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Linux - Hard Drive DD Question - restoring a backup to a larger drive?
Let's say that I backup a hard drive like so:
This sends a backup of a 75GB hdd to a receiving computer
dd if=/dev/sda | nc IP PORT
Now let's say I buy a 150 GB hdd when the 75GB hdd fails
Time to restore the backup (computer receiving data onto the new hdd)
nc -l -p 1234 | dd of=/dev/sda
1. Can I write directly to a drive like this? (I know the first command works, but what about the second? I'm concerned about writing to an unmounted drive, even though I can read from it)
2. What happens to the other 75 GB of the new hard drive that don't get filled up with data? Will this drive even be usable?
Thanks
This sends a backup of a 75GB hdd to a receiving computer
dd if=/dev/sda | nc IP PORT
Now let's say I buy a 150 GB hdd when the 75GB hdd fails
Time to restore the backup (computer receiving data onto the new hdd)
nc -l -p 1234 | dd of=/dev/sda
1. Can I write directly to a drive like this? (I know the first command works, but what about the second? I'm concerned about writing to an unmounted drive, even though I can read from it)
2. What happens to the other 75 GB of the new hard drive that don't get filled up with data? Will this drive even be usable?
Thanks
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ASKER
ktd85, I have great news to round out this question. I'm going to provide some info to anybody else who stumbles across this question that was in a similar situation.
I hooked up an old 250gig hard drive in place of the suspected-broken 75gig HDD.
I issued this command on the backup-pc: dd if=backup.img | nc IP Port
I issued this command on the receiving-pc: nc -l -p 1234 | dd of=/dev/hda
It's working.
Furthermore, I moved over to use dd_rescue which provides some great run-time output:
backup-pc: dd_rescue -b 65535 -v backup.img.gzip | nc IP Port
Receiving PC: nc -l -p 1234 | gzip -cdf | dd_rescue -v - /dev/hda
This takes the gzip'd 75gig-HDD backup and sends it across the network to the receiving PC (The PC that is receiving the back). When the receiver receives data, the data is decompressed and fed through dd_rescue to the new hard drive.
backup-pc is running ubuntu server 6 with dd_rescue apt-get installed with a 1 terabyte usb hard drive mounted
receiving-pc is running trinity rescue live cd, booted in default mode.
If there are any questions on how to do this, post to this question and i'll try to help out
Thanks again for the help ktd85
I hooked up an old 250gig hard drive in place of the suspected-broken 75gig HDD.
I issued this command on the backup-pc: dd if=backup.img | nc IP Port
I issued this command on the receiving-pc: nc -l -p 1234 | dd of=/dev/hda
It's working.
Furthermore, I moved over to use dd_rescue which provides some great run-time output:
backup-pc: dd_rescue -b 65535 -v backup.img.gzip | nc IP Port
Receiving PC: nc -l -p 1234 | gzip -cdf | dd_rescue -v - /dev/hda
This takes the gzip'd 75gig-HDD backup and sends it across the network to the receiving PC (The PC that is receiving the back). When the receiver receives data, the data is decompressed and fed through dd_rescue to the new hard drive.
backup-pc is running ubuntu server 6 with dd_rescue apt-get installed with a 1 terabyte usb hard drive mounted
receiving-pc is running trinity rescue live cd, booted in default mode.
If there are any questions on how to do this, post to this question and i'll try to help out
Thanks again for the help ktd85
ASKER
Thanks for your time,