md checks its part only, as far as I know. It makes sense since it would be checking the integrity of the array's disks/partitions. If you want the disks to undergo full check up, I'd suggest you run smartd and run both short self tests and offline tests. Offline tests take a very long time because they do thorough tests. Make sure you setup smartd to email you on reports/problems so that you can find bad sectors as soon as they happen and fix them asap. On Tue, Sep 22, 2009 at 6:38 PM, Jon Hardcastle <jd_hardcastle@xxxxxxxxx> wrote: > Some good suggestions here, thanks guys. > > Do I >DID< imagine some built in support for making use of this space? > > As a side note. when i do a repair or check on my array.. does it check the WHOLE DRIVE.. or just the part that is being used? I.e. in my case.. I have a 1TB drive but only an array multiple of 500GB.. i'd like to think it is checking the whole whack as it may have to take over some day... > > ----------------------- > N: Jon Hardcastle > E: Jon@xxxxxxxxxxxxxxx > 'Do not worry about tomorrow, for tomorrow will bring worries of its own.' > ----------------------- > > > --- On Tue, 22/9/09, Majed B. <majedb@xxxxxxxxx> wrote: > >> From: Majed B. <majedb@xxxxxxxxx> >> Subject: Re: Full use of varying drive sizes? >> To: "Linux RAID" <linux-raid@xxxxxxxxxxxxxxx> >> Date: Tuesday, 22 September, 2009, 2:07 PM >> When I first put up a storage box, it >> was built out of 4x 500GB disks, >> later on, I expanded to 1TB disks. >> >> What I did was partition the 1TB disks into 2x 500GB >> partitions, then >> create 2 RAID arrays: Each array out of partitions: >> md0: sda1, sdb1, sdc1, ...etc. >> md1: sda2, sdb2, sdc2, ...etc. >> >> All of those below LVM. >> >> This worked for a while, but when more 1TB disks started >> making way >> into the array, performance dropped because the disk had to >> read from >> 2 partitions on the same disk, and even worse: When a disk >> fail, both >> arrays were affected, and things only got nastier and worse >> with time. >> >> I would not recommend that you create arrays of partitions >> that rely >> on each other. >> >> I do find the JBOD -> Mirror approach suggested earlier >> to be convenient though. >> >> On Tue, Sep 22, 2009 at 3:58 PM, John Robinson >> <john.robinson@xxxxxxxxxxxxxxxx> >> wrote: >> > On 22/09/2009 12:52, Kristleifur Dađason wrote: >> >> >> >> On Tue, Sep 22, 2009 at 11:24 AM, Jon Hardcastle >> >> <jd_hardcastle@xxxxxxxxx> >> wrote: >> >>> >> >>> Hey guys, >> >>> >> >>> I have an array made of many drive sizes >> ranging from 500GB to 1TB and I >> >>> appreciate that the array can only be a >> multiple of the smallest - I use the >> >>> differing sizes as i just buy the best value >> drive at the time and hope that >> >>> as i phase out the old drives I can '--grow' >> the array. That is all fine and >> >>> dandy. >> >>> >> >>> But could someone tell me, did I dream that >> there might one day be >> >>> support to allow you to actually use that >> unused space in the array? Because >> >>> that would be awesome! (if a little hairy re: >> spare drives - have to be the >> >>> size of the largest drive in the array >> atleast..?) I have 3x500GB 2x750GB >> >>> 1x1TB so I have 1TB of completely unused >> space! >> >> >> >> Here's a thought: >> >> Imaginary case: Say you have a 500, a 1000 and a >> 1500 GB drive. You >> >> could JBOD the 500 and the 1000 together and >> mirror that against the >> >> 1500GB. >> >> >> >> Disclaimer: >> >> I don't know if it makes any sense to do this. I >> haven't seen this >> >> method mentioned before, IIRC. It may be too >> esoteric to get any >> >> press, or it may be simply stupid. >> > >> > Sure you can do that. In Jon's case, a RAID-5 across >> all 6 discs using the >> > first 500GB, leaving 2 x 250GB and 1x 500GB free. The >> 2 x 250GB could be >> > JBOD'ed together and mirrored against the 500GB, >> giving another 500GB of >> > usable storage. The two md arrays can in turn be >> JBOD'ed or perhaps better >> > LVM'ed together. >> > >> > Another approach would be to have another RAID-5 >> across the 3 larger drives, >> > again providing an additional 500GB of usable storage, >> this time leaving 1 x >> > 250GB wasted, but available if another 1TB drive was >> added. I think this may >> > be the approach Netgear's X-RAID 2 takes to using >> mixed-size discs: >> > http://www.readynas.com/?p=656 >> > >> > Cheers, >> > >> > John. >> > -- >> > 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 >> > >> >> >> >> -- >> Majed B. >> -- >> 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 >> > > > > -- Majed B. -- 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
