[Info-vax] Unpleasant Disk Shadowing Surprise

[Robert A. Brooks]

On 10/12/2011 1:42 PM, abrsvc wrote:

> In a host based shadowing scenerio, a failure of a member WILL NOT
> cause the entire DSA device to enter mount verification.

Yeah, it will.  You're wrong.

Any I/O that completes with an (appropriate) error status will cause the 
virtual unit to enter mount verification.

For a shadow set, there is no concept of a single member entering mount 
verification.  It's the virtual unit that enters mount verification. 
The details of what exactly happens on a per-member basis
are similar to that of a non-shadowed device, but it's HBVS that 
controls the virtual unit entering and exiting mount verification.

As mentioned earlier, all I/O to the virtual unit is queued up until 
mount verification exits (for whatever reason).

For those with the sources, see [SHADOWING]SHD_VP.MAR for the details

                         -- Rob