Solved

A whole iSCSI SAN failure ?

Posted on 2013-02-07
2
326 Views
Last Modified: 2013-02-09
Hi,

Have anyone experienced a whole SAN failure due by any reason ?
The general thinking is that "anything can fail" makes a person uncomfortable with
having everything in a single SAN.
I was told to double a SAN which means having two identical SANs with some sorts of replication to protect data in case a whole SAN failure.
In each SAN, I also have multipath IO, dual controller, dual switches...etc ?
Is it a overkill ?

Thanks for any idea out there.
0
Comment
Question by:nothienthu
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 
LVL 4

Expert Comment

by:tpitch-ssemc
ID: 38864008
Everything you listed I would call normal. I'd make sure you also have multiple arrays with hot spares at a minimum. Budget depending, I'd also get another SAN and replicate everything over for your DR plans. I will not run a SAN unless I have 2 controllers connected to different switches.

For example, I had an EMC VNX that had 2 controllers with 4 iSCSI NICs each. Of the 4 iSCSI NICs I would have 2 going to switch A and 2 going to Switch B then I would do the same thing for the other controller. That way if I lost a switch I would only lose 50% of our paths.

Of course 2 SANs are better than 1.
0
 
LVL 10

Accepted Solution

by:
millardjk earned 500 total points
ID: 38867714
Yes, whole array failures occur. It's typically unrelated to the hardware, but instead due to some unknown bug in the firmware that causes catastrophic data loss.
In those scenarios, they often trigger cascading data loss in replicated arrays (garbage in, garbage out), and the only thing saving the business using them is a good set of backups.

Those tend to be doomsday scenarios, however. You can read about them occurring, however, so it is something to assign a level of risk when designing your failure scenarios.

So yes, consider duplicate SANs as one mode of risk avoidance; having duplicate connectivity gear and multiple paths is another; multiple hosts running hypervisors and UPS backed by generator are yet others. It all comes down to how much cash you can afford to spend on them, and whether there is additional value (like providing more capacity or performance) beyond that of eliminating a single point of failure.
0

Featured Post

Comprehensive Backup Solutions for Microsoft

Acronis protects the complete Microsoft technology stack: Windows Server, Windows PC, laptop and Surface data; Microsoft business applications; Microsoft Hyper-V; Azure VMs; Microsoft Windows Server 2016; Microsoft Exchange 2016 and SQL Server 2016.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Backing up data is essential for any office small or large. Most think that a simple USB drive will suffice. Even the USB drives themselves display words like backup.   Most novices will ask themselves the question “Will this work for my business…
From Coral's  "So You Want To Play With Computers" Series Preface: What follows is a tweaked reprint from 2005/06. This is a True Story. The names have been changed to protect the guilty. While this deals with a fairly simple, text file recovery…
This tutorial will walk an individual through the steps necessary to configure their installation of BackupExec 2012 to use network shared disk space. Verify that the path to the shared storage is valid and that data can be written to that location:…
This tutorial will walk an individual through configuring a drive on a Windows Server 2008 to perform shadow copies in order to quickly recover deleted files and folders. Click on Start and then select Computer to view the available drives on the se…

756 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question