You can try by making the stgpools itself readonly. Backup will fail,
but restore is possible.
Make sure you migrate before making the tape stgpool readonly ;-)

maxnummp=0 will not help, then you can backup to disk, but can't
restore from tape.

- Update all primary stgpools to readonly
- backup stgpools
- Update all primary stgpools to readwrite for the stgpools in the "next"
- Migrate
- Update those stgpools to readonly again.
- Rest of what you want
- Update all stgpools to readwrite


Good Luck,
Maurice



2010/11/8 Steve Roder <spr AT buffalo DOT edu>:
> Perhaps marking all the storage pool volumes R/O would do it (just check
> for any already R/O volumes first).
>
> On 11/8/2010 2:59 PM, Richard Sims wrote:
>>
>> The only way I know to do that is 'UPDate Node ... MAXNUMMP=0' for the
>> duration of that restrictive window.
>>
>>    Richard Sims
>>
>>
>>
>