How to copy/clone a disk on T2000 with Solaris 10

Ben99 · 05-04-2011, 12:45 PM

Hi, on my T2000, there are currently two disks, no RAID. OS is installed on c0t0d0.

On c0t1d0, there is only one partition, and this disk is mounted under /zones.

Given that I never done this before, could someone offer step by step guide to copy c0t1d0 to c0t3d0?

c0t3d0 is a brand new disk of the same capacity. Thanks.

zordrak · 05-04-2011, 12:51 PM

Not necessarily the most efficient but certainly one of the most effective ways:

% dd if=/dev/rdsk/c0t1d0s2 of=/dev/rdsk/c0t3d0s2 bs=128

(Bearing in mind that slice 2 is actually a representation of the whole disk - stupid but true).

Ben99 · 05-04-2011, 01:23 PM

do you need to shutdown OS to do this?
what about other slices?

zordrak · 05-04-2011, 01:39 PM

Quote:

Originally Posted by Ben99

do you need to shutdown OS to do this?

No, 'cos it's not your OS disk.

Quote:

Originally Posted by Ben99

what about other slices?

That's what I meant about the representation of the whole disk.

Slice 2 isn't a real partition, it's how you access the whole raw disk. Saying c0t1d0s2 is just like saying c0t1d0, but tools won't work on the disk as a whole without a slice numbers, so Solaris works by using slice 2 to mean "the whole disk". That's why slice 2 is always the same size as the disk itself.

Ben99 · 05-04-2011, 01:42 PM

zordrak:

Thank you much. I will post the results after I execute that command.

jlliagre · 05-04-2011, 02:24 PM

Quote:

Originally Posted by zordrak

Not necessarily the most efficient but certainly one of the most effective ways:

% dd if=/dev/rdsk/c0t1d0s2 of=/dev/rdsk/c0t3d0s2 bs=128

That would be extremely slow. I would recommend something like bs=128k if you don't wan't the copy to take hours, if not days.

Quote:

(Bearing in mind that slice 2 is actually a representation of the whole disk - stupid but true).

That's an historical convention from the Solaris BSD legacy. Note that this doesn't apply on x86 architecture, but it's okay with a T2000 (SPARC).

jlliagre · 05-04-2011, 02:29 PM

Quote:

Originally Posted by Ben99

do you need to shutdown OS to do this?

No, but I would strongly advise to unmount all filesystems using the source disk.

Depending on how much of the disk space is used by actual data, an ufsdump/ufsrestore might be more efficient.

If you use ZFS and not UFS, the dd cloning method might fail.

Ben99 · 05-04-2011, 02:29 PM

here is what I got:

# dd if=/dev/rdsk/c0t1d0s2 of=/dev/rdsk/c0t3d0s2 bs=128
read: Invalid argument
0+0 records in
0+0 records out

any suggestions?

jlliagre · 05-04-2011, 03:48 PM

Code:

dd if=/dev/dsk/c0t1d0s2 of=/dev/dsk/c0t3d0s2 bs=128k

Ben99 · 05-05-2011, 12:14 AM

it took long time, then it failed.

Is it better to unmount the if and of target, then run the dd command?

jlliagre · 05-05-2011, 04:11 AM

Quote:

Originally Posted by Ben99

it took long time

How long ? What is the disk size ?

Quote:

then it failed.

What makes you feel it did ?

Quote:

Is it better to unmount the if and of target, then run the dd command?

I already wrote you need to unmount the source filesystems. Unmounting the target doesn't make sense as it can't be mounted yet anyway.

Ben99 · 05-05-2011, 09:05 AM

jlliagre,

Thanks for taking time to answer the questions. I am not that familiar with Solaris, but this T2000 was thrown to me

How can I tell if I have ZFS?

Given that I did not umount source disk, and some data has been written to target disk.
Can I format the target and start over?

The source disk contains just three zones.

jlliagre · 05-05-2011, 09:16 AM

Quote:

Originally Posted by Ben99

How can I tell if I have ZFS?

By running

Code:

zpool list
zpool status

Quote:

Given that I did not umount source disk, and some data has been written to target disk.
Can I format the target and start over?

There is no need to format the target disk in the first place.
Just turn off these three zones, unmount their filesystems and start over.

What is your disk size ?
How long did the first dd take ?
What makes you feel it failed ?

Ben99 · 05-05-2011, 09:38 AM

Quote:

What is your disk size ?

the disk size is 72GB

Quote:

How long did the first dd take ?

about 4 hours

Quote:

What makes you feel it failed ?

The console displayed various warnings and errors. I did not capture

jlliagre · 05-05-2011, 10:47 AM

Quote:

Originally Posted by Ben99

The console displayed various warnings and errors. I did not capture

Please keep and post them when you try again.