On Fri, 12 Sep 2003, Jim Norton wrote:
Perhaps a stupid question or two.
(No, not stupid at all IMO.)
#1 - How does backup an entire installation using dd?
I use, e.g.: # cd /huge-filesystem/lots-of-space # dd if=/dev/hda0 of=hda0.ext3.img bs=1024k You can tune the "bs=" parameter for best performance if you desire. I name the backup file with the filesystem type and something to indicate that it is a filesystem image. I tend to do some of my backups nowadays as filesystem image files since it allows me to easily loopback mount them to retrieve a file, etc. BTW, I do my regular backups (ext3, xfs) using the appropriate "dump" program (e.g., the ext[23] /sbin/dump program). The disadvantage of using "dd" for backups is that it backs up the -entire- filesystem, including unallocated space and so will always take up as much space on the backup media as the entire filesystem. Other backup progs, such as "dump", "tar", "cpio", etc., only back up existing files and ignore empty space in the filesystem.
#2 - And is it possible to pipe the dd output to an ethernet connection to another Linux box so that 'backup' can be on a drive on another machine? Would NFS work with dd?
I would use something like: # dd if=/dev/hda0 | ssh user@otherhost 'cd /huge-filesystem/lots-of-space && dd of=hda0.ext3.img' Yes, NFS also works with "dd", i.e., the target filesystem may be NFS mounted from another system. Hope this helps! Phil -- Philip Amadeo Saeli SuSE Linux 8.2 psaeli@zorodyne.com