Re: full backup remotely?
2009/12/30 Hetz Ben Hamo het...@gmail.com Hi, Does anyone knows a way (or an app) to backup a full Linux machine remotely to another drive? I'm not talking file based backup, but partition based backup (creating a ghost image). I need to do such a backup without physically travelling to the hosting company. I worked with this kind of problem around two weeks ago, What is the nature of the parrtion ? LVM / truecrypt/ RAW (normal). In some cases you can work with RO based copy (the root parttion is remounted as read only all write go to tmpfs). Please describe the need and the situation. Thanks, Hetz -- my blog (hebrew): http://benhamo.org Skype: heunique MSN: hetz-b...@benhamo.org ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il -- -- -- Boris Shtrasman |Gnu/Linux Software developer | | IM : bori...@jabber.org | | URL : myrtfm.blogspot.com| ___ ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
To avoid changes on the fly its possible to use snapshot. I am wondering, what will happen if ill feed dd through gzip. Will it compress the empty spaces ? -- Michael Ben-Nes - Internet Consultant and Director. http://www.epoch.co.il - weaving the Net. Cellular: 054-4848113 -- On Thu, Dec 31, 2009 at 1:03 AM, Tzafrir Cohen tzaf...@cohens.org.ilwrote: On Thu, Dec 31, 2009 at 12:35:48AM +0200, sammy ominsky wrote: On 31/12/2009, at 00:27, Hetz Ben Hamo wrote: doing the backup. dd is nice, but that will copy also the empty space (although it won't have impact on the size of the backup, it will have an impact on the time it takes). dd has a --sparse flag which makes it not copy empty space. I don't see such a flag in the man page. partimage avoids copying any free block (block marked as free by the file system). If that block also happens to be zeroed out, dd is not aware of such details. And frankly can't safely be aware of them if Hetz want to copy a mounted partition. Also note that if you use dd to copy a mounted partition, you copy different parts of it in different times. This is tricky at best. Unless you e.g. use an LVM with a snapshot. tar (or any other backup of files) is safer. Even there you don't get a complete snapshot of the system. But at least every file is valid. -- Tzafrir Cohen | tzaf...@jabber.org | VIM is http://tzafrir.org.il || a Mutt's tzaf...@cohens.org.il || best ICQ# 16849754 || friend ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
On Dec 31, 2009, at 11:58 AM, Michael Ben-Nes wrote: To avoid changes on the fly its possible to use snapshot. I am wondering, what will happen if ill feed dd through gzip. Will it compress the empty spaces ? At that level there are NO empty spaces. Every block has something in it. What you call empty space is just blocks that have not been allocated to a file. If the disk has never been used since the last full format, the blocks contain zeros, and will compress to almost nothing. As the disk gets used, the blocks continue to contain the same data they did when they contained files, unless you erase files as you delete them. I know MacOS has such an option if you empty the trash, but the base operating system underneath (BSD) does not. I've never heard of there being a Linux option to do so, but there might be. I still don't understand this fascination with DD. It produces an image of the file system, but does anyone really want that? Unless you are going to place it back on the same device, or an exact duplicate, it's not very good. You can easily end up with an unreadable file system, empty space, etc. The only advantage I can see to doing it is that you don't have as much overhead because you are not opening each file. A single read error will crash the backup. Better IMHO to use tar or rsync. Geoff. -- geoffrey mendelson N3OWJ/4X1GM Jerusalem Israel geoffreymendel...@gmail.com New word I coined 12/13/09, Sub-Wikipedia adj, describing knowledge or understanding, as in he has a sub-wikipedia understanding of the situation. i.e possessing less facts or information than can be found in the Wikipedia. ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
2009/12/30 Hetz Ben Hamo het...@gmail.com: Hi, Does anyone knows a way (or an app) to backup a full Linux machine remotely to another drive? I'm not talking file based backup, but partition based backup (creating a ghost image). I need to do such a backup without physically travelling to the hosting company. Sounds like a job for dump+ssh+dd, something like (UNTESTED, UNCHECKED in docs, etc.) dump -0f - /dev/sda1 | bzip2 | ssh y...@remote.machine.com dd of=/path/to/backup.bz2 (definitely check options of dump - I am rusty). -- Oleg Goldshmidt | o...@goldshmidt.org ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
On 30/12/2009, at 17:38, Hetz Ben Hamo wrote: Does anyone knows a way (or an app) to backup a full Linux machine remotely to another drive? I'm not talking file based backup, but partition based backup (creating a ghost image). I need to do such a backup without physically travelling to the hosting company. dd, tar and ssh. --sambo ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
