[Info-vax] V/I64 R/W USB mass storage boot support?

[Jeremy Begg]

Rod,

> I was hoping to be able to use the booted USB mass storage device
> in R/W mode if possible.
> 
> If someone with deeper knowledge of the OpenVMS USB driver indicated
> that
> functionality is doomed to fail, then I can explore alternatives.

I too have successfully booted my rx2600 from a USB stick but I have not 
tried to run VMS from it.  (By "run" I mean do things other than those 
provided by the OpenVMS installation DVD menu.)

There's no problem writing to these devices from VMS in the usual way (e.g. 
BACKUP/IMAGE or other RMS file I/O) but I think the VMS kernel uses a 
different code path for writing errorlog buffers and the system crashdump 
file.  It wouldn't surprise me if that code path made various assumptions 
about the device it was writing to.  Hence the failure when you tried to 
shut down the system.  Given that you were then unable to boot from the USB 
stick I would guess that the shutdown failure caused the USB stick to get 
confused about the I/O states.

I wouldn't expect VMS to support USB for anything other than booting a clone 
of the installation DVD and performing operations under the "single-user" 
mode that is provided by that DVD.  Which caters for most situations except 
when network access of some sort would be handy.

Regards,

	Jeremy Begg