RE: Any reason to go RAID6 vs RAID10? It depends on performance needs and how comfortable you are with data loss. Consider the following situation for your 6 disk array. In this RAID6 configuration, you can loose 2 disks, any 2 disks, and not loose any data. Now in RAID 1+0 (or 0+1) you have 2 pairs of identical stripes (in this instance 2x 3 disk stripes). If you lose a disk in both stripes, your data is gone. So the right 2 drives failing can take out all your data.
A 6 spindle RAID10 array will be considerably quicker than the same spindle count RAID6 array due to architecture as well as reduced CPU overhead (there's no parity calculation in RAID10, just an additional write, while you have to make 2 parity calculations for every write in RAID6). My advice would be to use all 8 bays as a RAID6 array (7 drives in the array and one hot spare) and then take full advantage AWS/Azure/Backblaze/Crashplan/etc for offsite archival and backup. Nathan Shelby Lead Systems Engineer – Quote Wizard <https://quotewizard.com/> [email protected] / 206-753-2626 Malo Periculosam Libertatem Quam Quietum Servitium On Tue, Jan 20, 2015 at 5:49 PM, J- P <[email protected]> wrote: > Any reason to go raid 6 vs raid 10? > > > > ------------------------------ > From: [email protected] > To: [email protected] > Subject: RE: [NTSysADM] SHR vs Traditional RAID/RED drives > Date: Wed, 21 Jan 2015 01:43:04 +0000 > > Just to add: My Synology DS2413+ got corrupted about a year ago and I > effectively lost all of my data. At that time, I posed the question to > Synology as to what they recommended when I set up the server again – SHR2 > or RAID6. I was informed that while both options technically will work, > they recommended RAID 6 over SHR2 for 7 or more hard drives for > reliability. > > > > -Aakash Shah > > > > *From:* [email protected] [mailto: > [email protected]] *On Behalf Of *James Button > *Sent:* Tuesday, January 20, 2015 9:39 AM > *To:* [email protected] > *Subject:* RE: [NTSysADM] SHR vs Traditional RAID/RED drives > > > > My point is that you need to have a reasonable recovery concept (and > frequently proven process) to deal with a hard drive failing – mirror or > rebuildable striping > > And that should include the possibility that it may be the NAS housing > that fails – possibly taking the drives with it. > > And the data on the still OK drives not being in a structure accessible > by any other OS you have to hand. > > > > Yes – if you need speed striping etc. or maybe a large set of small drives > ( 2¼” laptop ones maybe – TomsHardware did a project a long while ago > comparing throughput on a large number of small drives vs a small number of > large drives, and the conclusion was the small drives option was much > faster, used a lot less power just needed more PSU and connection > considerations - as in massed add-in drive controller boards. > > > > For those considering faster storage access – SSD is the easy way, > alternatively go the volume way or ‘attach’ partitions of several drives as > folders of an NTFS OS/filestore partition/drive. > > > > HOWEVER – do make sure that : > > 1) The PSU can manage the drives powering up at system startup. > > 2) The BIOS can manage the drives – maybe delay/sequenced power up > at system startup. > > 3) The OS can manage that much MFT data being scanned etc. at > startup. > > 4) There is sufficient real memory to manage the combined MFT data > without massive paging of memory > > > > I have a win7 ultimate system that gets itself into knots if there are > more than 2 2TB drives USB attached at startup. > > It happily runs with 5 drives attached if they are started up sequentially > – as in wait for the windows explorer to sho a drive before connecting the > next – and connecting means the interface cable, not just the power-brick > > > > > > JimB > > > > > > > > *From:* [email protected] [ > mailto:[email protected] <[email protected]>] *On > Behalf Of *J- P > *Sent:* Tuesday, January 20, 2015 5:09 PM > *To:* NT > *Subject:* RE: [NTSysADM] SHR vs Traditional RAID/RED drives > > > > My initial thought was raid 10 using 4tb (as thats what I use for > servers) but I was reading about their SHR and it sounded interesting in > that you can use different size drives and not lose any space > > The MEDIA data that is stored, is not "active" they do a job, transfer it > there, after 6 months it gets erased. > > but I plan to use the additional storage for doing local server backups as > well. (I do back up there servers off-site but its not realistic to pull > 3TB over the wire). > > MY thought was 6 drives in raid10, then use the 2 remainig drives to copy > what is deemed critical off the raid10 > > > > ------------------------------ > > Date: Tue, 20 Jan 2015 08:44:00 -0800 > Subject: Re: [NTSysADM] SHR vs Traditional RAID/RED drives > From: [email protected] > To: [email protected] > > The WD NAS drives are only rated for groups of up to 6 and aimed squarely > at the consumer market. They're rated for something along the lines of > 180TB/year and only an error rate of 1x10^14. > > > > The Red Pro drives are slightly better and built for 8-16 bay units backed > by a 5 year warranty, have a 7.2K speed and a much better 1x10^15 error > rate and warrantied for 550TB/year written, also dropping in capacity to > 4TB. > > > > If data is critical then move to their WD RE series drives again a > 550TB/year rating along with 7.2K spindle and 5 year warranty with an even > better 1x10^16 error rate. > > > > If you need the density you pay for it in reliability currently, be > prepared to keep multiple copies. You mentioned 'terabytes of data' - how > hot/cold is it? > > > > Also if you're using anything above 1TB drives please don't use RAID5 > you'll just be kicking yourself later :( > > > Nathan Shelby > Lead Systems Engineer – Quote Wizard <https://quotewizard.com/> > [email protected] / 206-753-2626 > Malo Periculosam Libertatem Quam Quietum Servitium > > > > On Tue, Jan 20, 2015 at 8:00 AM, J- P <[email protected]> wrote: > > Hi all, > > I'm looking to drop one of these in at customer site, > https://www.synology.com/en-us/products/DS1815+ > I'm curious to know if anyone has elected to use their proprietary raid > SHR/SHR2, and if so how it stacks up to traditional raid in terms of > performance. > > And on a separate note , has anyone jumped onto the WD RED "NAS" drives > yet? > > I like the idea of 6TB for 270.00, but not crazy about 54k speed or 3 yr > warranty > > http://www.amazon.com/Western-Digital-3-5-inch-IntelliPower-WD60EFRX/dp/B00LO3KR96/ref=pd_bxgy_pc_text_y > > however , 226.00 for a 4TB 72k with a 5 year warranty does sit a little > better > > http://www.amazon.com/dp/B00LO3KRM8 > > any feedback is appreciated > > >
