What's the point of using tar *for backup* today?
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From: Mark Hobley on 2 Jan 2010 03:08 Karsten Kruse <tecneeq(a)tecneeq.de> wrote: > Eze schrieb: > You could name your tar archives like that: > > full_backup_friday.tar > incremental_backup_monday.tar > incremental_backup_tuesday.tar > incremental_backup_wednesday.tar > incremental_backup_thursday.tar > > That's kind of hard to do with cp. So it's about organisation of your > backups. You could still have untarred backup disks and label the disks as: full_backup_friday incremental_backup_monday incremental_backup_tuesday incremental_backup_wednesday incremental_backup_thursday > > Tar also has many options to choose, it can verify the archive with the > disk content, cp can't do that. It can save space with sparse files, it > works remote via rsh. It can also compress while archiving, unlike cp. You could also do all of the above with a copy utility (albeit you may have to write one). In fact, when I backup to CDR media, I tend not to create a tarball, but write the untarred content straight to the .iso image. I wonder how many other people do this. Mark. -- Mark Hobley Linux User: #370818 http://markhobley.yi.org/
From: Younes Zouhair on 2 Jan 2010 04:06 On 01/02/2010 02:40 AM, Seebs wrote: > On 2010-01-02, Younes Zouhair<poboxy(a)gmail.com> wrote: >> You shouldn't care about what Sidney Lambe, he's just an ignorant troll. >> Most of the time he doesn't know what he's talking about. > > I object strongly to this characterization, on two grounds. > > The first is that to be that consistently wrong, I think he'd actually > have to know a fair amount. > > The second is that I think that the more conventional sorts of trolls are > going to view this as defamatory. > > -s Duly noted!
From: Eze on 2 Jan 2010 04:12 Thanks to all for the answers and the practical advice regarding Usenet. (I promise I'll follow it!)
From: jellybean stonerfish on 2 Jan 2010 05:06 On Fri, 01 Jan 2010 18:20:46 -0800, Eze wrote: >> If you'd just _try_ both methods, you'd soon learn the answer to your >> question. > > I did try, successfully. In fact, lumping many files into one can easily > take you to >4GB, which makes it hard to use the rather common FAT32 > filesystem for external drives, while this is not an issue as long as > your individual files don't go over that limit. I know unix experts > would not use FAT32 at all, but so far I can only see disadvantages. > However, the popularity of tar tells me I'm missing something. For added confusion, you could pipe the output of "tar" through "spit" to break up a huge archive into SIZE sized pieces. tar -cz DIR/TO/SAVE | split -b $SIZE - dir.tar
From: John Koy on 2 Jan 2010 08:08
Don't mind the term "tape", it is about archiving. http://en.wikipedia.org/wiki/Archive_file But for small backup tasks, you're right. Now (Gnu) cp command has several backup related options, I use cp with them for personal backups. The forum post you cite is almost 5 years old, not a current reference. Eze wrote: > I see the point of using tar in order to, say, send a whole directory > as a single attachment file. I realize historically this "tape > archive" utility may have been needed for some technical reasons. But > I don't see the advantages of using tar to back up some files and copy > them to some external storage device. Couldn't you just cp? The files > would already been untarred... > > I bring this up because it has been winner or runner-up of the Linux > Journal Readers' Choice Awards as Favorite Backup Utility for several > years. It is also recommended as a "quick and dirty" backup tool at > http://www.linuxquestions.org/linux/articles/Jeremys_Magazine_Articles/Quick_and_Dirty_Backups. > > Would someone care to shed some light? > > Thanks, > > Eze |