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On Thursday, 9 August 2018 09:18:43 BST Bill Kenworthy wrote: |
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> On 08/08/18 11:43, Dale wrote: |
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> > Howdy, |
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> > |
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> > Long story short that leads up to my questions, I paid off some debt. |
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> |
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> Hi Dale, |
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> |
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> what you are talking about is not a real backup but a single copy of |
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> your data that may or may not be complete (the delete option you |
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> mention) at a single point in time - not quite as useful as a proper |
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> versioned backup. Whatever your choice, also look at the restore |
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> procedure - very important. |
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|
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Well, a static mirror is a full backup at that point in time. If the backed |
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up data changes little over time, it is a valid backup, which can prove its |
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worth if/when the original drive dies, or files are deleted accidentally on |
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the original. |
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|
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On the points Dale raised: |
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|
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The --delete option will remove from the destination any files which no longer |
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exist on the source. So if you delete photo-1 on the source and then run |
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rsync, photo-1 *will* be deleted from the full back up, to mirror what is |
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currently available on the source directory. |
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|
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Here is where incremental/differential backup strategies can be of use, in |
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case some time in the relatively near future you change your mind and wish you |
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never had deleted that old photo-1. The same may apply to user config files, |
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if you stop using an application, manually clean/delete its config files from |
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your home and rsync --delete thereafter. If in the near future you review |
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your position and decide you wanted that application after all and the 2 weeks |
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you had spent configuring it would be of use again, with the --delete option |
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your config files will be gone from the backup. So, use --delete judiciously. |
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|
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rsync can on its own provide you with incremental and differential backups, |
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using hard links to the full backup directory, so as to avoid duplication and |
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minimise storage space usage. This means that incremental backups take only a |
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fraction of the space and additional disks or enclosures may be redundant. |
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Take a look at the --backup, --backup-dir, and --link-dest, options. |
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|
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As others have posted there are a number of applications which use rsync as a |
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back end and have scripted with config files its options. There's also quite |
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a number of bash scripts on the interwebs offering a starting point if you |
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prefer to hack your own. |
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|
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With regards to heat and humidity I suggest you take a look at the |
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manufacturer's specifications, both for the enclosure and for the drives. |
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Invariably environmental thresholds are printed on labels on the devices |
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themselves, or you could google using the part numbers off them. |
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|
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HTH. |
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-- |
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Regards, |
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Mick |