Hi, I have a 4-drive RAID-10 array. I've been using mdadm for awhile to manage the array, and replace drives as they die without changing anything. Now, I want to increase its size in-place. I'd like to ask for some help with a review of my setup and plans on how to do it right. I'm really open to any advice that'll help me get there without blowing this all up! My array is cat /proc/mdstat ... md2 : active raid10 sdd1[1] sdc1[0] sde1[4] sdf1[3] 1953519616 blocks super 1.2 512K chunks 2 far-copies [4/4] [UUUU] bitmap: 0/466 pages [0KB], 2048KB chunk ... it's comprised of 4 drives; each is 1TB physical size, partitioned with a single 'max size' partition, where that partition is formatted 'Linux raid autodetect' fdisk -l /dev/sd[cdef] Disk /dev/sdc: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x00000000 Device Boot Start End Sectors Size Id Type /dev/sdc1 63 1953520064 1953520002 931.5G fd Linux raid autodetect Disk /dev/sdd: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x00000000 Device Boot Start End Sectors Size Id Type /dev/sdd1 63 1953520064 1953520002 931.5G fd Linux raid autodetect Disk /dev/sde: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x00000000 Device Boot Start End Sectors Size Id Type /dev/sde1 63 1953520064 1953520002 931.5G fd Linux raid autodetect Disk /dev/sdf: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x00000000 Device Boot Start End Sectors Size Id Type /dev/sdf1 63 1953520064 1953520002 931.5G fd Linux raid autodetect the array contains only/multiple LVs, in a RAID-10 array size of 2TB, pvs /dev/md2 PV VG Fmt Attr PSize PFree /dev/md2 VGBKUP lvm2 a-- 1.82t 45.56g vgs VGBKUP VG #PV #LV #SN Attr VSize VFree VGBKUP 1 8 0 wz--n- 1.82t 45.56g lvs VGBKUP LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert LV001 VGBKUP -wi-ao--- 1.46t LV002 VGBKUP -wi-ao--- 300.00g LV003 VGBKUP -wi-ao--- 160.00m LV004 VGBKUP -wi-ao--- 12.00g LV005 VGBKUP -wi-ao--- 512.00m LV006 VGBKUP -wi-a---- 160.00m LV007 VGBKUP -wi-a---- 4.00g LV008 VGBKUP -wi-a---- 512.00m where, currently, ~45.56G of the phy dev is unused I've purchased 4 new 3TB drives. I want to upgrade the existing array of 4x1TB drives to 4x3TB drives. I want to end up with a single partition, @ max_size == ~ 3TB. I'd like to do this *in-place*, never bringing down the array. Iiuc, this IS doable. 1st, I think the following procedure starts the process correctly: (1) format each new 3TB drive, with one 1TB partition, as 'linux raid autodetect', making sure it's IDENTICAL to the partition layout on the current array's disks (2) with the current array up & running, mdadm FAIL one drive (3) mdadm remove the FAIL'd drive from the array (4) physically remove the FAIL'd drive (5) physically insert the new, pre-formatted 3TB drive (6) mdadm add the newly inserted drive (7) allow the array to rebuild, until 'cat /proc/mdstat' says it's done (8) repeat steps (2) - (7) for each of the three remaining drives. 2nd, I have to correctly/safely to, in 'some' order extend the physical partitions on all four drives, or of the array (not sure which) extend the volume group on the array expand, or add, the existing LVMs in the volume group. I'm really not sure about what steps, in what order to do *here*. Can anyone verify that my first part is right, and help me out with doing the 2nd part right? Thanks a lot! Terry -- 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
