for future increases in usage. However, because it is
possible for the storage space used by the NAS container to exceed the storage space allocated to the NAS reserve, you should
monitor available capacity to ensure that the NAS reserve always has sucient free space available.
You can also specify a portion of the NAS container (reserved space) that is dedicated to the NAS container (no other container can
take the space). The total reserved space of all NAS containers cannot exceed the available capacity of the NAS reserve. If a le is
deleted from an unreserved portion of a thin-provisioned NAS container, the free space as seen in the NAS cluster increases. The
freed-up capacity is also visible and available to clients in the SMB shares or NFS exports.
NAS Container Storage Space Terminology
The following list denes terminology used in Group Manager related to NAS container storage space.
Term
Description
Size Maximum size of NAS container dened by the storage administrator.
Used Space Storage space occupied by writes to the NAS container (user data and snapshots).
Reserved Space A portion of a thin-provisioned NAS container that is dedicated to the NAS container (no other container
can take the space). The amount of reserved space is specied by the storage administrator. Reserved
space is used before unreserved space.
Unreserved Space A portion of a thin-provisioned NAS container that is not reserved (other containers can take the space).
The amount of unreserved space for a NAS container is the NAS container size minus the reserved space in
the NAS container.
NAS Container Operations
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