Assuming those instances all need shared access to that storage, you would have to build some sort of shared storage on top of the ZFS solution. This might mea

Assuming those instances all need shared access to that storage, you would have to build some sort of shared storage on top of the ZFS solution. This might mean NFS shares, or a relational database, etc, depending on the nature of the shared data. You still end up with a single point of failure at the storage layer, and a potential performance bottleneck. If the data they need shared access to is immutable (for example, the static files served by a webserver) I would much sooner bake them into a versioned container image and share that. It'll perform better by virtue of being on unshared local storage and eliminate the single point of failure/bottleneck. Another option for eliminating the single point of failure and performance bottleneck is a distributed filesystem like cephfs or glusterfs.