On Fri, 2011-06-24 at 00:35 -0500, Stan Hoeppner wrote: > On 6/23/2011 1:43 PM, Krzysztof Adamski wrote: > > Hi All, > > > > I have a raid6 array made out of 8 1.5T drives and I wanted to change to > > use 3T drives. The array is 0.90. After reading the wiki I see that 0.90 > > superblock will not work with any device larger then 2T. > > > > What are my options for a live upgrade (backup/restore is not possible)? > > The best way to do this, given that you have no backup, is to add a > known-to-work-with-Linux SAS/SATA HBA and build a new md array and > format it with a fresh filesystem. Let the 8 new drives spin for a > couple of days. If all 8 drives are still kicking, copy everything over > from the current filesystem with a 'cp -a' or similar method. If you > have NFS/Samba shares or other filesystem specific mappings, rsync, etc, > edit your conf files to point to the new filesystem/device. Run in > production with the new array for a few days or a week to make sure it's > working correctly, then remove the old array at your leisure. I was afraid of this. I only have 4 empty drive bays in my Norco 4220 case, I will have to shut down the second array and remove it during the time I'm upgrading. I will also have to get an HBA that supports 3T drives. > This staged multi step approach gives you the best chance to avoid data > loss during the migration as even after it's complete you still have the > existing array fully intact until you decide to remove it. It is much > safer than rebuilding an 8 disk array one disk at a time. It also puts > much less wear and tear on the new drives. Another benefit is that > after copying the files over, the new filesystem will be much less > fragmented than in the case of rebuilding the existing array one drive > at a time. I have before upgrade a 5 drive array one drive at a time without problems, but the new drives were only 2T. > If you don't have 16 disk bays and sufficient SAS/SATA ports in your > current chassis, and you can't leave a side panel off with the 8 new > drives simply sitting on a desk during the transition, then you should > grab an external enclosure, either desktop or rackmount, whichever fits > your needs, and an external version of the HBA. Some options are: > > If you have 16 bays or can sit the new 8 drives on the desk next to the > server during the upgrade just grab one of these cheap LSI based Intel 8 > port HBAs: > > http://www.newegg.com/Product/Product.aspx?Item=N82E16816117157 This card is based on 1068E chip, it does not support drives larger then 2T. I already have 2 LSI cards based on the same chip and I will need to upgrade. > > If you must go external, take a look at these. A bit more costly, but a > better solution in the long run. It'll also allow you to keep your > existing array instead of replacing it. If you go with the rackmount > unit adding a 4 port HBA in the future will allow you to add 4 more > drives. Each row of 4 drives has its own SFF8088 port on the back. > > http://www.newegg.com/Product/Product.aspx?Item=N82E16816118116 > http://www.newegg.com/Product/Product.aspx?Item=N82E16816111092 > http://www.newegg.com/Product/Product.aspx?Item=N82E16816133044 > -- 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
