On Tue, Jul 7, 2020 at 9:29 AM Per Jessen <per@computer.org> wrote:
Roger Oberholtzer wrote:
Why NFS? Mainly because it is easy to share and unshare directories independently. The server maintains a disk array with 24 removable disks (hot swappable). These disks come and go independently. So they need to be exported and unexported independently. I do not see how to do this with SAMBA. All is in one big file and they are shared and unshared together. We do not want to disrupt some disks while changing others. So NFS seemed a way to go. If I have missed something in SAMBA, I would be ever so happy. That was question two.
You have 24 disks with 24 individual filesystems, and those are exported via NFS. I am sure you can do the same with samba.
A samba share: [photos] comment = Photos directory path = /home/per/photos read only = No inherit acls = Yes
No reason why you shouldn't have 24 of those ? I expect shares can also be added and removed dynamically, I just don't know how :-)
I know that I tried this initially with NFS. We mount everything under /array (not very creative). A udev rule senses when a disk is inserted, and it is then automatically mounted and exported based on the physical slot. We thought we would just mount /array on the clients, and the things under this would just be there or not. This did not work as we expected. I think that we later found that there is an option to NFS (client or server, I don't remember) that causes it to keep what the client sees up-to-date when things in the export are changed (unmounted/mounted things somewhere in the share). But I think we never did get that to work as expected. I should add that on the Linux NFS clients, the remote disks are automounted as they are needed. This has the advantage that if a disk is not inserted on the server (it is not exported), it cannot be mounted on the client, and the mount point remains unavailable. Otherwise one can wind up writing to the directory 'under' the mount point, if you know what I mean. If they only mount /array, I don't know how the clients will see if a disk under /array is really mounted, or if they are just writing to the directory on which the disk should have been mounted. I think we need to explore this option for NFS again. As long as the clients will know when a disk is in fact not available. As to CIFS, I have no idea. I will definitely try simply sharing /array and see what happens. I am just curious what happens when a disk is not in the array. What does the client see? What happens if they try to write to the directory where the disk would have been had it been inserted? It is interesting that on Windows, there is a mount/umount command. It has basically the same syntax as the Unix/Linux command. What is strange is that it is per login. So, if two people have ssh to the Windows computer at the same time, each will need to mount/umount the shares. I cannot decide if that is good or bad. -- Roger Oberholtzer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org