Mounting from multiple devices

Hi all,

First off, thank you for developing NBD. I've really been enjoying using it recently - accessing raw block devices over a network fits very well into my various use cases.

However, I've found some conflicting documentation about the _safety_ of accessing an exported block device from multiple clients. Notably, the sourceforge page (https://nbd.sourceforge.io/) states that "if someone has mounted NBD read/write, you must assure that no one else will have it mounted". In contrast, the documentation in the current Linux tree (https://github.com/torvalds/linux/blob/master/Documentation/admin-guide/blockdev/nbd.rst) does omits this sentence, implying that it is okay for multiple clients to mount NBD read/write.

Let's say I have an ext4 filesystem on an NBD. Is it safe for me to mount this filesystem on multiple clients?

Thank you,

Gregor Haas