Cloning and DD

[Tim Stallman]

Hi,
I'm wanting to clone a disk using dd. I've done it in the past and it seems to work just fine. A colleague of mine recently brought up the point of disk geometry. He is saying I will need the exact kind of disk to do the cloning due to disk geometry being different. I was under the impression as long as my disk is greater than or equal to the disk being cloned it will work. Does anyone have any information on this subject?

Regards,
Tim

[Dietmar Konermann]

You are right with your assumption... geometry does not matter with modern SCSI disks.

Best regards...
Dietmar.

[Pete Randall]

Tim,

I remember something of the sort from several years ago when we were copying a root volume - they had to be identical (according to the HP S.E. we were working with). I don't know if that's still true or not because I've never tried doing it with non-identical disks.

Pete

[Eugeny Brychkov]

Tim, as soon as you have opposite opinions why not simply to try? I adree with Pete, I've heard the same some time ago. But as soon as Dietmar is HP, we should trust him.
But please be cautious if you want to connect cloned machine to the same network: cloning whole disk will leave network settings as original machine has. So to disable forcing of MAC address change and thus MAC address conflict you should inspect /etc/rc.config.d/hpetherconf and hpbase100conf files and remove MAC addresses from them (HP_ETHER_STATION_ADDRESS)
Eugeny

[Carlos Fernandez Riera]

I guess it will work, but nothing is for free..., as first step you will be lossing lots of disk space.

I noticed you are new in this forum, so try the search , use bolean, check the forum box and write some words mirror, dd. I've found several threads for these.

[Steve Labar]

If you dd to a disk that is larger and you are using vg, your clone will be setup with same specs as original. In other words, if you dd a 9GB disk to an 18GB disk, the 18GB disk will be setup with the 9GB parameters, losing 9GB with no way to get it back. Other than that, there shouldn't be a problem.

Good Luck.

Steve

[Frank Slootweg]

Pete, was "several years ago" perhaps in the time of HP-UX 9.X, especially on the Series 700? If so, it could be indeed a problem if the root disk was too big, bigger than 2GB and for some versions even bigger than 1GB. IIRC, it had to do with the disk driver 'wrapping around' when it saw a disk that was bigger than it could handle.

[Pete Randall]

Frank,

Forgive my aging memory cells, but I *think* you're probably right that it was a 9.x system, though I am *pretty sure* it was an 800 rather than a workstation. I've probably got notes somewhere - give me a month or so and I'll see if I can remember where I put them.

Pete

[rick jones]

Indeed, using dd is very simple. As pointed-out being simple it will miss some important things like the network settings. I know someone who cloned with dd and then spent the better part of 10 days figuring-out that all his systms were coming-up with the same MAC address.

I think it would be far better to use the Ignite tools.

[harry d brown jr]

Personally, I'd use mirror/ux, then it "just DOESN'T matter".

live free or die
harry

[Rory R Hammond]

Recently I have done lots of cloneing with 11i. And wanted to wade in some thoughts concerning ip address and mac address.

Before cloning,
I manually edited the /etc/rc.conf.d/net.conf
inserting the correct hostname and IP address. I also modified /var/adm/inetd.sec.

My clone did not have the mac address set in /etc/rc.conf.d, So on bootup the network card got the default mac address.

If for some strange reason the new upgraded System needed to have a different MAC address than the Cards default. You could change it by using the ADVANCE setting option in sam and reconfigure network card selection.

I do recall having mac address problems when cloneing hpux 9X and 10X. All of which was resolved by editing a configuration file in /etc/rc.config.d. But not recently on 11X

Good luck