[CentOS] transfer data from one hard drive to another

[chrism at imntv.com]

Lamar Owen wrote:
> On Friday 06 October 2006 22:42, Joseph Cheng wrote:
>   
>> Thx for all the suggestions ppl. I think for simplicity I will either
>> go with the knoppix & dd solution or I also found ghost 4 unix
>> http://www.feyrer.de/g4u/
>>     
>
> I have used the dd solution a number of times, and it works quite well. 
>
> There are, however, a couple of suggestions I would make:
> 1.) Use the CentOS rescue mode (boot CD number 1, type 'linux rescue' at the 
> boot prompt) and tell it not to mount your drives.  No need to download Yet 
> Another Linux Distribution to do the work.  Or use the CentOS LiveCD.
> 2.) While the dd is running, you can check on its progress.  Switch to another 
> virtual console (you are by default on VC 1; hit ALT-F2 to go to VC 2) and 
> send the dd process a SIGUSR1 (run a ps ax and make a note of the dd 
> process's PID; then kill -USR1 $PID); then switch back to VC 1 and you'll see 
> where dd is in your copy.
>
> You can then run fdisk or parted and grow the partition; then you can resize 
> the filesystem (I'm fairly certain the rescue mode includes the resizing 
> program; not sure about the LiveCD, but I would think it does).  The native 
> CentOS tools to do this are, in my experience, far superior in quality to the 
> various third party solutions (including Symantec Ghost) availabe to do this 
> sort of thing.  They are a little harder to use, though they seem to work 
> better.
>   

Interesting.  I wonder if you used this method to copy the image from 
one disk to an identical disk hda-->hdb if you could then unplug hda and 
have the system boot from the "copy" without any other intervention.  
Kind of like a poor man's RAID1 except you only get back to where you 
were at the instant the snapshot was taken.  I've never tried this since 
RAID cards are so cheap, but I guess I'm wondering out loud if that 
would work.  Anyone tried it?

Cheers,