"I am looking to verify a RAID1 setup by examining the individual devices in the array" Are you trying to verify/check which devices are mirror pairs ? Why not take a md5sum and compare the ones you assume are mirrors? https://access.redhat.com/solutions/3253681 I doubt you can mount the underlying devices while the raid10 device is active. -Nikhil. On Sat, Apr 28, 2018 at 10:02 AM, Nick Leli <nicholasleli@xxxxxxxxx> wrote: > > Hi Folks, > > I am looking to verify a RAID1 setup by examining the individual > devices in the array, but having some issues. Here's is what I'm > working with: > > # cat /proc/mdstat > Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] > md2 : active raid1 sdb5[2] sda5[0] > 2925435456 blocks super 1.2 [2/2] [UU] > > md1 : active raid1 sdb2[1] sda2[0] > 2097088 blocks [2/2] [UU] > > md0 : active raid1 sdb1[1] sda1[0] > 2490176 blocks [2/2] [UU] > > # fdisk -l > Disk /dev/sda: 2.7 TiB, 3000592982016 bytes, 5860533168 sectors > Units: sectors of 1 * 512 = 512 bytes > Sector size (logical/physical): 512 bytes / 4096 bytes > I/O size (minimum/optimal): 4096 bytes / 4096 bytes > Disklabel type: gpt > Disk identifier: ADC4268A-1555-40E4-A684-B366EC60F94F > > Device Start End Sectors Size Type > /dev/sda1 2048 4982527 4980480 2.4G Linux RAID > /dev/sda2 4982528 9176831 4194304 2G Linux RAID > /dev/sda5 9453280 5860326239 5850872960 2.7T Linux RAID > ... > Disk /dev/sdb: 2.7 TiB, 3000592982016 bytes, 5860533168 sectors > Units: sectors of 1 * 512 = 512 bytes > Sector size (logical/physical): 512 bytes / 4096 bytes > I/O size (minimum/optimal): 4096 bytes / 4096 bytes > Disklabel type: gpt > Disk identifier: 229F0A5C-AF3E-4FC6-9C78-44F6B62E8843 > > Device Start End Sectors Size Type > /dev/sdb1 2048 4982527 4980480 2.4G Linux RAID > /dev/sdb2 4982528 9176831 4194304 2G Linux RAID > /dev/sdb5 9453280 5860326239 5850872960 2.7T Linux RAID > > The RAID is utilized with LVM, but I would like to inspect the > individual disks, to ensure that data is replicated in case of > failure. If I try to mount the individual drives, I run into issues: > > # mount /dev/sdb5 /tmp/sdb5/ > mount: unknown filesystem type 'linux_raid_member' > > These (sd[ab]) drives are not explicitly mounted (at least in > /proc/mounts), yet this seems to cause a problem. So I'm curious: > > 1. Is it possible to mount these devices, while a RAID array is active? > 2. If mounting is not possible, is there another way to verify that > each disk contains the correct data (besides /proc/mdstats or dd)? > -- > 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