The dd approach is problematic. One problem is, that half full partition might take as many space as a full partition. This is a software written for this specific purpose. There's also a minimal linux system bootable disk with it. http://www.partimage.org/Main_Page On Wed, Dec 30, 2009 at 7:54 PM, sammy ominsky s...@avoidant.org wrote: On 30/12/2009, at 17:38, Hetz Ben Hamo wrote: Does anyone knows a way (or an app) to backup a full Linux machine remotely to another drive? I'm not talking file based backup, but partition based backup (creating a ghost image). I need to do such a backup without physically travelling to the hosting company. dd, tar and ssh. --sambo ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
On 30/12/2009, at 20:34, Elazar Leibovich wrote: http://www.partimage.org/Main_Page Neato. --sambo ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
i prefer clonezilla.org, a similar project, but a bit more well-rounded in my opinion. very easy to use - for windows backups as well as linux. tom. 2009/12/30 sammy ominsky s...@avoidant.org On 30/12/2009, at 20:34, Elazar Leibovich wrote: http://www.partimage.org/Main_Page Neato. --sambo ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
Hi Tom, Sammy Both CloneZilla and Partimage require that I unmount the partition before doing the backup. dd is nice, but that will copy also the empty space (although it won't have impact on the size of the backup, it will have an impact on the time it takes). I need something like Partimage, but without unmounting the partitions. Thanks, Hetz 2009/12/30 Tom Goren motne...@gmail.com i prefer clonezilla.org, a similar project, but a bit more well-rounded in my opinion. very easy to use - for windows backups as well as linux. tom. 2009/12/30 sammy ominsky s...@avoidant.org On 30/12/2009, at 20:34, Elazar Leibovich wrote: http://www.partimage.org/Main_Page Neato. --sambo ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il -- my blog (hebrew): http://benhamo.org Skype: heunique MSN: hetz-b...@benhamo.org ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
On 31/12/2009, at 00:27, Hetz Ben Hamo wrote: doing the backup. dd is nice, but that will copy also the empty space (although it won't have impact on the size of the backup, it will have an impact on the time it takes). dd has a --sparse flag which makes it not copy empty space. --sambo ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
On Thursday 31 December 2009, Hetz Ben Hamo wrote: Hi Tom, Sammy Both CloneZilla and Partimage require that I unmount the partition before doing the backup. dd is nice, but that will copy also the empty space (although it won't have impact on the size of the backup, it will have an impact on the time it takes). I need something like Partimage, but without unmounting the partitions. IIRC you have to choose - unmount and partition backup or keep mounted and backup the files. You can't keep the mount and use dd or similar. --y signature.asc Description: This is a digitally signed message part. ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
On Thu, Dec 31, 2009 at 12:35:48AM +0200, sammy ominsky wrote: On 31/12/2009, at 00:27, Hetz Ben Hamo wrote: doing the backup. dd is nice, but that will copy also the empty space (although it won't have impact on the size of the backup, it will have an impact on the time it takes). dd has a --sparse flag which makes it not copy empty space. I don't see such a flag in the man page. partimage avoids copying any free block (block marked as free by the file system). If that block also happens to be zeroed out, dd is not aware of such details. And frankly can't safely be aware of them if Hetz want to copy a mounted partition. Also note that if you use dd to copy a mounted partition, you copy different parts of it in different times. This is tricky at best. Unless you e.g. use an LVM with a snapshot. tar (or any other backup of files) is safer. Even there you don't get a complete snapshot of the system. But at least every file is valid. -- Tzafrir Cohen | tzaf...@jabber.org | VIM is http://tzafrir.org.il || a Mutt's tzaf...@cohens.org.il || best ICQ# 16849754 || friend ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
Re: full backup remotely?
fools - listen to oleg - use 'dump' and 'restore'. --guy Tzafrir Cohen wrote: On Thu, Dec 31, 2009 at 12:35:48AM +0200, sammy ominsky wrote: On 31/12/2009, at 00:27, Hetz Ben Hamo wrote: doing the backup. dd is nice, but that will copy also the empty space (although it won't have impact on the size of the backup, it will have an impact on the time it takes). dd has a --sparse flag which makes it not copy empty space. I don't see such a flag in the man page. partimage avoids copying any free block (block marked as free by the file system). If that block also happens to be zeroed out, dd is not aware of such details. And frankly can't safely be aware of them if Hetz want to copy a mounted partition. Also note that if you use dd to copy a mounted partition, you copy different parts of it in different times. This is tricky at best. Unless you e.g. use an LVM with a snapshot. tar (or any other backup of files) is safer. Even there you don't get a complete snapshot of the system. But at least every file is valid. ___ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
