On Sun, Jul 30, 2023 at 6:51 PM Andrew Rowley <and...@blackhillsoftware.com> wrote:
> On 30/07/2023 2:28 am, Jon Perryman wrote: > > ASK YOURSELF: Name the z/OS Unix feature that sort of fixes the > fundamental design flaw with Unix filesystems just described? > > > > I suspect most people won't think about each user having a unique > filesystem using automount to make their filesystem available. Typical Unix > uses one file system with all users having directories in the /user > directory. > > An automounted filesystem per user has always been a terrible idea. I > think it was given as an example of how you could use automount and > somehow morphed into a recommendation. (Other OSes can e.g. use > automount to mount a remote user filesystem via NFS). > > Reasons it's a bad idea: > > 1) Freespace in the filesystem is not shared between users. This means > that you need much more space than if there was one pool of freespace > shared between all. > Whatever. We use automount, and the "space" wasted is way too trivial to worry about. And HSM can magically free up home filesystem zfs files that aren't used any more. > > 2) It makes simple questions like e.g. "Which users have a > .ssh/authorized_keys file?" much harder to answer. > gil answered that one... if you really have a good reason to go poking around in users' business. > > A filesystem per user is basically equivalent to a SMS storage group and > catalog per user. You get isolation between users, but at the expense of > much more difficult management. > Now that you mention it, a catalog per user sounds like a great idea. I suppose it's the nature of our business, but we badly damage catalogs more often than I'd care to admit. We have a few expert Catalog Surgeons*, but the downtime and their time are an expense. The only issue I see is how that might affect CAS. *If my company would license Catalog Recovery+, we would only need to be Catalog Nurse Practitioners. > > -- > Andrew Rowley > Black Hill Software > > sas ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
