how to copy raid5 array with smart array5i ?

[Rene Sasse]

Hi,

i wonder if it's possible to copy a complete raid5 array (build with 3 HD) to another array within the same hardware. Hardware: ProLiant DL380 with smart5i raid controller on board. OS: RedHat ES 3u3.

What i need is a exactly copy of the first running array.

Does any one have any idea?

regards,
rene

[Colin_29 · Accepted solution]

Just a thought but would RAID5+1 help?

[Vincent Fleming]

You could use RH's built-in software RAID1, or you can copy it via the "dd" command.

Do you have 2 3-drive RAID5s?

[Rene Sasse]

yes; i've got 2 3-drive RAID5... 1 with the running system, the other one waiting for copy. would you pls write a little step-by-step manual of how to copy the system via dd ? i've tried this last week but i failed :(

regards,
rene

[kcpant]

Hi Rene,

As colin said, you can try by putting your second empty 3disks to working DL380, make another raid 5 on this and mirror both raid volumes.

[Devender Khatana]

Hi,

Have u completed the configuration part for the second raid5 devive ? Is it appearing as a disk to your OS ? Is the first raids viloume is your OS disk? If it is appearing as a reparate disk to your OS then you can do a dd.

Take two devive files, ( For working raid 5 array and new raid 5 array)

Suppose if first (Working) disk is /dev/rd(or ida)/c0d0 and second is /dev/rd(or ida)/c0d1

Then do

dd if=/dev/rd(or ida)/c0d0 of=/dev/rd(or ida)/c0d1 bs=1024K

Another option is to sync first disk with your second disk. use default Linux raid options for that.

HTH,
Devender

[Devender Khatana]

Hi Rene,

Another suggestion.


What is the reason for changing disks in the raid5 volume?

Peroform and test backup before this.

Are these disks are of big size or something alse? If new disks are of same size you can also do it by dummy replacement also of all three disks. i.e. remove one disk from the array put in new disk,sync it and then replace another disk and so on.

HTH,
Devender