INTRODUCTION OF SAN
SAN (Storage Area Network) is storage product of IBM which provides dedicated network to block level data storage. SANs are primarily used to make storage devices, such as disk arrays, tape libraries, and optical jukeboxes, accessible to servers so that the devices appear like locally attached devices to the operating system.
1. Internal Storage
- Internal Disks within the Servers
2. Directly Attached (JBOD)
- External Chassis of Disks connected to a Server via a Cable (SCSI or Fiber Channel)
3. Directly Attached Shared
- External Chassis connected to more than one Server via a Cable.
4. SAN (Storage Area Network)
5. NAS (Networked Attached Storage)
6. Networked Storage (NAS + SAN)
7. CAS (Content Addressable Storage)
Data centers first created “islands” of SCSI disk arrays as direct-attached storage (DAS), each dedicated to an application, and visible as a number of “virtual hard drives” (i.e. LUNs). Essentially, a SAN consolidates such storage islands together using a high-speed network.
Operating systems maintain their own file systems on their own dedicated, non-shared LUNs, as though they were local to themselves. If multiple systems were simply to attempt to share a LUN, these would interfere with each other and quickly corrupt the data. Any planned sharing of data on different computers within a LUN requires advanced solutions, such as SAN file systemsor clustered computing.
Despite such issues, SANs help to increase storage capacity utilization, since multiple servers consolidate their private storage space onto the disk arrays. Common uses of a SAN include provision of transactionally accessed data that require high-speed block-level access to the hard drives such as email servers, databases, and high usage file servers.
Network-attached storage (NAS ), in contrast to SAN, uses file-based protocols such as NFS or SMB/CIFS where it is clear that the storage is remote, and computers request a portion of an abstract file rather than a disk block.
BENEFITS OF SAN TO INDUSTRY:
- Sharing storage usually simplifies storage administration and adds flexibility since cables and storage devices do not have to be physically moved to shift storage from one server to another.
- SAN has the ability to allow servers to boot from the SAN itself. This allows for a quick and easy replacement of faulty servers since the SAN can be reconfigured so that a replacement server can use the LUN of the faulty server. While this area of technology is still new many view it as being the future of the enterprise datacenter.
- SANs also tend to enable more effective disaster recovery processes.
- The Fiber Channel over IP (FCIP) and iSCSI protocols have been developed to allow SAN extension over IP networks.
IBM Categorized as Entry Level (DS3500 Exp, EXP2500 Express,EXP3000), Midrange (DCS3700,DS5000 series, IBM Storwize V7000 Unified Storage) and Enterprise (DS8000,IBM XIV, SONAS ) Storages based on the data volume of business segment.
DAILY ACTIVITIES OF IBM-SAN ADMINISTRATOR:
Any Administrator commonly work as L1 Support, L2 Support, L3 Support depending on his experience. Based on his position he will be allocated with pre-defined privilages and they commonly perform following tasks:
Disk space allocation to various Host
Configuration of the disk
Zoning and Mapping
Configuration of logical unit numbers (LUN) to allow systems to perform at optimal level
Back-up and restore
Installs patches or upgrades to the server’s hardware, firmware or software
Perform troubleshooting and performance monitoring of SAN environment.
Supporting SAN fiber channel switches
Performing Health Checks on all the SAN devices in the environment
Storage Administrative tasks like LUN Allocation, Raid Group Creation, LUN/Raid Group Expansion, LUNMigration etc.
HOW SAN LOOKS LIKE?
Click Here To See IBM-SAN