Rather than directly start with Fibre channel, SAN storage, SSD drives, FcOE and their Do’s and Don’ts, we should know some background and History of Storage to know it in a better way….. What do u say Guys 🙂
So let’s learn Storage from Basics. I am preparing this document in very simple format just to make it clear for you all.
Prior to Hard Disks there was Volatile Data Storage which is nothing but a RAM, fastest access of the data because there are no moving parts 🙂 To store the data permanently the earliest form of storage was the magnetic tape used by mainframe computers. Later form of removable permanent data storage was the Floppy Disks.
The program and application grew larger in size, the need arose for larger internal forms of permanent storage. Then, IBM PC/XT came with an MFM (Modified Frequency Modulation) interface. This was all used in late 1980s and early 1990s. The later type required to install special software that provided a BIOS extension for expanding the Logical Block Addressing (LBA) and persistent storage drives Enhanced Small Disk Interface (ESDI). Along with it SCSI launched which is a Small Computer System Interface, the most successful and reliable interface. It grew larger and faster, the interface also evolved from parallel to serially attached SCSI (SAS).
Then, IBM introduced PC/AT computers first with IDE Diskswhich were actually AT Attachments i.e ATA and AT Attachment Packet Interface i.e ATAPI which was then renamed to PATA (Parallel ATA). Then new revised version launched named as Serial ATA or SATA.
Actually when I started working on computers we were having IDE Drives in it, which was having Master and Slave concept. Now we have SATA drives which are limited by the number of channels provided by the controller.
Everybody started using the drives and Storage as per their requirements and budget. We can differentiate “SATA version 1.x, 2.x, 3.x, SAS, SCSI Altra and then fibre Channel over fiber optic and copper cable” these interfaces with Raw Bandwidth, Max Transfer Speed, Devices per Channel limitations.
Now companies having high Storage requirements and also if they cannot compromise with the performance they decide the storage devices as per Storage Tier features. Some of them are listed below :
That’s it for now, we have a lot to learn about Storage, specifically how it works with VMware. I hope you liked the information.