Humm, the Maxtor spec I am looking at does not limit the duty cycle. It makes no reference at all. I think it is reasonable to assume 24 hours per day, unless they claim less. The drive should fail on average of once per 114 years, but end of life is 3-5 years? I did find this on the Maxtor web site: No MTBF, but ARR of <1%. I think they are saying if I had 100 drives less than 1 failure per year. That is a MTFB of more than 100 years. Design life (min) 5 years. So, the disk should last al least 5 years. I have no problem with this. If this is running time, not time powered off. No limits on duty cycle listed, so got to assume 24/7. So, if I had 100 disks that lasted at least 5 years with less than 1 failure per year... I would be happy. After all, in 5 years I could replace the 100 drives with 6 new drives with the same total capacity. This is based on drive size doubling every 1.5 years. Of course my requirements double every year! :) http://maxtor.com/_files/maxtor/en_us/documentation/data_sheets/diamondmax_1 0_data_sheet.pdf Now if someone made an affordable tape drive and tapes that could backup 200G per tape, that would be cool! Guy -----Original Message----- From: Mark Klarzynski [mailto:mark.k@xxxxxxxxxxxxxxxxxxxxx] Sent: Saturday, November 20, 2004 3:03 PM To: 'Guy' Subject: RE: Good news / bad news - The joys of RAID MTBF is statistic based upon the expected 'use' of the drive and the replacement of the drive after its end of life (3-5 years)... It's extremely complex and boring but the figure is only relative if the drive is being used within an environment that matches those of the calculations. SATA / IDE drives have an MTBF similar to that of SCSI / Fibre. But this is based upon their expected use... i.e. SCSI used to be [power on hours = 24hr] [use = 8 hours].. whilst SATA used to be [power on = 8 hours] and [use = 20 mins]. Regardless of what some people clam (usually those that only sell sata based raids), the drives are not constructed the same in any way. SATA's fail more within a raid environment (probably around 10:1) because of the heavy use and also because they are not as intelligent... therefore when they do not respond we have no way of interrogating them or resetting them, whilst with scsi we do both. This means that a raid controller / driver has no option to but simply fail the drive. Maxtor lead the way in capacity and also reliability... I personal had to recall countless earlier IBMs and replace them with maxtor. But the new generation of IBM's (Hitachi) have got it together. So - I guess you are all right :) -----Original Message----- From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid-owner@xxxxxxxxxxxxxxx] On Behalf Of Guy Sent: 20 November 2004 19:38 To: 'Mark Hahn'; linux-raid@xxxxxxxxxxxxxxx Subject: RE: Good news / bad news - The joys of RAID I have had far more failures of Maxtor drives than any other. I have also had problems with WD drives. I know someone that had 4-6 IBM disks, most of which have failed. I am talking about disks with 3 year warranties! Based on the spec. But OEM disks have none. You must return them to the PC manufacture. Most of my failures were within 3 years, but beyond the warranty period of the system. So the OEM issue has occurred too often. I have had good luck with Seagate. I use RAID, it is a must with the failure rate! I do backup also, but RAID tends to save me. Most people have a PC with 1 disk. I don't understand RAID, and they don't understand that everything will be lost if the disk breaks! They think "Dell will just fix it". But wrong, Dell will just replace it! Big difference. Today's disks claim a MTBF of about 1,000,000 hours! That's about 114 years. So, if I had 10 disks I should expect 1 failure every 11.4 years. That would be so cool! But not in the real world. Can you explain how the disks have a MTBF of 1,000,000 hours? But fail more often than that? Maybe I just don't understand some aspect of MTBF. Guy -----Original Message----- From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid-owner@xxxxxxxxxxxxxxx] On Behalf Of Mark Hahn Sent: Saturday, November 20, 2004 1:43 PM To: linux-raid@xxxxxxxxxxxxxxx Subject: RE: Good news / bad news - The joys of RAID > Never buy Maxtor drives again! you imply that Maxtor drives are somehow inherently flawed. can you explain why you think millions of people/companies are naive idiots for continuing to buy Maxtor disks? this sort of thing is just not plausible: Maxtor competes with the other top-tier disk vendors with similar products and prices and reliability. yes, if you buy a 1-year disk, you can expect it to have been less carefully tested, possibly be of lower-end design and reliability, and to have been handle more poorly by the supply chain. thankfully, you don't have to buy 1-year disks any more. read the specs. make sure your supply chain knows how to handle disks. make sure your disks are mounted correctly, both mechanically and with enough airflow. use raid and some form of archiving/backups. don't get hung up on which of the 4-5 top-tier vendors makes your disk. - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
