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On 3/8/21 5:52 am, Frank Steinmetzger wrote: |
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> Am Mon, Aug 02, 2021 at 01:38:31PM +0800 schrieb William Kenworthy: |
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> |
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>>> Yup. Today I did my (not so) weekly backup and rsynced the repo to the new |
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>>> drive. After that I wanted to compare performance of my old 3 TB drive and |
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>>> the new SMR one by deleting a snapshot from the repo on each drive. But Borg |
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>>> objected on the second deletion, because “the cache was newer”. But that’s |
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>>> okay. I actually like this, as this will prevent me from chaning two repos |
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>>> in parallel which would make them incompatible. |
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>>> |
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>> Keep in mind that both repos have the same ID - you should also rsync |
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>> the cache and security directories as well as they are now out of sync |
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>> (hence the warning). |
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> That thought crossed my mind recently but I was unsure how to store the |
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> cache. But since the repo is a monolith, it should suffice to rsync |
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> the whole cache directory to the backup drive (or do it as a tar). |
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> |
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> The only problem is the temporal sequence: |
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> 1. Host A runs borg and gets a current cache. |
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> 2. Host B runs borg on the same repo and gets a current cache. |
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> 2a. Host A now has an outdated cache. |
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> |
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> Usually, Host B uses Host A via ssh as remote location of the repository. |
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> So I could simply run a borg command on Host A to update the cache somehow. |
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> |
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>> Be very careful on how you do this - you are one step away from losing the |
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>> while repo if the cache gets out of sync. The docs warn against rsyncing |
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>> two repos and then using them at the same time for a good reason. |
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> I won’t use them at the same time. It will always be one direction: |
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> Hosts --[borg]--> Main backup drive --[rsync]--> secondary backup drive |
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> |
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You could delete and rebuild the cache each time (or I think there is a |
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way to do without it). There are quite a few threads on the borg lists |
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about this in the past (usually people trying to recover trashed repos) |
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- you might ask there if there is a way to deal with changing the ID now? |
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In any case, I think doing it the way you are has a fairly high chance |
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you will irretrievably trash both repos. |
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BillK |
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