MD devices renaming or re-ordering question

[Maurice Hilarius <maurice@harddata.com>]

Hi to all.

I wonder if somebody would care to help me to solve a problem?

I have some servers.
They are running CentOS5
This OS has a limitation where the maximum filesystem size is 8TB.

Each server curr3ently has a  AMCC/3WARE 16 port SATA controllers. Total
of 16 ports / drives
I am using 750GB drives.

I am exporting the drives as single, NOT as hardware RAID
That is due to the filesystem and controller limitations, among other
reasons.

Each server currently has 16 disks attached to the one controller

I want to add a 2nd controller, and, for now, 4 more disks on it.

I want to have the boot disk as a plain disk, as presently configured as
sda1,2,3

The remaining 15 disks are configured as :
sdb1 through sde1 as md0 ( 4 devices/partitions)
sdf1 through sdp1 as md1 (10 devices/partitions)
I want to add a 2nd controller, and 4 more drives, to the md0 device.

But, I do not want md0 to be "split" across the 2 controllers this way.
I prefer to do the split on md1

Other than starting from scratch, the best solution would be to add the
disks to md0, then to "magically" turn md0 into md1, and md1 into md0

So, the question:
How does one make md1 into md0, and vice versa?
Without losing the data on these md's ?

Thanks in advance for any suggestions.



-- 
Regards, Maurice


/09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0/

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