Drew Wutka
DWUTKA at Marlow.com
Wed Jul 21 16:47:09 CDT 2010
A few months ago, saw a network capable RAID 1 hard drive setup for ~$200, without the drives. Just a box with a network port. Terrabyte drives are getting pretty cheap, so you could get a networked mirrored 1+ terabyte setup for about 400. Drew -----Original Message----- From: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com] On Behalf Of Michael Bahr Sent: Wednesday, July 21, 2010 12:42 PM To: Access Developers discussion and problem solving Subject: Re: [AccessD] Google's Disk Failure Experience Well, I can see your point that only ripping DVD's takes 2 minutes each and you do not need them anymore. But for me I record OTA/cable HD shows and uncut movies and cut out the commercials and archive them. Now I have whole seasons worth of shows and movies. I save money buy not buying the Blu-Ray disks ($30-$60 for each season or movie). So yes it is important to me to have a backup as these are not reproducible. A seperate media server setup as raid 1 does fit my needs. Mike... > >How much is your time worth? > > This is a classic case of insufficient analysis... > > The cost is not the cost of the drive. It is the cost of the drive (twice > the drives), plus the > cost of the SATA ports (twice) plus the cost of the power supply (twice > the disk current - 12v), > plus the cost of electricity to run the disks (twice the electricity) plus > the cost of a case big > enough to handle enough drives (twice as large disk cage) plus... > > Of course all my "twices" are on a "per disk used" basis, not a total > system cost and I understand > the difference. > > Furthermore, my time isn't the cost of my time to rip 200 dvds, it is the > cost of my time to rip 200 > dvds divided by the probability of losing 2 disks at the same time. > > I ripped my drives as I wanted to watch them, so it was an incremental > cost accumulated over time. > The actual time is about 2 minutes per dvd. 200 dvds per drive is an > actual cost of 200 minutes to > fill a drive. Would I actually rerip all of the disks? No because many > of them are for my kids who > are now older and don't even watch those disks any more, not to mention > the disks I ripped that I > just don't care about. > > HOWEVER... In the two years that I have been using the system, I have > never lost one of these > drives. Thus my time to "do it over again" is zero (so far). I have been > working with raid > extensively for about 5 years, and in those 5 years I have lost single > drives but I have never lost > two drives at the same time. > > I am sure that there are numbers out there that discuss the probability of > two drive failures. In > fact IIRC from that paper by google, the probability of failure of any > given single drive over 5 > years was about 14%? The probability of two failures (my simple math) > would be .14 * .14 = .0196 or > ~ 2%. That is for two failures, NOT two SIMULTANEOUS failures. > > All of this matters if the cost is catastrophic. Facing a 2% chance that > I will have to re-rip 200 > dvds in any given 5 year period, I am unwilling to commit the extra money > to preventing this > possibility. > > This whole discussion does point out that an analysis of the actual > numbers might cause one to come > to a different conclusion. And who knows, you might decide "screw the > costs", it is worth it to me. > > It is not worth it to me. > > Look at Unraid. > > http://lime-technology.com/ > > I am not trying to sell anyone on unRaid, I am simply saying consider it > for a specific class of > redundancy needs. For this level of redundancy need, unRaid seems like a > good compromise. > > John W. Colby > www.ColbyConsulting.com > > > Michael Bahr wrote: >> John, for your media collections you really should go only Raid 1. Yeah >> if you lose the HD you can re-do everything but who has the time? >> Besides >> 2TB HD's are ~<$150 or so. How much is your time worth? >> >> Mike... >> >>> I am about to build an UnRaid for my massive video / music collection. >>> I >>> currently have no >>> protection on that so if I lose a disk I lose all of that on one disk. >>> With Unraid I >>> would have "raid 5 like" >>> storage so that in the event of single drive failure I can still >>> recover. >>> If I do lose it I just >>> re-rip. Not the end of the world but not something I want to do. >>> >>> John W. Colby >>> www.ColbyConsulting.com > > -- > AccessD mailing list > AccessD at databaseadvisors.com > http://databaseadvisors.com/mailman/listinfo/accessd > Website: http://www.databaseadvisors.com > -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com The information contained in this transmission is intended only for the person or entity to which it is addressed and may contain II-VI Proprietary and/or II-VI Business Sensitive material. If you are not the intended recipient, please contact the sender immediately and destroy the material in its entirety, whether electronic or hard copy. You are notified that any review, retransmission, copying, disclosure, dissemination, or other use of, or taking of any action in reliance upon this information by persons or entities other than the intended recipient is prohibited.