RE: Please help with a special RAID 1 setup

RE: Please help with a special RAID 1 setup

[linux]

Andy Cress wrote:
> Note that RAID-1 will only ever have a maximum of 2 active disks.
> When you add the 3rd disk, it is added to the array as a spare, that's
> why it doesn't rebuild.

That surprises the hell out of me...

> md1 : active raid1 hdk1[5] hdi1[4] hdg1[3] hde1[2] hdc1[1] hda1[0]
>      439360 blocks [6/6] [UUUUUU]

(/boot and backup recovery tools.)

Re: Please help with a special RAID 1 setup

[Mircea Ciocan]

Cress, Andrew R wrote:

>Well, the simplest thing would be to detach one of the mirror disks,
>keep it as the backup, then insert a new one for the resync.  Is that
>what you want?
>
>Andy
>  
>
    Well yes but I don't want to change phisically the wires, so I can 
detach a slice via sowtware, but new slice will be a different device ( 
on another controller), do you thing this is possible and how ( I try 
now to grok Luca's solution but not yet ready).

    Mircea

Re: Please help with a special RAID 1 setup

[Mircea Ciocan]

Rechenberg, Andrew wrote:

> 
>
>  
>
>>-----Original Message-----
>>From: linux-raid-owner@vger.kernel.org 
>>[mailto:linux-raid-owner@vger.kernel.org] On Behalf Of Cress, Andrew R
>>Sent: Wednesday, January 07, 2004 9:48 AM
>>To: Catalin BOIE; Mircea Ciocan
>>Cc: linux-raid@vger.kernel.org
>>Subject: RE: Please help with a special RAID 1 setup
>>
>>
>>Note that RAID-1 will only ever have a maximum of 2 active disks.
>>    
>>
>
>I don't believe that the above is a correct statement.  Linux software
>RAID1 will allow mirroring across more than 2 devices:
>
>[root@cinshrlnxlap01 ~]# cat /proc/mdstat
>Personalities : [raid1]
>read_ahead 1024 sectors
>md2 : active raid1 [dev 01:02][2] [dev 01:01][1] [dev 01:00][0]
>      4032 blocks [3/3] [UUU]
>
>  
>
    This is a refershing info, depressing is the fact that a slice can't 
be added unobrtusively ( sp ?), I'll try Luca's solution first than 
scratch & rebuild if this will be a resounding failure  ;).

[SNIP]

>We had a "triple" mirror sofware RAID setup on a box as a "poor man's
>snapshot" before we started using LVM.  We triple mirrored and then
>broke one mirror to backup and then added the removed disk back into the
>array and re-synched.  LVM snapshots are much more elegant and LVM
>provides more functionality such as extended volumes when you want to
>add more space.  You have to be careful using LVM because as of 2.4.18
>there was a Linux VM bug that would not allow snapshotting with greater
>than about 6GB of system RAM.
>
>However, I would recommend recreating the filesystem on top of LVM and
>using snapshots to accomplish what you want.  We use LVM on top of SW
>RAID with great success.
>
>  
>
    Ha, so I'm not the only one crazy enough to propose such a solution, 
I'm happy that I'm not alone :),  did it worked ??
I belive that was designed and initialised from the first time as a 3 
slice raid, the 3rd slice wasn't aded as an aftertought ??

The raid boxes have 4GiB RAM so is not a problem, BTW to you have a 
pointer for starting the RTFM about that LVM and especially those 
snapshots, is there a posibility to to save the inital setup with 2 
slices or everything has to be destroyed and recreated again???

    Best regards,

    Mircea

RE: Please help with a special RAID 1 setup

[Cress, Andrew R]

Well, the simplest thing would be to detach one of the mirror disks,
keep it as the backup, then insert a new one for the resync.  Is that
what you want?

