[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: Is there a Linux ghost?



Hi
Well, about the slowness,
If I recall correctly, I managed to duplicate a scsi 10GB disk in between
5-10  minutes this way, but I don't remember the speed of the disk.
playing with the block size should vary the performance.

About the disk sizes, I never tested it, but i think that if u duplicate a
smaller disk to a bigger disk it should work. (but i'm really not sure about
this one :( )
But even if the disk size are not identical, u can still make even sized
partitions on separate disks, and dd the partitions.



-----Original Message-----
From: linux-il-bounce@cs.huji.ac.il [mailto:linux-il-bounce@cs.huji.ac.il]On
Behalf Of Nadav Har'El
Sent: Wednesday, September 05, 2001 11:17 AM
To: Ori Hanegby
Cc: 'Daniel Feiglin'; linux-il@linux.org.il
Subject: Re: Is there a Linux ghost?



But watch out - this can be S-L-O-W for the huge disks (20GB) of today...
Just think about it - if it can copy (read and then write) 5MB a second (I'm
just making up a number) it will take over an hour to copy 20GB...

Usually, much of the disk doesn't need to be copied: only about 2GB will
contain prebundled software (hopefully a Linux system!!), and the rest
can be generated again and again by "mkfs"ing empty file systems,
"mkswap"ing
swap partitions, and so on. It's easy to copy only one partition, by copying
/dev/hda1 (for example), not the whole /dev/hda. Of course, you'll need to
copy the partition table first - I recommend sfdisk(8).

Whether such an optimization is worthwhile to you depends on what kind of
installation you're trying to do, and how many times you're going to repeat
the same installation.

Of course, all the replies you got (including this one) assume that both
disks are identical (same capcity, layout, etc.). If they're not, this whole
dd approach probably wouldn't work.

--
Nadav Har'El                        |     Wednesday, Sep  5 2001, 17 Elul
5761
nyh@math.technion.ac.il
|-----------------------------------------
Phone: +972-53-245868, ICQ 13349191 |May you live as long as you want - and
http://nadav.harel.org.il           |never want as long as you live.

=================================================================
To unsubscribe, send mail to linux-il-request@linux.org.il with
the word "unsubscribe" in the message body, e.g., run the command
echo unsubscribe | mail linux-il-request@linux.org.il


=================================================================
To unsubscribe, send mail to linux-il-request@linux.org.il with
the word "unsubscribe" in the message body, e.g., run the command
echo unsubscribe | mail linux-il-request@linux.org.il