mdadm: hot add failed ... lun0/part6: No space left on device

mdadm: hot add failed ... lun0/part6: No space left on device

[Sandro Dentella]

Hi all,
  while trying to substitute a failed disk, I'm using the command:  

    # mdadm /dev/md1 --add /dev/ide/host0/bus1/target0/lun0/part6

  but I get:

  mdadm: hot add failed for /dev/ide/host0/bus1/target0/lun0/part6: No space left on device

  What does it mean?

  I don't know how to interpret it. I thought it was the partition that
  is not same dime as the other one (disks are different) but the partition
  I'm adding is bigger... as you can see further on.

  I noticed that the 2 disks are not seen in the same way, as if the second
  is not in LBA mode:

	cat /proc/ide/hda/model
	MODEL: MAXTOR 6L040J2
	GEOMETRY:
	cat /proc/ide/hda/geometry
	physical     77557/16/63
	logical      4866/255/63

	cat /proc/ide/hdc/model
	MODEL: Maxtor 6E040L0
	GEOMETRY:
	cat /proc/ide/hdc/geometry
	physical     79656/16/63
	logical      79656/16/63

###########  mdstat ##########################################################
    root@argo-cd root # cat /proc/mdstat 
    Personalities : [raid1] 
    read_ahead 1024 sectors
    md0 : active raid1 hdc1[1] ide/host0/bus0/target0/lun0/part1[0]
	  24000 blocks [2/2] [UU]

    md1 : active raid1 ide/host0/bus0/target0/lun0/part6[0]
	  2048192 blocks [2/1] [U_]

    md2 : active raid1 ide/host0/bus0/target0/lun0/part7[0]
	  36491520 blocks [2/1] [U_]

    unused devices: <none>


###########  fdisk - parted ##################################################
    And here are the partition tables of the disks:

root@argo-cd root # parted /dev/hda print
Disk geometry for /dev/ide/host0/bus0/target0/lun0/disc: 0.000-38172.750 megabytes
Disk label type: msdos
Minor    Start       End     Type      Filesystem  Flags
1          0.031     23.532  primary   ext2        raid
2         23.533  38170.063  extended              lba
5         23.563    533.408  logical   linux-swap  
6        533.439   2533.688  logical   reiserfs    raid
7       2533.720  38170.063  logical   reiserfs    raid



root@argo-cd root # parted /dev/hdc print
Disk geometry for /dev/ide/host0/bus1/target0/lun0/disc: 0.000-39205.687 megabytes
Disk label type: msdos
Minor    Start       End     Type      Filesystem  Flags
1          0.031     23.625  primary   ext2        raid
2         23.625  39205.687  extended              lba
5         23.656    533.531  logical               
6        533.562   2536.242  logical               raid
7       2536.273  39205.687  logical               raid

Thanks in advance
sandro
*:-)


-- 
Sandro Dentella  *:-)
e-mail: sandro.dentella@tin.it 
http://www.tksql.org                    TkSQL Home page - My GPL work

Re: mdadm: hot add failed ... lun0/part6: No space left on device

[Neil Brown]

On Friday January 30, sandro.dentella@tin.it wrote:
> Hi all,
>   while trying to substitute a failed disk, I'm using the command:  
> 
>     # mdadm /dev/md1 --add /dev/ide/host0/bus1/target0/lun0/part6
> 
>   but I get:
> 
>   mdadm: hot add failed for /dev/ide/host0/bus1/target0/lun0/part6: No space left on device
> 
>   What does it mean?

It means, as you guess lower down, that the partition you have
provided appears to be too small to be used in the given array.

This error should cause a message to appear in the kernel logs
something like

   md1: disk size XXX blocks < array size YYY

You might finding it by
   dmesg | grep 'disk size'

or looking in some file in /var/log (depending on which distribution
you use.  Debian puts it in /var/log/kern.log).

> 
>   I don't know how to interpret it. I thought it was the partition that
>   is not same dime as the other one (disks are different) but the partition
>   I'm adding is bigger... as you can see further on.

Indeed I can:  hda6 appears to be 2533.688 - 533.439 = 2000.249 Mb
while hdc6 (the new one) is 2536.242 - 533.562 = 2002.680 Mb

My only guess is that the kernel hasn't found out about some recent
change in partition size.  What partition sizes are given in
   cat /proc/partitions
??

NeilBrown

Re: mdadm: hot add failed ... lun0/part6: No space left on device

[Sandro Dentella]

On Sat, Jan 31, 2004 at 09:41:27PM +1100, Neil Brown wrote:
> >     # mdadm /dev/md1 --add /dev/ide/host0/bus1/target0/lun0/part6
> > 
> >   but I get:
> > 
> >   mdadm: hot add failed for /dev/ide/host0/bus1/target0/lun0/part6: No space left on device
> It means, as you guess lower down, that the partition you have
> provided appears to be too small to be used in the given array.
> 
> This error should cause a message to appear in the kernel logs
> something like
> 
>    md1: disk size XXX blocks < array size YYY
> 
> You might finding it by
>    dmesg | grep 'disk size'
> 
> or looking in some file in /var/log (depending on which distribution
> you use.  Debian puts it in /var/log/kern.log).

It's a pity the system was running on a rescue CD so when I had to reboot
(the client really needed to have it up soon) I lost the messages. I can
tell that I bypassed the problem swapping the position of the two HD (hda
and hdc). At that point both where seen in LBA mode and the partition could
be added... I that any usefull to help understand? Is there anything I
could/should have been done to avoid this behaviour?

Why hdc is so often seen not in LBA mode (BIOS set up correctly) until you
force it w/ fdisk while hda is always right?

Thanks for your help

sandro
*:-)

-- 
Sandro Dentella  *:-)
e-mail: sandro.dentella@tin.it 
http://www.tksql.org                    TkSQL Home page - My GPL work