Andy

-----Original Message-----
From: Mircea Ciocan [mailto:mirceac@interplus.ro] 
Sent: Wednesday, January 07, 2004 10:34 AM
To: Cress, Andrew R
Cc: Catalin BOIE; linux-raid@vger.kernel.org
Subject: Re: Please help with a special RAID 1 setup


Cress, Andrew R wrote:

>Note that RAID-1 will only ever have a maximum of 2 active disks.
>When you add the 3rd disk, it is added to the array as a spare, that's
>why it doesn't rebuild.
>
>Andy
>  
>
    Ouch, so is there really no posibility to obtain somehow what I 
explained in the previous mail ( a cvasi-realtime filesystem backup by 
attaching and detaching a device) :(((
Please tell me that there is a posibility, my world is shattered ;)
 
       Mircea

RE: Please help with a special RAID 1 setup

[Michael]

<snip> 
> I don't believe that the above is a correct statement.  Linux
> software RAID1 will allow mirroring across more than 2 devices:
>

This is correct. Below is info and conf file from our raid1 setup

Boot sector (md1) is 3 partition raid 1
swap and root are 2 partition raid 1 with hot spare

Personalities : [raid0] [raid1] [raid5] 
read_ahead 1024 sectors
md1 : active raid1 sdc1[2] sdb1[1] sda1[0]
      15936 blocks [3/3] [UUU]

md2 : active raid1 sdc2[2] sdb2[1] sda2[0]
      489856 blocks [2/2] [UU]

md0 : active raid1 sdc3[2] sdb3[1] sda3[0]
      16924352 blocks [2/2] [UU]


# raid-1 configuration
raiddev /dev/md1
        raid-level              1
        nr-raid-disks           3
        chunk-size              4
# Spare disks for hot reconstruction
        nr-spare-disks          0
        persistent-superblock   1
        device                  /dev/sda1
        raid-disk               0
        device                  /dev/sdb1
        raid-disk               1
        device                  /dev/sdc1
        raid-disk               2

raiddev /dev/md0
        raid-level              1
        nr-raid-disks           2
        chunk-size              32
        nr-spare-disks          1
        persistent-superblock   1
        device                  /dev/sda3
        raid-disk               0
        device                  /dev/sdb3
        raid-disk               1
        device                  /dev/sdc3
        spare-disk              0

raiddev /dev/md2
        raid-level              1
        nr-raid-disks           2
        chunk-size              4
# Spare disks for hot reconstruction
        nr-spare-disks          1
        persistent-superblock   1
        device                  /dev/sda2
        raid-disk               0
        device                  /dev/sdb2
        raid-disk               1
        device                  /dev/sdc2
        spare-disk              0

Michael@Insulin-Pumpers.org

RE: Please help with a special RAID 1 setup

[Rechenberg, Andrew]

 

> -----Original Message-----
> From: linux-raid-owner@vger.kernel.org 
> [mailto:linux-raid-owner@vger.kernel.org] On Behalf Of Cress, Andrew R
> Sent: Wednesday, January 07, 2004 9:48 AM
> To: Catalin BOIE; Mircea Ciocan
> Cc: linux-raid@vger.kernel.org
> Subject: RE: Please help with a special RAID 1 setup
> 
> 
> Note that RAID-1 will only ever have a maximum of 2 active disks.

I don't believe that the above is a correct statement.  Linux software
RAID1 will allow mirroring across more than 2 devices:

[root@cinshrlnxlap01 ~]# cat /proc/mdstat
Personalities : [raid1]
read_ahead 1024 sectors
md2 : active raid1 [dev 01:02][2] [dev 01:01][1] [dev 01:00][0]
      4032 blocks [3/3] [UUU]

unused devices: <none>

[root@cinshrlnxlap01 ~]# mount /dev/md2 /mnt/cdrom/
[root@cinshrlnxlap01 ~]# cd /mnt/cdrom/
[root@cinshrlnxlap01 /mnt/cdrom]# dir
total 17
drwxr-xr-x    3 root     root         1024 Jan  7 12:09 .
drwxr-xr-x    4 root     root         4096 Dec 30 07:46 ..
drwx------    2 root     root        12288 Jan  7 12:09 lost+found

