[Info-vax] Best way to get what I can off a failed VMS Disk?

[geze...@rlgsc.com]

On Saturday, October 24, 2020 at 2:11:24 PM UTC-4, Simon Clubley wrote:
> On 2020-10-24, Phillip Helbig (undress to reply) <hel... at asclothestro.multivax.de> wrote: 
> > In article <rn1ids$78o$1... at panix2.panix.com>, klu... at panix.com (Scott 
> > Dorsey) writes: 
> > 
> >> Get a drive image as soon as possible. You can do it on the Alpha, you 
> >> can pull it off and put it on a PC with Clonezilla or with dd, although 
> >> the best thing to do is to drop it into one of the offline disk duplicators. 
> > 
> > Would forming a shadow set be slower than an offline disk duplicator? 
> >
> Will forming a shadow set cause random I/O all over the failing 
> disk or will the disk be read exactly once from start to finish 
> in strict sequential order without any additional I/Os ? 
> 
> Lots of extra random I/O is very bad on a failing disk. 
> 
> Simon. 
> 
> -- 
> Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP 
> Walking destinations on a map are further away than they appear.
Phillip and Simon,

SHADOW copies are probably not a good idea.

For a start, one must be able to MOUNT the disk to do create a shadow set.

What is wanted is something that needs the least validity from the problematic drive. That is BACKUP/PHYSICAL, a block-by-copy, ignoring the file structure.

- Bob Gezelter, http://www.rlgsc.com