1. Use Storage Management
Storage Management software is available in a wide variety of price ranges, from free open source packages, to expensive enterprise-class systems that continuously monitor storage and optimize usage. Of course, you can also simply search your drives manually for large files, MP3s, JPEGs, or PST files. The general idea is to identify possible files that aren’t needed or could be stored on other storage, like local PC hard disks, which often have lots of unused space.
It isn’t necessary to spend a lot here; for instance, you can send an email asking all users to archive unused email files to a PST on a local drive. Be sure to include directions, and it will greatly reduce the storage used by the your email server. Likewise, you can implement policies on storage of personal files to ensure that they’re not taking up space on the company network.
2. Use Deduplication or Compression
Once you’ve pruned existing files, you can use deduplication or compression to fit more data into your storage. Deduplication scans a storage system, looking for duplicate files, and deletes the extra copies of the files, leaving a placeholder where they were. Any user who tries to access the placeholder gets taken to the proper file. Compression, which reduces the amount of space used by files, works best on files such as word processing or other text files, and is less effective on media files, since they're often already compressed.
3. Create Storage from Unused Space
Once the systems are up and running, you can use them for any type of files, though you may want to use them as secondary storage, keeping the newer, higher performance storage for the most important applications, such as email, databases, collaboration or home directories.
4. Move Files to Secondary Storage
Many organizations have high-performance storage such as fibre channel or iSCSI RAID systems for important applications, but often that same storage ends up being used for applications that don’t need the high speed. You can use storage management applications, or move data manually, but moving less frequently-needed data to secondary storage can free up lots of space on the expensive equipment. Storage management software often can allow you to create several tiers of storage, including one with the highest performance a less-expensive high-performance system, a secondary storage system, as well as offline storage such as tape or optical disk.
5. Consider the Cloud
Whether it’s to ride out the results of flooding, or to deal with the ever-increasing amounts of data in use in most organizations, there are alternatives to just buying more storage. Many newer storage systems from vendors such as EMC, NetApp, HP, or Compellent offer the features mentioned above, including storage management, compression or deduplication, storage tiering and storage migration. But you can get some of the same results without buying a new system, using readily available software or doing the tasks manually.