Re: mdadm doesn't wont to grow - help please

[NeilBrown <neilb@suse.de>]

[-- Attachment #1: Type: text/plain, Size: 3640 bytes --]

On Mon, 14 May 2012 15:49:53 +0200 Sergiusz Brzeziński
<Sergiusz.Brzezinski@supersystem.pl> wrote:

> Hi,
> 
> I would like to grow the RAID1.
> 
> - Raid1 size has about 50GB
> - two HD partition (sda2, sdb2) have about 80GB+ (each)
> 
> I do:
> 
> # mdadm --grow /dev/md0 --size=max
> 
> and I get the info, that the new size is 50GB. And I wonder: why not 80GB? The 
> size doesn't change! If I try to force size (--size=xxxxx), I get the message 
> that there is no space.
> 
> What did I wrong?

Probably used an ancient version of mdadm - more than a couple of months
old :-)

If you 
  for i in /sys/block/md0/md/dev*/size
  do echo 0 > $i
  done
then try again it might work better.

Newer mdadm (since May 2011) do this for you.

If you look at the "mdadm -E /dev/sda2" output before and after you will
notice that "Avail Dev Size" changes.

You can achieve the same effect by stopping the array, the assembling it
with --update=devicesize

  mdadm --stop /dev/md0
  mdadm --assemble /dev/md0 --update=devicesize /dev/sd[ab]2
  mdadm --grow /dev/md0 --size=max

NeilBrown


> 
> Bellow some facts about my configuration.
> 
> Please help.
> 
> Thank You in advance
> 
> Sergiusz Brzeziński
> -----------------------------------------------
> 
> # mdadm --detail /dev/md0
> 
> /dev/md0:
>          Version : 1.2
>    Creation Time : Wed Mar 30 07:25:47 2011
>       Raid Level : raid1
>       Array Size : 52427776 (50.00 GiB 53.69 GB)
>    Used Dev Size : 52427776 (50.00 GiB 53.69 GB)
>     Raid Devices : 2
>    Total Devices : 2
>      Persistence : Superblock is persistent
> 
>      Update Time : Mon May 14 09:16:16 2012
>            State : clean
>   Active Devices : 2
> Working Devices : 2
>   Failed Devices : 0
>    Spare Devices : 0
> 
>             Name : linux-uo1f.site:1
>             UUID : 603ab02b:f8e9c2b9:863ce780:7f8dfca7
>           Events : 5472151
> 
>      Number   Major   Minor   RaidDevice State
>         2       8        2        0      active sync   /dev/sda2
>         4       8       18        1      active sync   /dev/sdb2
> 
> 
> 
> # cat /proc/mdstat
> 
> Personalities : [raid1]
> md0 : active raid1 sda2[2] sdb2[4]
>        52427776 blocks super 1.2 [2/2] [UU]
> 
> unused devices: <none>
> 
> 
> # fdisk /dev/sdb
> 
> Disk /dev/sdb: 320.1 GB, 320072933376 bytes
> 255 heads, 63 sectors/track, 38913 cylinders, total 625142448 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
> Disk identifier: 0x0008f6dc
> 
>     Device Boot      Start         End      Blocks   Id  System
> /dev/sdb1   *        2048      208895      103424   83  Linux
> /dev/sdb2          208896   625142447   312466776   fd  Linux raid autodetect
> 
> 
> # fdisk /dev/sda
> 
> Disk /dev/sda: 90.0 GB, 90028302336 bytes
> 255 heads, 63 sectors/track, 10945 cylinders, total 175836528 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
> Disk identifier: 0x08e607c5
> 
>     Device Boot      Start         End      Blocks   Id  System
> /dev/sda1            2048      208895      103424   83  Linux
> /dev/sda2          208896   175836527    87813816   fd  Linux raid autodetect
> --
> To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 828 bytes --]