If you are using /dev/sd[a-h] directly without partitions then you should not have partition tables on the devices. Your results indicate that there are partitions tables (the existence of the sd[a-h]1 devices and the MBR magic. Do "fdisk -l /dev/sd[a-h]", given 4tb devices they are probably GPT partitions. If they are GPT partitions more data gets overwritten and can cause limited data loss. Given these are 4tb disks I am going to suspect these are GPT partitions. Do not recreate the array, to do that you must have the correct device order and all other parameters for the raid correct. You will also need to determine how/what created the partitions. There are reports that some motherboards will "fix" disks without a partition table. if you dual boot into windows I believe it also wants to "fix" it. Read this doc that is written about how to recover, it has instructions of how to create overlays and those overlays allow you to test the different possible order/parameters without writing to the array until you figure out the right combination. https://raid.wiki.kernel.org/index.php/RAID_Recovery Because of these issues and other issues it is always best to use partition tables on the disks. On Fri, Mar 1, 2024 at 9:46 AM Topi Viljanen <tovi@xxxxxx> wrote: > > Hi, > > I have an RAID 6 array that is not having its 6 disks activated. Now > after reading more instructions it's clear that using webmin to create > RAID devices is a bad thing. You end up using the whole disk instead > of partitions of them. > > All 6 disks should be ok and data should be clean. The array broke > after I moved the server to another location (sata cables might be in > different order etc). The original reason for the changes was an USB > drive that broke up... yep, there were the backups. That broken disk > was in fstab and therefore ubuntu went to recovery mode (since disk > was not available). So backups are now kind of broken too. > > > Autodiscovery does find the array: > RAID level - RAID6 (Dual Distributed Parity) > Filesystem status - Inactive and not mounted > > > Here's report from mdadm examine: > > $ sudo mdadm --examine /dev/sd[c,b,d,e,f,g] > /dev/sdc: > Magic : a92b4efc > Version : 1.2 > Feature Map : 0x1 > Array UUID : 2bf6381b:fe19bdd4:9cc53ae7:5dce1630 > Name : NAS-ubuntu:0 > Creation Time : Thu May 18 22:56:47 2017 > Raid Level : raid6 > Raid Devices : 6 > > Avail Dev Size : 7813782192 sectors (3.64 TiB 4.00 TB) > Array Size : 15627548672 KiB (14.55 TiB 16.00 TB) > Used Dev Size : 7813774336 sectors (3.64 TiB 4.00 TB) > Data Offset : 254976 sectors > Super Offset : 8 sectors > Unused Space : before=254896 sectors, after=7856 sectors > State : clean > Device UUID : b944e546:6c1c3cf9:b3c6294a:effa679a > > Internal Bitmap : 8 sectors from superblock > Update Time : Wed Feb 28 19:10:03 2024 > Bad Block Log : 512 entries available at offset 24 sectors > Checksum : 4a9db132 - correct > Events : 477468 > > Layout : left-symmetric > Chunk Size : 512K > > Device Role : Active device 5 > Array State : AAAAAA ('A' == active, '.' == missing, 'R' == replacing) > /dev/sdb: > MBR Magic : aa55 > Partition[0] : 4294967295 sectors at 1 (type ee) > /dev/sdd: > MBR Magic : aa55 > Partition[0] : 4294967295 sectors at 1 (type ee) > /dev/sde: > MBR Magic : aa55 > Partition[0] : 4294967295 sectors at 1 (type ee) > /dev/sdf: > MBR Magic : aa55 > Partition[0] : 4294967295 sectors at 1 (type ee) > /dev/sdg: > MBR Magic : aa55 > Partition[0] : 4294967295 sectors at 1 (type ee) > > > > > Since the disks have been used instead of partitions I'm now getting > an error when trying to assemble: > > $ sudo mdadm --assemble /dev/md0 /dev/sdc /dev/sdb /dev/sdd /dev/sde > /dev/sdf /dev/sdg > mdadm: No super block found on /dev/sdb (Expected magic a92b4efc, got 00000000) > mdadm: no RAID superblock on /dev/sdb > mdadm: /dev/sdb has no superblock - assembly aborted > > $ sudo mdadm --assemble --force /dev/md0 /dev/sdb /dev/sdc /dev/sdd > /dev/sde /dev/sdf /dev/sdg > mdadm: Cannot assemble mbr metadata on /dev/sdb > mdadm: /dev/sdb has no superblock - assembly aborted > > > Should I try to re-create that array again or how can I activate it > properly? It seems that only 1 disk reports the array information > correctly. > > > ls /dev/sd* > /dev/sda /dev/sda1 /dev/sdb /dev/sdc /dev/sdd /dev/sde /dev/sdf > /dev/sdg /dev/sdh /dev/sdh1 > > All disks should be fine. I have setup a warning if any device fails > in the array and there have been no warnings. Also SMART data shows ok > for all disks. > > > Basic info: > > $uname -a > Linux NAS-server 5.15.0-97-generic #107-Ubuntu SMP Wed Feb 7 13:26:48 > UTC 2024 x86_64 x86_64 x86_64 GNU/Linux > > $mdadm --version > mdadm - v4.2 - 2021-12-30 > > $ sudo mdadm --detail /dev/md0 > /dev/md0: > Version : 1.2 > Raid Level : raid6 > Total Devices : 1 > Persistence : Superblock is persistent > > State : inactive > Working Devices : 1 > > Name : NAS-ubuntu:0 > UUID : 2bf6381b:fe19bdd4:9cc53ae7:5dce1630 > Events : 477468 > > Number Major Minor RaidDevice > - 8 32 - /dev/sdc > > > So what should I do next? > I have not run the --create --assume-clean yet but could that help in this case? > > Thanks for any help. > > Best regards, > Topi Viljanen >
