Are there any dangers of multiple containers bind mounting the same directory and writing to it? I assume the host handles the actually writing so things stay in sync and there aren't any collisions but I just wanted to check.
A bind mount is a bind mount - all writes are handled by the host kernel. So there is no concurrency control, like with any other linux file system (not sure if I understand your question correctly).
You need a file server aka samba, nfs and so on - can provide a lock system or a concurrent writing from many clients.
yes (if the file system supports that kind of locks).
You need a file server aka samba, nfs and so on - can provide a lock system or a concurrent writing from many clients.
This is not required if all containers are on the same node.
It will be ZFS. To echo what Pablo said, I was wondering if multiple containers could write to a bind mounted directory without issue.
This is not desirable for me as unprivileged containers can't mount samba or NFS shares without compromising security.