Can the mounted file system be kept on another host if the VM is evacuated?

ph flag

I'd like to know about OpenStack High Availability.
If the node (VM) mounts the file system and the VM is evacuated in case of failure and moved to another host, can the mounted file system be kept on another host?

Thank you!

us flag

It depends on your storage backend.

OpenStack volumes can have a setting multiattach. When set to true the same volume can be made available to two or more compute instances (VM's) concurrently.

It is the responsibility of the compute instance to ensure data integrity for such volumes; a normal file system does not support two or more different nodes writing concurrently to the same block device. You will need a cluster file system or a method to ensure that only one node at the same time will make changes to the block device.


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