SAN Interview FAQs - TOP SAN Interview Questions and Answers
> What is SAN ?
A storage area network (SAN) is defined as a set of interconnected devices (e.g. disks and tapes) and servers that are connected to a common communication and data transfer infrastructure such as a fiber channel. The common communication and data transfer mechanism for a given deployment is commonly known as the storage fabric. The purpose of the SAN is to allow multiple servers access to a pool of storage in which any server can potentially access any storage unit.
> What is the difference b/w SAN and NAS ?
The basic difference between SAN and NAS , SAN is Fabric based and NAS is Ethernet based.
SAN – Storage Area Network
It accesses data on block level and produces space to host in form of disk.
NAS – Network attached Storage
It accesses data on file level and produces space to host in form of shared network folder.
> Can you briefly explain each of these Storage area components? Fabric Switch: It's a device which interconnects multiple network devices .There are swithes starting from 16 port to 32 ports which connect 16 or 32 machine nodes etc.Vendors who manufacture these kind of switches are Brocade, McData.
FC Controllers: These are Data transfer medias they will sit on PCI slots of Server,u can configure Arrays and volumes on it.
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.
> How is a SAN managed ?
There are many management softwares used for managing SAN's to name a few:
- IBM Tivoli Storage Manager.
- CA Unicenter.
- Veritas Volumemanger.
> What are the advantages of SAN?
- Massively extended scalability.
- Greatly enhanced device connectivity.
- Storage consolidation.
- LAN-free backup.
- Server-less (active-fabric) backup.
- Server clustering.
- Heterogeneous data sharing.
- Disaster recovery – Remote mirroring.
> Name some of the SAN topologies ?
Point-to-point, arbitrated loop, and switched fabric topologies.
> What are the benefits of fibre channel SANs?
Fibre Channel SANs are the de facto standard for storage networking in the corporate data center because they provide exceptional reliability, scalability, consolidation, and performance. Fibre Channel SANs provide significant advantages over direct-attached storage through improved storage utilization, higher data availability, reduced management costs, and highly scalable capacity and performance.
> What environment is most suitable for fibre channel SANs?
Typically, Fibre Channel SANs are most suitable for large data centers running business-critical data, as well as applications that require high-bandwidth performance such as medical imaging, streaming media, and large databases. Fibre Channel SAN solutions can easily scale to meet the most demanding performance and availability requirements.
> What Customer problem do fibre channel SAN solve?
The increased performance of Fibre Channel enables a highly effective backup and recovery approach, including LAN-free and server-free backup models. The result is a faster, more scalable, and more reliable backup and recovery solution. By providing flexible connectivity options and resource sharing, Fibre Channel SANs also greatly reduce the number of physical devices and disparate systems that must be purchased and managed, which can dramatically lower capital expenditures. Heterogeneous SAN management provides a single point of control for all devices on the SAN, lowering costs and freeing personnel to do other tasks.