Questions to ask when making storage purchase decisions, part 2
I'm busy with research for a telecommunication company that wants to implement a SAN/NAS solution. I have to evaluate different top storage vendors to give the company the best solution.
My question is, what terms do I need to take in consideration for my research?
Click here for part 1
Here are some of the basic questions that need to be asked:
Does your storage support RAID? What RAID types does your storage
What is the name and model number of your array products?
What is the maximum usable capacity (in gigabytes; GB) for a single
How many global spares does your array support?
What is the mean time between failure of the parts in the array?
Do you support internal disk copies for backup and recovery?
Do you support array-based remote copy, and if so, does the copy
solution provide database write order fidelity over distance?
What is the maximum amount of servers that can connect to a single
How many logical unit numbers (LUNs) does your array support, and
what are the minimum and maximum sizes that can be created.
What types of connections do you support... FICON, ESCON, SCSI, FC?
How many physical connections are available?
Are your FC connections 1Gbit or 2Gbit?
What are your future plans for 10Gbit?
Do you support iSCSI connection?
What SAN extenders do you support for remote SAN connections?
What storage management solutions do you provide, or are compatible
What is your best practice fan-in-ratio per storage port?
What HBA's do you certify?
Do I have to buy all the components from you, or do you certify off the shelf SAN components from other vendors?
What operating systems do you support?
What clustering technology is certified to be used with your
What are the on-going costs for maintenance and configuration
Can your microcode be updated while my servers are online, or do I
need to take everything down?
Do you provide path-failover software, and if you do, how does it
work, and what are the timings for failover?
How do you handle SAN security?
Does your solution "Phone Home" when there is a problem?
Can I use my current management framework (Tivoli, CA, Openview,
BMC...) with your storage?
These are but a few of the questions that need to be asked if you want to be sure you did your due diligence when selecting a vendor. When you have finalized your short list of vendors, you should then have each of them bring in its solution so you can test it out through a "Proof Of Concept." Ask the vendor if you can do a "Try and Buy", so that if its claims are not supportable by reality, you can send it back at no cost to you.
I have a complete chapter covering the basics of an RFI (Request for
Information) in Chapter 15 of my book "Storage Area Networks for Dummies", that covers this topic in much greater detail. I hope this helps you in your decision making process for now though and congratulations on your choice of installing a new SAN solution. You will find that managing storage will become so much easier and the solution will have a financial payback in months.
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This was first published in June 2003