What's the difference between dd and cat > ?

kimchee411 · 02-27-2009, 06:20 PM

Hi there,

So I went to VMWare training this week and one of the processes for P2V conversion involves booting to a Linux live CD on the physical server and executing:

cat /dev/[Pdisk1] > //[NFS server]:/[share]/[temp]

and then booting to the Linux CD on the VM and executing:

cat //[NFS server]:/[share]/[temp] > /dev/[Vdisk1]

I never knew you could use cat and redirection to clone a device, so my question is what's the difference between cat > and dd?

Thanks

frieza · 02-27-2009, 06:24 PM

my guess is dd is more precise

r3sistance · 02-27-2009, 06:28 PM

Cat is meant for Catenation, it's meant for merging multiple files together.

Cat file1 file2 > mergedfile

DD is meant for proper low level copying of data as such for turning a CD into an .iso.