Tips to tier storage without system-controlled storage tiering

Everyone is dealing with a constant battery of increasing storage requirements. How do we ensure that storage performs optimally absent of technologies to automate performance? IT pro Rick Vanover shares some tips on manual storage provisioning.

I don’t think that I am in alone in dealing with ways to make storage systems perform better. Further, I’m the type that usually doesn’t delete anything from disk. Whether the storage system is a home user, small business or large organization; many of the challenges are similar.

The issue becomes when storage systems get full or otherwise start to under perform. One way to approach this challenge is to have a system controlled storage tiering solution, such as Hitachi Dynamic Tiering or EMC’s FAST. These solutions will move data, at the LUN or sub-LUN level from one tier of storage to another based on policy. While these are great technologies, what do you do if these options aren’t available? Here are some tips to tier storage with minimal cost:

Revisit direct attached storage:

Many servers have very capable direct attached storage (DAS) with large drives and fast storage controllers. Further, these storage controllers may not be highly utilized. If a number of servers are full of lesser-critical data such as CD-ROM .ISO files or backups of backups of backups from another system, a series of file servers on DAS may be appropriate. Further, if one or more servers have underutilized local storage; consolidating any available disks to another server may be an option.


This is the hard one. What really needs to be retained? A data retention policy would be a good resource to have to cover all of the bases, but many times the requirements for such are not firm and in place. This is a challenge for me as well in my home lab, meaning if I have room for it; I should keep it. This may be a good time to start to create a retention policy.

Disk offload:

For a tier of storage that is retention-only or if an answer can’t be determined if this data is to be retained, having offline hard drives or tape to hold the data can be an option. If standalone drives are used; consider making duplicate, triplicate, or more copies and storing in different locations.

Cloud offload:

Can’t seem to avoid this one today it seems. There are a number of ways to offload content to the cloud, including some ready-to-go solutions such as Nasuni or Cirtas. In my earlier post on using a cloud file resource as an alternative to the traditional file server, I suggested that this can relieve local content requirements on site.

Under-utilized SATA storage:

Generally speaking, there are two types of rotational storage in use for servers today: SATA and SAS. Solid state disks and enterprise flash are available for servers today, but if you have money for these; you wouldn’t be reading this tip. A good rule of thumb on comparing SATA and SAS storage is that SATA is three times the capacity, 1/3 the price and 1/3 the performance of SAS drives. The reverse can be said for SAS drives that they are three times the performance, 3 times the price and 1/3 the storage of the same dollar spent on SATA drives. Of course there are more factors involved, but if you have ample SATA storage, it may be worth considering putting an application or virtual machine on a SATA resource that is under-utilized. This would take contention off of a higher tier of storage yet give it the next-best location in a SATA storage resource that doesn’t have contention.

Smaller SAN sprawl:

I can go either way here, but one strategy is to implement a stopgap solution of smaller storage devices to offload from primary resources. There is one thing I’ve learned over the years, you can always find less expensive storage. A smaller, lesser performing and lesser cost device may be rolled in to offload storage and performance consumption on the primary storage resources. This could be only for a temporary capacity, depending on the situation.

The overall objective is to better help the organization to meet its goals. Having data available, protected and performing correctly is critical to this strategy.

What tricks have you employed to get more out of the storage you have with minimal costs? Share your comments below.