Re: [DNG] Backup revisited - the rsync time machine
On Mon, Feb 05, 2018 at 09:08:59AM -1000, Joel Roth wrote: > On Mon, Feb 05, 2018 at 09:15:33AM -0500, Hendrik Boom wrote: > > On Fri, Feb 02, 2018 at 05:32:36PM -1000, Joel Roth wrote: > > > Dear list, > > > > > > For years I'd used a couple of rsync scripts for backup, > > > usually just full snapshots. > > > > > > I knew there is an option using hardlinks that behaves like > > > the Mac Time Machine app, giving cheap incremental backups. > > > > > > https://blog.interlinked.org/tutorials/rsync_time_machine.html > > > > () > > > probably someone has done it better... > > > > > > > There's rdiff-backup, which uses an efficient algorithm to identify what > > has changed and transmit the diffs over the network. It also keeps a > > history of old backups on the backup drive, so you can restore as of a > > previous date. > > I used rdiff-backup years ago. ISTR it litters the directory tree > with index files. It has index files on the backup, right? They are for storing things like reverse diffs so it can reconstruct old backups. I've never noticed it litterring the actual working file system -- just the backups. -- hendrik ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Backup revisited - the rsync time machine
On Mon, Feb 05, 2018 at 09:15:33AM -0500, Hendrik Boom wrote: > On Fri, Feb 02, 2018 at 05:32:36PM -1000, Joel Roth wrote: > > Dear list, > > > > For years I'd used a couple of rsync scripts for backup, > > usually just full snapshots. > > > > I knew there is an option using hardlinks that behaves like > > the Mac Time Machine app, giving cheap incremental backups. > > > > https://blog.interlinked.org/tutorials/rsync_time_machine.html > > () > > probably someone has done it better... > > > > There's rdiff-backup, which uses an efficient algorithm to identify what > has changed and transmit the diffs over the network. It also keeps a > history of old backups on the backup drive, so you can restore as of a > previous date. I used rdiff-backup years ago. ISTR it litters the directory tree with index files. cheers, > And the files themselves are readable on the backup drive, as ng as you > don't have them compressed or encrypted. > > -- hendrik > ___ > Dng mailing list > Dng@lists.dyne.org > https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng -- Joel Roth ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Backup revisited - the rsync time machine
On Fri, Feb 02, 2018 at 05:32:36PM -1000, Joel Roth wrote: > Dear list, > > For years I'd used a couple of rsync scripts for backup, > usually just full snapshots. > > I knew there is an option using hardlinks that behaves like > the Mac Time Machine app, giving cheap incremental backups. > > https://blog.interlinked.org/tutorials/rsync_time_machine.html > > And now I fool around with it myself. > > Since I have map UUIDs to mount points in /etc/fstab, > I can put the full paths in the backup script > and simply run it without parameters to get a > date-and-time-stamped directory containing a full backup. > > Probably you all have something much better, but for the > sake of discussion, and will post my humble offering. > > The clever part of the code is using a symlink > .../backups/current/ to provide rsync with the --link-dest > argument, the tree of files available for hardlinking during > next backup pass. > > Also, the one-file-system argument to rsync lets me backup > the root directory without pulling in other mounts. > > The current script doesn't support copying over a network, > but can be easily achieved by consulting online resources > (left as an exercise to the reader.) > > Obviously, you will need to configure it. Note that the directories > excluded from backup are created in the last step. > > probably someone has done it better... > There's rdiff-backup, which uses an efficient algorithm to identify what has changed and transmit the diffs over the network. It also keeps a history of old backups on the backup drive, so you can restore as of a previous date. And the files themselves are readable on the backup drive, as ng as you don't have them compressed or encrypted. -- hendrik ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Backup revisited - the rsync time machine
il devuanizzato Joel Roth il 03-02-18 04:32:36 ha scritto: > Dear list, > > For years I'd used a couple of rsync scripts for backup, > usually just full snapshots. > > I knew there is an option using hardlinks that behaves like > the Mac Time Machine app, giving cheap incremental backups. You may try rsnapshot. It is based on rsync and use hard links whenever possible. -- viverna ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
Re: [DNG] Backup revisited - the rsync time machine
On 02.02.18 17:32, Joel Roth wrote: > Probably you all have something much better, but for the > sake of discussion, and will post my humble offering. Not better, but a data point for anyone else backing up to a flash drive, which is convenient for the off-site backup. Rsync compares checksums between source and destination, reprocessing a single write fail, and erroring on a second. BUT, if the flash drive has bit drop-outs after time, then that isn't detectable by rsync. Files not updated in a subsequent backup remain corrupted, and any updated are simply overwritten, and liable to repeated bit loss. OK, I've only ever had one flash drive which started to lose bits (in 6% of files before I detected it), but my backup script now does a diff -qr on the backup after the rsync. It's a bit time consuming, but you don't have to watch it. Erik ___ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