[root@cinshrlnxlap01 /mnt/cdrom]# touch hithere
[root@cinshrlnxlap01 /mnt]# umount cdrom/
[root@cinshrlnxlap01 /mnt]# raidstop /dev/md2
[root@cinshrlnxlap01 /mnt]# mount /dev/ram0 /mnt/cdrom/
[root@cinshrlnxlap01 /mnt]# ls -la cdrom/
total 17
drwxr-xr-x    3 root     root         1024 Jan  7 12:10 .
drwxr-xr-x    4 root     root         4096 Dec 30 07:46 ..
-rw-r--r--    1 root     root            0 Jan  7 12:10 hithere
drwx------    2 root     root        12288 Jan  7 12:09 lost+found
[root@cinshrlnxlap01 /mnt]# umount cdrom/
umount: /mnt/cdrom: device is busy
[root@cinshrlnxlap01 /mnt]# umount cdrom/
[root@cinshrlnxlap01 /mnt]# mount /dev/ram1 /mnt/cdrom/
[root@cinshrlnxlap01 /mnt]# ls -la cdrom/
total 17
drwxr-xr-x    3 root     root         1024 Jan  7 12:10 .
drwxr-xr-x    4 root     root         4096 Dec 30 07:46 ..
-rw-r--r--    1 root     root            0 Jan  7 12:10 hithere
drwx------    2 root     root        12288 Jan  7 12:09 lost+found
[root@cinshrlnxlap01 /mnt]# umount cdrom/
[root@cinshrlnxlap01 /mnt]# mount /dev/ram2 /mnt/cdrom/
[root@cinshrlnxlap01 /mnt]# ls -la /mnt/cdrom/
total 17
drwxr-xr-x    3 root     root         1024 Jan  7 12:10 .
drwxr-xr-x    4 root     root         4096 Dec 30 07:46 ..
-rw-r--r--    1 root     root            0 Jan  7 12:10 hithere
drwx------    2 root     root        12288 Jan  7 12:09 lost+found 

We had a "triple" mirror sofware RAID setup on a box as a "poor man's
snapshot" before we started using LVM.  We triple mirrored and then
broke one mirror to backup and then added the removed disk back into the
array and re-synched.  LVM snapshots are much more elegant and LVM
provides more functionality such as extended volumes when you want to
add more space.  You have to be careful using LVM because as of 2.4.18
there was a Linux VM bug that would not allow snapshotting with greater
than about 6GB of system RAM.

However, I would recommend recreating the filesystem on top of LVM and
using snapshots to accomplish what you want.  We use LVM on top of SW
RAID with great success.


> When you add the 3rd disk, it is added to the array as a 
> spare, that's why it doesn't rebuild.
> 
> Andy
> 
> -----Original Message-----
> From: linux-raid-owner@vger.kernel.org
> [mailto:linux-raid-owner@vger.kernel.org] On Behalf Of Catalin BOIE
> Sent: Wednesday, January 07, 2004 8:48 AM
> To: Mircea Ciocan
> Cc: linux-raid@vger.kernel.org
> Subject: Re: Please help with a special RAID 1 setup
> 
> 
> > >I think that you must replace:
> > >	nr-raid-disks   2
> > >with
> > >	nr-raid-disks   3
> > >Plus, the correspinding entry:
> > >	device          /dev/sdb3
> > >	raid-disk       2
> > >
> > >Else, the third drive isn't recognized as part of the md array.
> > >Probably, you must restart the array (only first time).
> > >You may want to use mdadm instead of raidtools.
> > >
> > >
> > >
> >
> >     Modified config file, umounted and stoped raid, restarted raid, 
> > hotadded the disk, still the same results :(.
> > Any other ideeas ??
> >
> >     Mircea
> 
> I think you must rebuid the /dec/md0 with mkraid --upgrade.
> Warning! You may destroy all data, so backup first.
> 
> ---
> Catalin(ux) BOIE
> catab@deuroconsult.ro
> -
> 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
> -
> To unsubscribe from this list: send the line "unsubscribe 
> linux-raid" in the body of a message to 
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> http://vger.kernel.org/majordomo-info.html
> 
> 

Re: Please help with a special RAID 1 setup

[Luca Berra]

Mircea Ciocan wrote:
>    Ouch, so is there really no posibility to obtain somehow what I 
> explained in the previous mail ( a cvasi-realtime filesystem backup by 
> attaching and detaching a device) :(((
> Please tell me that there is a posibility, my world is shattered ;)
> 
use mdadm and recreate the array with 3 devices (using the missing 
keyword in place of the 3rd drive), then hotadd the new disk.

this operation does not destroy your data, but be sure to test it on a 
spare server until you are confident with the syntax

regards,
L.

