[HECnet] OpenVMS Backup

[Brian Schenkenberger, VAXman-]

G. <gerry77 at mail.com> writes:

On Wed, 22 May 2013 14:00:08, h vlems wrote:

Move all data directories on an LD to an aptly named top directory and=20
mount/bind all the ld disks?=20

If I'm not wrong, MOUNT/BIND does not work if more than one disk contains
files. In other words, when you bind a number of disks, you'll see only =
files
located in the first one. Bind was conceived when physical disks were so =
small
that some applications space needs exceeded single-disk capacities =
available.

HELP MOUNT /BIND says:

|           Note that if you attempt to create a volume set from two or more
|           volumes that already contain files and data, the file system does
|           not issue an error message when you issue the MOUNT/BIND command.
|           However, the volumes are unusable as a volume set because the
|           directory structures are not properly bound.

G.

It depends.   You can't just put files on disparate disks and then, issue a
MOUNT/BIND and expect to see them as one happy family.   The files on ODS-n
disks have a file identifier.   The identifier is composed of three values
which represent the file: <NUM(24bits), SEQ(16 bits), RVN(256 bits).   The
RVN is Relative Volume Number.   If a volume is not bound, the RVN is zero.
If you were to try to /BIND your volumes, the file system would not know
where these files exist.

-- 
VAXman- A Bored Certified VMS Kernel Mode Hacker       VAXman(at)TMESIS(dot)ORG

Well I speak to machines with the voice of humanity.