March 2013
Dell EqualLogic Configuration Guide v14.1
12-116
accessible as CIFs shares and NFS exports, a general rule of thumb for how to assign the security style
would be as follows:
•
If your users are predominantly Linux/UNIX based, use the UNIX style.
•
Likewise, if your users are predominantly Windows/CIFS based, use the NTFS style.
•
If you have mixed clients, use the style applicable to majority of users. Then create a user mapping
of your Windows to Linux users or vice versa. The user permissions are equivalent to the mapped
user. Note that the Mixed Mode container security style should not be used for cases where you
have a mix of both CIFS and NFS clients.
12.4
NAS Container snapshots
Dell FluidFS snapshots are created and managed by the FS Series appliance to provide a container level
snapshot capability. They are read-only and are created using a redirect-on-write method. This
method is also referred to as allocate-on-write. This approach requires only one I/O operation and
delivers higher write performance.
Note:
FS Series FluidFS snapshots and PS Series volume based snapshots function
independently and have no impact on each other.
Please see the following whitepaper for more information on Dell FluidFS snapshot
behavior:
Dell Fluid File System:
http://www.dellstorage.com/WorkArea/DownloadAsset.aspx?id=1578
Additional FluidFS snapshot limits and considerations:
•
Each NAS Container has its own snapshot policy.
•
The minimum unit a snapshot can act on is a NAS Container.
•
The maximum number of snapshots you can retain per container is 512. The maximum
snapshots retained per FS appliance cluster is 10,000.
•
When you create a snapshot, all shares and exports within that container are included. If a
particular share or export will require frequent snapshots, you should group it with others that
have the same requirement, or dedicate a container to that particular share or export.
•
The FluidFS snapshot implementation allows for end users to individually select and restore
previous versions of files. The .snapshot directory contains all the snapshots taken for the
container. Browse to the correct snapshot directory to access the files needed to be restored
to the share. Windows users can also use the “Previous Version” feature of Windows files and
directories to restore individual files or entire folders.
Sizing limits and space utilization considerations for FluidFS snapshots:
•
The size of the snapshot reserve is specified as a percent of the container size. It is set at
container creation and changes according to the % reserve setting whenever the size of the
container is changed.
•
The default snapshot reserve size is 50%. It is common to select a reserve size in the range of
25%. The maximum snapshot reserve size is 90% of the FS size.
•
The snapshot reserve capacity is counted against the NAS container reserve space. However,
the snapshot reserve space is not enforced. Container data can fill the snapshot reserve space.
Содержание EqualLogic PS4100E
Страница 18: ...March 2013 Dell EqualLogic Configuration Guide v14 1 1 9 Figure 2 Fully connected controller failover ...
Страница 54: ...March 2013 Dell EqualLogic Configuration Guide v14 1 6 45 Figure 13 Replication Process ...
Страница 86: ...March 2013 Dell EqualLogic Configuration Guide v14 1 7 77 Figure 27 Minimum cabling scenario PS6100 ...
Страница 133: ...March 2013 Dell EqualLogic Configuration Guide v14 1 13 124 Figure 44FS7610 network ...