Hello,
We tried to do:
mdadm --grow /dev/md126 --raid-devices=4
and we get:
mdadm: Insufficient head-space for reshape on /dev/sda2
This is the present configuration:
# mdadm --misc --detail /dev/md126
/dev/md126:
Version : 1.0
Creation Time : Fri May 27 12:40:54 2016
Raid Level : raid10
Array Size : 512960 (500.94 MiB 525.27 MB)
Used Dev Size : 512960 (500.94 MiB 525.27 MB)
Raid Devices : 2
Total Devices : 4
Persistence : Superblock is persistent
Update Time : Mon Aug 3 17:33:04 2020
State : clean
Active Devices : 2
Working Devices : 4
Failed Devices : 0
Spare Devices : 2
Layout : near=2
Chunk Size : 64K
Consistency Policy : resync
Name : boot
UUID : 5fc23b3c:93ecd502:0fbf3b82:adc7ad2d
Events : 746
Number Major Minor RaidDevice State
0 8 2 0 active sync set-A /dev/sda2
4 8 50 1 active sync set-B /dev/sdd2
2 8 18 - spare /dev/sdb2
3 8 34 - spare /dev/sdc2
# cat /etc/mdadm.conf
ARRAY /dev/md/boot_0 metadata=1.0 spares=2 name=boot UUID=5fc23b3c:93ecd502:0fbf3b82:adc7ad2d
# cat /proc/mdstat
Personalities : [raid1] [raid10] [raid0]
md126 : active raid10 sdd2[4] sdc2[3](S) sdb2[2](S) sda2[0]
512960 blocks super 1.0 2 near-copies [2/2] [UU]
# fdisk /dev/sda
The device presents a logical sector size that is smaller than
the physical sector size. Aligning to a physical sector (or optimal
I/O) size boundary is recommended, or performance may be impacted.
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Orden (m para obtener ayuda): p
Disk /dev/sda: 500.1 GB, 500107862016 bytes, 976773168 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
Disk label type: dos
Identificador del disco: 0x0005ff1f
Disposit. Inicio Comienzo Fin Bloques Id Sistema
/dev/sda1 2048 8265727 4131840 8e Linux LVM
/dev/sda2 * 8265728 9291775 513024 fd Linux raid autodetect
/dev/sda3 9291776 974243839 482476032 fd Linux raid autodetect
# parted /dev/sda
GNU Parted 3.1
Usando /dev/sda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print free
Model: ATA Crucial_CT500MX2 (scsi)
Disk /dev/sda: 500GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos
Disk Flags:
Numero Inicio Fin Tamaño Typo Sistema de ficheros Banderas
32,3kB 1049kB 1016kB Free Space
1 1049kB 4232MB 4231MB primary lvm
2 4232MB 4757MB 525MB primary xfs arranque, raid
3 4757MB 499GB 494GB primary raid
499GB 500GB 1295MB Free Space
