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On 2019-12-10 13:44, Rich Freeman wrote: |
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> I'm not talking about container-host mapping. I'm talking about |
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> building the same container 100 times and having the container end up |
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> with the same UIDs inside each time. |
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> |
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> Build order in portage isn't really deterministic, especially over |
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> long periods of time, so you can't rely on stuff getting installed in |
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> the same order. |
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|
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While I agree that portage doesn't guarantee you |
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deterministic/reproducible builds, in practice this isn't a problem: |
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|
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Assume you are building a container for dev-db/mysql. I can only think |
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of one scenario where you would end up with different UIDs: That's when |
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dev-db/mysql (or a dependency) would suddenly create an own user and |
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will be merged before mysql's user was created. |
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|
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But this is very theoretically. Especially in a container world, you |
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will create one container per services so it's *very* unlikely that |
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something like that will ever happen. Not? |
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|
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Aside benefits from reproducible builds in general (which Gentoo doesn't |
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provide), please share reasons why one would care about used UIDs/GIDs |
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in containers... |
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|
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|
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> Uh, the container processes shouldn't even see the host |
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> processes/files whether they have the same UIDs or not... |
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Especially when you put mysql or any other service using data into a |
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container, service running in that container must be able to access this |
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data. And one common way to do that is allowing container to access data |
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stored on host, i.e. |
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|
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> $ docker run \ |
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> --name some-mysql \ |
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> -v /my/own/datadir:/var/lib/mysql \ |
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> -e MYSQL_ROOT_PASSWORD=my-secret-pw \ |
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> -d mysql:tag |
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|
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which will make /my/own/datadir from host available in container as |
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/var/lib/mysql. |
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|
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|
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-- |
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Regards, |
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Thomas Deutschmann / Gentoo Linux Developer |
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