On 7 Oct 2010 at 17:36, Bill Davidsen wrote: To: users@xxxxxxxxxxxxxxxxxxxxxxx From: Bill Davidsen <davidsen@xxxxxxx> Subject: Re: rsync or dd to clone a hard drive? Date sent: Thu, 07 Oct 2010 17:36:08 -0400 Send reply to: Community support for Fedora users <users@xxxxxxxxxxxxxxxxxxxxxxx> <mailto:users- request@xxxxxxxxxxxxxxxxxxxxxxx?subject=unsubscribe> <mailto:users- request@xxxxxxxxxxxxxxxxxxxxxxx?subject=subscribe> > Kwan Lowe wrote: > > On Wed, Oct 6, 2010 at 12:23 PM, Patrick Bartek<bartek047@xxxxxxxxx> wrote: > >> I would use dd to clone (or back up) an entire hard drive. Easier. You can even pipe it through gzip to get a compressed image file. > > > > I do exactly that... dd piped through gzip then push through an SSH > > session to a remote where it's extracted and written on the fly to > > another LV. I use it to move kvm LVs from machine to machine. Works > > great, but there's not much error checking. If it's critical I do an > > md5sum on the LVs at the end then compare. > Cut part. Some comments on Compression. With my G4L project that backs up and restores disk and partitions using dd and compression. I've also seem difference in the speed and load on cpu. I've used lzop compression as the default option do to this. In a small partition test these were the time results. 10 seconds with no compression 3 seconds with lzop compression 6 seconds with gzip compression 18 seconds with bzip compression With full disk images the same machines take the following. 50 minutes with lzop 100 minutes with gzip Intestingly, restoring both the lzop and gzip images only takes about 40 minutes, so compression process takes more load compared to uncompressing. The general difference between the compression is about 10%. Also, lzop only seems to load the CPU at about 30% rather than the 80 - 90% of gzip. There are lots of things that effect the speed, so this might vary based on the overall system and network. Good Luck. > Bill Davidsen <davidsen@xxxxxxx> > "We have more to fear from the bungling of the incompetent than from > the machinations of the wicked." - from Slashdot > > -- > users mailing list > users@xxxxxxxxxxxxxxxxxxxxxxx > To unsubscribe or change subscription options: > https://admin.fedoraproject.org/mailman/listinfo/users > Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines +----------------------------------------------------------+ Michael D. Setzer II - Computer Science Instructor Guam Community College Computer Center mailto:mikes@xxxxxxxxxxxxxxxx mailto:msetzerii@xxxxxxxxx http://www.guam.net/home/mikes Guam - Where America's Day Begins G4L Disk Imaging Project maintainer http://sourceforge.net/projects/g4l/ +----------------------------------------------------------+ http://setiathome.berkeley.edu (Original) Number of Seti Units Returned: 19,471 Processing time: 32 years, 290 days, 12 hours, 58 minutes (Total Hours: 287,489) BOINC@HOME CREDITS SETI 10009860.871197 | EINSTEIN 4666047.880851 ROSETTA 2301696.375998 | ABC 2782904.713840 -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
