Hardware Reference
In-Depth Information
FIGURE 11.3: Single file system starting at the root inode
/ifs
.
partitioning, and no need for volume creation. Instead of limiting access to free
space and to non-authorized files at the physical volume level, OneFS provides
for the same functionality in software via share and file permissions, and via
the SmartQuotas service, which provides directory-level quota management.
Because all information is shared among nodes across the internal network,
data can be written to or read from any node, thus optimizing performance
when multiple users are concurrently reading and writing to the same set of
data.
Figure 11.3 illustrates that OneFS is truly a single file system with one
namespace. Data and metadata are striped across the nodes for redundancy
and availability. The storage has been completely virtualized for the users and
administrator. The file tree can grow organically without requiring planning
or oversight about how the tree grows or how users use it. No special thought
has to be applied by the administrator about tiering files to the appropriate
disk, because SmartPools will handle that automatically without disrupting
the single tree. No special consideration needs to be given to how one might
replicate such a large tree, because the SyncIQ service automatically paral-
lelizes the transfer of the file tree to one or more alternate clusters, without
regard to the shape or depth of the file tree.
This design should be compared with namespace aggregation, which is a
commonly used technology to make traditional NAS \appear" to have a single
