Storage Latest Interview FAQs - TOP SAN Interview Questions and Answers
> What is the need for separate network for storage why LAN can't be used?
LAN hardware and operating systems are geared to user traffic, and LANs are tuned for a fast user response to messaging requests.
With a SAN, the storage units can be secured separately from the servers and totally apart from the user network enhancing storage access in data blocks (bulk data transfers), advantageous for server less backups.
> What are the types of disk array used in SAN? JBOD: Just Bunch of Disks is Storage Box,it consists of Enclosure where set of harddrives are hosted in many combinations such SCSI drives,SAS ,FC,SATA.
RAID: (Redundant Array of Inexpensive Disks) Technology that groups several physical drives in a computer into an array that you can define as one or more logical drive to achieve redundancy with fasterI/O.
> Differentiate RAID & JBOD? RAID: "Redundant Array of Inexpensive Disks"
= Fault-tolerant grouping of disks that server sees as a single disk volume
= Combination of parity-checking, mirroring, striping
= Self-contained, manageable unit of storage
JBOD: "Just a Bunch of Disks"
= Drives independently attached to the I/O channel
= Scalable, but requires server to manage multiple volumes
= Do not provide protection in case of drive failure.
> What is zoning?
Fabric management service that can be used to create logical subsets of devices within a SAN. This enables portioning of resources for management and access control purpose.
> What are the two major classification of zoning?
Two types of zoning are:
a) Software Zoning.
b) Hardware Zoning.
> What are different levels of zoning?
a) Port Level zoning.
b) WWN Level zoning.
c) Device Level zoning.
d) Protocol Level zoning.
e) LUN Level zoning.
> What are two types of recording techniques on the tapes?
a) Linear Recording
b) Helical Scan Recording.
> What is the different between mirroring, Routing and multipathing? Mirroring: Generates 2 ios to 2 storage targets Creates 2 copies of data. Routing: Determined by switches independent of SCSI Recreates n/w route after a failure. Multipathing: Two initiator to one target Selects the LUN initiator pair to use.