Re: Please help with a special RAID 1 setup

[Mircea Ciocan]

Cress, Andrew R wrote:

>Note that RAID-1 will only ever have a maximum of 2 active disks.
>When you add the 3rd disk, it is added to the array as a spare, that's
>why it doesn't rebuild.
>
>Andy
>  
>
    Ouch, so is there really no posibility to obtain somehow what I 
explained in the previous mail ( a cvasi-realtime filesystem backup by 
attaching and detaching a device) :(((
Please tell me that there is a posibility, my world is shattered ;)
 
       Mircea

Re: Please help with a special RAID 1 setup

[Dr. Greg Wettstein]

On Jan 7, 12:16pm, Mircea Ciocan wrote:
} Subject: Please help with a special RAID 1 setup

>     Hello all,

Good morning to everyone on the list(s).

>     First excuse me for a looong message, but I've tryed to give as much 
> relevant details as possible.
> 
>     Please help me with this weird setup if it is possible and fesable:
> 
>     I have this raid1 device, composed of two fibre channel devices 
> mounted in RAID1, it works absolutely flawlessly.
> The resulted device is used for a lot of important data logging and the 
> ideea is to hotattach a 3-rd device ot the same size, wait for 
> syncronisation and after all of them are syncronised, stop the data 
> logging process, wait for a while, issue a sync command and hot detach 
> the 3-rd device restart de data logging and walk away with valid 
> filesytem backup of the main arry to be used as separate data analysys 
> source. I know that solution is somewhat cumberome but trust me this is 
> needed as is.

I know that it adds complexity but it would seem that this solution
would benefit from using LVM with its snap-shotting capabilities.

If you need to walk away with the data, snap the filesystem, copy the
snap to a separate device/filesystem, release the snap and you are
done.  I believe that there is a utility floating around that will
force synchronization of the filesystem (ext[23]) if your desire is to
have a coherent filesystem image as well.

I suspect that in the long run you will have a more coherent log image
with less muss and fuss.

>        Mircea Ciocan

Good luck with the project.

}-- End of excerpt from Mircea Ciocan

As always,
Dr. G.W. Wettstein, Ph.D.   Enjellic Systems Development, LLC.
4206 N. 19th Ave.           Specializing in information infra-structure
Fargo, ND  58102            development.
PH: 701-281-1686
FAX: 701-281-3949           EMAIL: greg@enjellic.com
------------------------------------------------------------------------------
"Given a choice between a complex, difficult-to-understand,
disconcerting explanation and a simplistic, comforting one, many
prefer simplistic comfort if it's remotely plausible, especially if it
involves blaming someone else for their problems."
                                -- Bob Lewis
                                   _Infoworld_

RE: Please help with a special RAID 1 setup

[Cress, Andrew R]

Note that RAID-1 will only ever have a maximum of 2 active disks.
When you add the 3rd disk, it is added to the array as a spare, that's
why it doesn't rebuild.

Andy

-----Original Message-----
From: linux-raid-owner@vger.kernel.org
[mailto:linux-raid-owner@vger.kernel.org] On Behalf Of Catalin BOIE
Sent: Wednesday, January 07, 2004 8:48 AM
To: Mircea Ciocan
Cc: linux-raid@vger.kernel.org
Subject: Re: Please help with a special RAID 1 setup


> >I think that you must replace:
> >	nr-raid-disks   2
> >with
> >	nr-raid-disks   3
> >Plus, the correspinding entry:
> >	device          /dev/sdb3
> >	raid-disk       2
> >
> >Else, the third drive isn't recognized as part of the md array.
> >Probably, you must restart the array (only first time).
> >You may want to use mdadm instead of raidtools.
> >
> >
> >
>
>     Modified config file, umounted and stoped raid, restarted raid,
> hotadded the disk, still the same results :(.
> Any other ideeas ??
>
>     Mircea

I think you must rebuid the /dec/md0 with mkraid --upgrade.
Warning! You may destroy all data, so backup first.

