On Tue, 2004-02-24 at 20:58, [EMAIL PROTECTED] wrote: > I am looking for some directions or a linux app (preferably something > <snip> On Tue, 2004-02-24 at 23:06, Bopolissimus Platypus wrote: > dd? > <snip>
one thing about dd, when we operate with dump, as well as other read write actions, the write operations are being cached by the kernel, specialy on large copies when there are lots of awaiting write operations that are waiting its turn to be flushed on the disk by the kernel. when dd reads the filesystem through the block device, it will get corrupted versions of some files *if* there are other raw i/o operations unrelating to the dumping procedure. example of this would be, while you are dumping while copying something on the source disk. <im not sure if kernel suppose to have some necessary locking procedures relating to this> we know that when we dump, we dump the entirety of a disk, even its whole metadata(fs structure). so when you encounter the above example and the metadata would be corrupted, then everything you dumped would be entirely useless/unreadable. i have tested this on a floppy and it proved correct :0. the point is, it is safest to dump on an unmounted, on a read-only or on a idle filesystem, syncing it first befored dumping it. make sure you are disk dumping while the source disk is not on its 'inconsistent' state (eg. writing something in it, some other data insertions, etc...) *just a notice*. hth ---------------- - stderr(Cagayan de Oro) -- Philippine Linux Users' Group (PLUG) Mailing List [EMAIL PROTECTED] (#PLUG @ irc.free.net.ph) Official Website: http://plug.linux.org.ph Searchable Archives: http://marc.free.net.ph . To leave, go to http://lists.q-linux.com/mailman/listinfo/plug . Are you a Linux newbie? To join the newbie list, go to http://lists.q-linux.com/mailman/listinfo/ph-linux-newbie
