mount --move and shared namespaces
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It seems that mount --move does not work on a shared namespace ( now the default under systemd ), yet you can mount --bind and then umount the original, which seems to amount to exactly the same thing. Why is the direct move not allowed?
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Quoted 7 lines · Phillip Susi
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Hash: SHA512It seems that mount --move does not work on a shared namespace ( now the default under systemd ), yet you can mount --bind and then umount the original, which seems to amount to exactly the same thing. Why is the direct move not allowed?
You have something mounted on /foo and events from /foo propagated to /bar. You move the instance on /foo to /baz; what to do with one on /bar? Propagation from /baz might have nothing whatsoever in common with that on /foo, so "move to the corresponding recepients of events for /baz" is not an answer...
Move *into* shared is allowed - the one you move ends up relocated and cloned, with clones attached to the places where events propagate to. Move *from* shared... No sane semantics.
And no, mount --move is *not* mount --bind + umount - it really moves the vfsmount, so anything sitting in that subtree will find itself at the new location.