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| __TOC__ | | __TOC__ |
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− | Typical external resource when dumping a container (especially LXC/Docker) -- is a mount point whose root sits outside of the container's root. This situation was intended to be resolved using [[plugins]] but turned out to be ''so'' frequent, that we introduced a non-plugin way of handling them.
| + | One of typical external resources when dumping a container (especially LXC/Docker) is a mount point whose root sits outside of the container's root. This situation was intended to be resolved using [[plugins]] but turned out to be common enough to introduce a built-in way of handling it. |
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| == What is external bind mount == | | == What is external bind mount == |
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| == How to teach CRIU to dump them == | | == How to teach CRIU to dump them == |
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− | By default CRIU doesn't dump such mountpoints, because there's no way CRIU will be able to restore it -- the root of these mounts is out of the scope of what CRIU dumped. In the logs you would see the message like | + | By default CRIU doesn't dump such mountpoints, because there's no way CRIU will be able to restore it -- the root of these mounts is out of scope of what CRIU dumped. In the logs you would see a message like |
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| 34:/bar doesn't have a proper root mount | | 34:/bar doesn't have a proper root mount |
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− | which will mean, that the mountpoint /bar has inaccessible root. | + | which means the mountpoint /bar has inaccessible root. |
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| To dump and restore them there's the <code>--external mnt[KEY]:VAL</code> option that sets up external mounts root mapping. | | To dump and restore them there's the <code>--external mnt[KEY]:VAL</code> option that sets up external mounts root mapping. |
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− | On dump, KEY is a mountpoint inside container and correspoding VAL is a string that will be written into the image as mountpoint's root value. | + | On dump, KEY is a mountpoint inside container, and corresponding VAL is a string that will be written into the image as mountpoint's root value. |
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− | On restore KEY is the value from the image (VAL from dump) and the VAL is the path on host that will be bind-mounted into container (to the mountpoint path from image). | + | On restore, KEY is the value from the image (VAL from dump), and the VAL is the path on host that will be bind-mounted into container (to the mountpoint path from image). |
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| For example, if we want to dump the task above we should call | | For example, if we want to dump the task above we should call |