Hello Linux-Raid-ers,
I've never reached out to a kernel list before so go easy on me.
I'm attempting to resize a Raid6 array from 5 drives to 4 drives. The
5th drive has been removed from the system and the RAID is clean. I've
resized the filesystem to 4500G from ~8700G. Now I'm attempting to
shrink the array size before I grow the array down to 4 drives from 5
but I'm getting the following issue, MDADM says there is not enough
space on the device to shrink the array size down. I'm not sure what
I'm missing here, does anyone have suggestions?
#####
root@helios4:/# e2fsck -f /dev/md0
e2fsck 1.43.4 (31-Jan-2017)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
Manta_Array: 486515/8584448 files (1.2% non-contiguous),
1021950160/2197600128 blocks
root@helios4:/#
root@helios4:/# resize2fs /dev/md0 4500G
resize2fs 1.43.4 (31-Jan-2017)
Resizing the filesystem on /dev/md0 to 1179648000 (4k) blocks.
The filesystem on /dev/md0 is now 1179648000 (4k) blocks long.
root@helios4:/#
root@helios4:/# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4] [raid0] [raid1] [raid10]
md0 : active raid6 sdc1[1] sdd1[6] sdb1[5] sda1[8]
8790400512 blocks super 1.2 level 6, 512k chunk, algorithm 2 [5/4] [_UUUU]
unused devices: <none>
root@helios4:/# mdadm --grow /dev/md0 --size=5860267008
mdadm: Cannot set device size for /dev/md0: No space left on device
#######
Other Possibly Relevant Information:
root@helios4:/# mdadm -Q -D /dev/md0
/dev/md0:
Version : 1.2
Creation Time : Fri Apr 26 02:45:32 2013
Raid Level : raid6
Array Size : 8790400512 (8383.18 GiB 9001.37 GB)
Used Dev Size : 2930133504 (2794.39 GiB 3000.46 GB)
Raid Devices : 5
Total Devices : 4
Persistence : Superblock is persistent
Update Time : Sat Jan 19 07:17:20 2019
State : clean, degraded
Active Devices : 4
Working Devices : 4
Failed Devices : 0
Spare Devices : 0
Layout : left-symmetric
Chunk Size : 512K
Name : blackbox:0
UUID : f6ff12cd:86a8e3fb:89bc0f58:ad15e3e2
Events : 1846412
Number Major Minor RaidDevice State
- 0 0 0 removed
1 8 33 1 active sync /dev/sdc1
8 8 1 2 active sync /dev/sda1
5 8 17 3 active sync /dev/sdb1
6 8 49 4 active sync /dev/sdd1
root@helios4:/home/eric# mdadm --version
mdadm - v3.4 - 28th January 2016
root@helios4:/home/eric# uname -a
Linux helios4 4.14.83-mvebu #520 SMP Mon Nov 26 09:28:27 CET 2018
armv7l GNU/Linux
root@helios4:/home/eric# cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux 9 (stretch)"
NAME="Debian GNU/Linux"
VERSION_ID="9"
VERSION="9 (stretch)"
ID=debian
