Drive to Drive Copy

lunarcloud_88 · 07-27-2005, 06:59 PM

Is there a program to assist in complete drive-to-drive copying?
I use slackware linux, btw.

macemoneta · 07-27-2005, 08:35 PM

The command you want is 'dd'. Assuming the drives are the same size (or the destination is larger):

dd if=/dev/hde of=/dev/hdf

The above will copy every block from the source (/dev/hde in this example) to the destination (/dev/hdf in the example). You can increase the buffering which may speed the copy if you have the memory, by specifying the 'bs' option:

dd if=/dev/hde of=/dev/hdf bs=4M

The above will set the block size to 4MB.

lunarcloud_88 · 07-29-2005, 09:24 AM

does the second drive have to be formatted first? if so... how do i do that. cfdisk let's me tell it to be "linux" format, but i had to go through the slack installer to actually make it ext3. how do i format it in ext3 then?

macemoneta · 07-29-2005, 09:38 AM

You don't need to format it before the copy - any existing format will be overwritten. All blocks, including the filesystem overhead, partition tables, master boot record, etc. are being copied.

To format a partition as ext3, the command is (where /dev/hdx1 is the partion you want to format):

mke2fs -j /dev/hdx1

An ext3 partition is an ext2 partition with a journal (the -j option).

lunarcloud_88 · 07-29-2005, 09:48 AM

Will that also work for partitions?
If i just say dd if=/dev/hda1 of=/dev/hdb2
... will it just copy those partitions or will it try to copy the entire hard drives (therefore wiping files i need.)?

macemoneta · 07-29-2005, 09:54 AM

It will just copy those partitions.

phil.d.g · 07-29-2005, 09:55 AM

that will just copy hda1 to hdb2, hdb2 must be the same size or bigger

lunarcloud_88 · 07-29-2005, 09:59 AM

i plan on having it much bigger. Thanks guys!

macemoneta · 07-29-2005, 10:04 AM

Having it much bigger? If you are planning to expand the partition by moving to a larger partition, you will need the resize2fs command.

lunarcloud_88 · 07-30-2005, 09:48 AM

ok... now that i've moved it and realized it thinks its the same sized partition... how to i do that?
Can I be using the partition to be enlarged while running resize2fs?
Do I have to specify -j for ext3?

macemoneta · 07-30-2005, 10:11 AM

No, you don't want to use it while it's being resized. It should not be a mounted partition. To resize it (assuming it's called /dev/hdb2) to fill the new partition:

resize2fs -p /dev/hdb2

Check the man page for details.

lunarcloud_88 · 07-30-2005, 05:37 PM

i've done it and made the necessary changes to /etc/fstab thanks guys!

NuWeb · 11-14-2006, 05:59 AM

I'm a bit new to linux.

I have a 80Gig WD drive that's about to die. I purchased another 80Gig WD drive and partitioned the drive the same as the first drive. I did "dd if=/dev/hda of=/dev/hdb" and the hard drive light started flickering. This has been going on for about 6 hours.

How long should it take to completely copy an 80 Gig drive.?

Thanks...

pixellany · 11-14-2006, 07:52 AM

Quote:

Originally Posted by NuWeb

I'm a bit new to linux.

I have a 80Gig WD drive that's about to die. I purchased another 80Gig WD drive and partitioned the drive the same as the first drive. I did "dd if=/dev/hda of=/dev/hdb" and the hard drive light started flickering. This has been going on for about 6 hours.

How long should it take to completely copy an 80 Gig drive.?

Thanks...

Normally better to start a new thread--but you question is pretty close to the original....

To use dd, there is no need to partition anything--it is doing low-level copy---bit by bit.

An easy way to answer your question **for your machine**:
dd if=/dev/hda of=/dev/hdb bs=1M count=10
See how long that takes...the same command without "count=10" will take 8,000 times longer (80GB/10MB)'

Also, I think dd goes faster when you specify a larger block size--I've never played with it though

NuWeb · 11-14-2006, 08:01 AM

Quote:

Originally Posted by pixellany

Normally better to start a new thread--but you question is pretty close to the original....

To use dd, there is no need to partition anything--it is doing low-level copy---bit by bit.

An easy way to answer your question **for your machine**:
dd if=/dev/hda of=/dev/hdb bs=1M count=10
See how long that takes...the same command without "count=10" will take 8,000 times longer (80GB/10MB)'

Also, I think dd goes faster when you specify a larger block size--I've never played with it though

Like I said, I'm new to this.

It's been going for 8 hours, should I stop it and start again.?

What should I use for the best results (the "EXACT" command line) and how long should it take to copy the drive.?

Since I partitioned the drive is there anything I need to do or does it just rewrite over everything.?

Thanks again...