Having gleaned the necessary information about your customers’ current and
projected storage needs, the next step is to map groups and subgroups onto
the storage infrastructure. At this point, you may have to decide whether to
group customers with similar needs by their application usage or by their
reporting structure and work group.
If at all possible, arrange customers by department or group rather than
by usage. Most storage-resource difficulties are political and/or financial.
Restricting customers of a particular server or storage volume to one work
group provides a natural path of escalation entirely within that work group
for any disagreements about resource usage. Use group-write permissions to
enforce the prohibition against nongroup members using that storage.
Some customers scattered across multiple departments or work groups
may have similar but unusual requirements. In that case, a shared storage
solution matching those requirements may be necessary. That storage server
should be partitioned to isolate each work group on its own volume. This
removes at least one element of possible resource contention. The need for
the systems staff to become involved in mediating storage-space contention
is also removed, as each group can self-manage its allocated volume.
If your environment supports quotas and your customers are not resistant
to using them, individual quotas within a group can be set up on that group’s
storage areas. When trying to retrofit this type of storage arrangement on an
existing set of storage systems, it may be helpful to temporarily impose group
quotas while rearranging storage allocations.
Many people will resist the use of quotas, and with good reason. Quotas
can hamper productivity at critical times. An engineer who is trying to build
or test part of a new product but runs into the quota limit either has to spend
time trying to find or free up enough space or has to get in touch with an SA
and argue for a quota increase. If the engineer is near a deadline, this time
loss could result in the whole product schedule slipping. If your customers
are resistant to quotas, listen to their rationale, and see whether there is a
common ground that you can both feel comfortable with, such as emergency
increase requests with a guaranteed turnaround time. Although you need to
understand each individual’s needs, you also need to look at the big picture.
Implementing quotas on a server in a way that prevents another person from
doing her job is not a good idea.