---
Catalin(ux) BOIE
catab@deuroconsult.ro
-
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

Re: Please help with a special RAID 1 setup

[Catalin BOIE]

> >I think that you must replace:
> >	nr-raid-disks   2
> >with
> >	nr-raid-disks   3
> >Plus, the correspinding entry:
> >	device          /dev/sdb3
> >	raid-disk       2
> >
> >Else, the third drive isn't recognized as part of the md array.
> >Probably, you must restart the array (only first time).
> >You may want to use mdadm instead of raidtools.
> >
> >
> >
>
>     Modified config file, umounted and stoped raid, restarted raid,
> hotadded the disk, still the same results :(.
> Any other ideeas ??
>
>     Mircea

I think you must rebuid the /dec/md0 with mkraid --upgrade.
Warning! You may destroy all data, so backup first.

---
Catalin(ux) BOIE
catab@deuroconsult.ro

Re: Please help with a special RAID 1 setup

[Catalin BOIE]

>     Modified config file, umounted and stoped raid, restarted raid,
> hotadded the disk, still the same results :(.
> Any other ideeas ??
>
>     Mircea

Can you give us the logs?

---
Catalin(ux) BOIE
catab@deuroconsult.ro

Re: Please help with a special RAID 1 setup

[Mircea Ciocan]

Catalin BOIE wrote:

>>    Here are some relevant data of the test setup that may be usefull:
>>[root@test]# cat /etc/raidtab
>>raiddev /dev/md0
>>raid-level      1
>>nr-raid-disks   2
>>nr-spare-disks  0
>>chunk-size     4
>>persistent-superblock 1
>>device          /dev/sda2
>>raid-disk       0
>>device          /dev/sdb2
>>raid-disk       1
>>    
>>
>
>I think that you must replace:
>	nr-raid-disks   2
>with
>	nr-raid-disks   3
>Plus, the correspinding entry:
>	device          /dev/sdb3
>	raid-disk       2
>
>Else, the third drive isn't recognized as part of the md array.
>Probably, you must restart the array (only first time).
>You may want to use mdadm instead of raidtools.
>
>  
>

    Modified config file, umounted and stoped raid, restarted raid, 
hotadded the disk, still the same results :(.
Any other ideeas ??

    Mircea

Re: Please help with a special RAID 1 setup

[Catalin BOIE]

>     Here are some relevant data of the test setup that may be usefull:
> [root@test]# cat /etc/raidtab
> raiddev /dev/md0
> raid-level      1
> nr-raid-disks   2
> nr-spare-disks  0
> chunk-size     4
> persistent-superblock 1
> device          /dev/sda2
> raid-disk       0
> device          /dev/sdb2
> raid-disk       1

I think that you must replace:
	nr-raid-disks   2
with
	nr-raid-disks   3
Plus, the correspinding entry:
	device          /dev/sdb3
	raid-disk       2

Else, the third drive isn't recognized as part of the md array.
Probably, you must restart the array (only first time).
You may want to use mdadm instead of raidtools.

> /proc/mdstat BEFORE adding the 3-rd device:
> [root@test]# cat /proc/mdstat
> Personalities : [raid1]
> read_ahead 1024 sectors
> md0 : active raid1 scsi/host3/bus0/target0/lun0/part2[1]
> scsi/host2/bus0/target0/lun0/part2[0]
>       710938560 blocks [2/2] [UU]
>
> unused devices: <none>
>
> Then I add the 3-rd device:
> [root@test]# raidhotadd /dev/md0 /dev/sdb3
>
> /proc/mdstat AFTER adding 3-rd device
>
> [root@nfs10 root]# cat /proc/mdstat
> Personalities : [raid1]
> read_ahead 1024 sectors
> md0 : active raid1 scsi/host3/bus0/target0/lun0/part3[2]
> scsi/host3/bus0/target0/lun0/part2[1] scsi/host2/bus0/target0/lun0/part2[0]
>       710938560 blocks [2/2] [UU]
>
> unused devices: <none>
>
> Piece of the syslog showing the add results:
> .....
> Jan  7 12:09:01 nfs10 kernel: md: updating md0 RAID superblock on device
> Jan  7 12:09:01 nfs10 kernel: md: scsi/host3/bus0/target0/lun0/part3
> [events: 00000012]<6>(write) scsi/host3/bus0/target0/lun0/part3's sb
> offset: 725598144
> Jan  7 12:09:01 nfs10 kernel: md: scsi/host3/bus0/target0/lun0/part2
> [events: 00000012]<6>(write) scsi/host3/bus0/target0/lun0/part2's sb
> offset: 710938560
> Jan  7 12:09:01 nfs10 kernel: md: scsi/host2/bus0/target0/lun0/part2
> [events: 00000012]<6>(write) scsi/host2/bus0/target0/lun0/part2's sb
> offset: 710938560
> ......
>
>     The problem is that no sync is done, as a matter of fact the 3rd
> disk is not even scrached visibly ;(, did I miss someting obvious or
> what I want is impossible ???
>
>     Thank you for reading such a long mail and for any help that will
> lead me solving this,
>
>        Mircea Ciocan
>
>
>
>
>
>
>
>
>
> -
> 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
>

