2016-11-29 03:14:20 +00:00
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# Mounts
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2016-12-16 01:31:19 +00:00
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Mounts are the main interaction mechanism in containerd. Container systems of
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2016-11-29 03:14:20 +00:00
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the past typically end up having several disparate components independently
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perform mounts, resulting in complex lifecycle management and buggy behavior
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when coordinating large mount stacks.
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2016-12-16 01:31:19 +00:00
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In containerd, we intend to keep mount syscalls isolated to the container
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2016-11-29 03:14:20 +00:00
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runtime component, opting to have various components produce a serialized
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representation of the mount. This ensures that the mounts are performed as a
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unit and unmounted as a unit.
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From an architecture perspective, components produce mounts and runtime
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executors consume them.
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2017-02-10 02:52:25 +00:00
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More imaginative use cases include the ability to virtualize a series of mounts
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2016-11-29 03:14:20 +00:00
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from various components without ever having to create a runtime. This will aid
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in testing and implementation of satellite components.
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## Structure
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The `Mount` type follows the structure of the historic mount syscall:
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| Field | Type | Description |
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|-------|----|-------------|
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| Type | `string` | Specific type of the mount, typically operating system specific |
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| Target | `string` | Intended filesystem path for the mount destination. |
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| Source | `string` | The object which originates the mount, typically a device or another filesystem path. |
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| Options | `[]string` | Zero or more options to apply with the mount, possibly `=`-separated key value pairs. |
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We may want to further parameterize this to support mounts with various
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helpers, such as `mount.fuse`, but this is out of scope, for now.
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