Calsoft Blog

The recent changes in the storage industry may be signaling the end of the SAN era. Why? The problem that SAN was designed to solve, still exists, which was to replace locally attached storage. The advent of Gigabit and Gigabit 10 in late 2010 removed the need for FC SAN. NAS, which was the prominent tool before SAN, had to be removed due to their archaic file system protocols that could not keep up with the demands of the developing technology that were eventually solved by advanced Linux technologies and specialized file systems designed to run on them, such as the LFS, ZFS, JFS, DFS, NTFS, JFFS, HPFS, HDFS, etc. These required users to move to SAN to get access to centralized RAW volumes that can be mounted on the mission-critical application servers to make use of the newer file system. Things changed for SAN manufacturers as the Hard Disk density kept increasing and the cost of manufacturing kept falling. Today, disks made for desktops are >2TB with comparab...

Software defined storage is the latest buzz in the storage industry. It gives rise to questions such as how software-defined storage is different from storage virtualization? Is this just old wine in a new bottle? Let us evaluate. Since the storage was developed it has continued to evolve and being deployed as an external device. JBOD was a simplistic external storage in the early days. However, it came with a couple of disadvantages: disk sizes were fixed and there was no protection against disk failures. RAID, the disk failure protection system, was born. However, RAID did not solve the problem computer systems themselves being susceptible to failures. This made RAID software be placed inside HBA adaptors, and then placed inside JBODs making them more robust, failure tolerant and resistant. This allowed more advanced features such as replication, snapshot, and deduplication. Though modern hardware storage arrays have many advance features, they are applicable onl...