---
Catalin(ux) BOIE
catab@deuroconsult.ro

Please help with a special RAID 1 setup

[Mircea Ciocan]

    Hello all,
    First excuse me for a looong message, but I've tryed to give as much 
relevant details as possible.

    Please help me with this weird setup if it is possible and fesable:

    I have this raid1 device, composed of two fibre channel devices 
mounted in RAID1, it works absolutely flawlessly.
The resulted device is used for a lot of important data logging and the 
ideea is to hotattach a 3-rd device ot the same size, wait for 
syncronisation and after all of them are syncronised, stop the data 
logging process, wait for a while, issue a sync command and hot detach 
the 3-rd device restart de data logging and walk away with valid 
filesytem backup of the main arry to be used as separate data analysys 
source. I know that solution is somewhat cumberome but trust me this is 
needed as is.
     Now if you read untill here I managed to hot-attach, the attaching 
was mentioned in the syslogfile, the data logging process continued 
undisturbed, even the cat /proc/mdstat showed the new device added BUT 
it only showed the same two   [2/2] [UU] and it didn't touch the 3-rd 
disk at all, also hotremoving was sucessful.

    Here are some relevant data of the test setup that may be usefull:
[root@test]# cat /etc/raidtab
raiddev /dev/md0
raid-level      1
nr-raid-disks   2
nr-spare-disks  0
chunk-size     4
persistent-superblock 1
device          /dev/sda2
raid-disk       0
device          /dev/sdb2
raid-disk       1

/proc/mdstat BEFORE adding the 3-rd device:
[root@test]# cat /proc/mdstat
Personalities : [raid1]
read_ahead 1024 sectors
md0 : active raid1 scsi/host3/bus0/target0/lun0/part2[1] 
scsi/host2/bus0/target0/lun0/part2[0]
      710938560 blocks [2/2] [UU]

unused devices: <none>

Then I add the 3-rd device:
[root@test]# raidhotadd /dev/md0 /dev/sdb3

/proc/mdstat AFTER adding 3-rd device

[root@nfs10 root]# cat /proc/mdstat
Personalities : [raid1]
read_ahead 1024 sectors
md0 : active raid1 scsi/host3/bus0/target0/lun0/part3[2] 
scsi/host3/bus0/target0/lun0/part2[1] scsi/host2/bus0/target0/lun0/part2[0]
      710938560 blocks [2/2] [UU]

unused devices: <none>

Piece of the syslog showing the add results:
.....
Jan  7 12:09:01 nfs10 kernel: md: updating md0 RAID superblock on device
Jan  7 12:09:01 nfs10 kernel: md: scsi/host3/bus0/target0/lun0/part3 
[events: 00000012]<6>(write) scsi/host3/bus0/target0/lun0/part3's sb 
offset: 725598144
Jan  7 12:09:01 nfs10 kernel: md: scsi/host3/bus0/target0/lun0/part2 
[events: 00000012]<6>(write) scsi/host3/bus0/target0/lun0/part2's sb 
offset: 710938560
Jan  7 12:09:01 nfs10 kernel: md: scsi/host2/bus0/target0/lun0/part2 
[events: 00000012]<6>(write) scsi/host2/bus0/target0/lun0/part2's sb 
offset: 710938560
......

    The problem is that no sync is done, as a matter of fact the 3rd 
disk is not even scrached visibly ;(, did I miss someting obvious or 
what I want is impossible ???

    Thank you for reading such a long mail and for any help that will 
lead me solving this,

       Mircea Ciocan