[Info-vax] removing device

[R.A.Omond]

David J Dachtera wrote:
> "R.A.Omond" wrote:
>> Christoph Gartmann wrote:
>>> Hello,
>>>
>>> is it possible to remove a non existent device under OpenVMS 7.3-2?
>>> I have DKC3: which existed once on my SmartArray 5300A. Now that I
>>> reconfigured the controller the device is still present and its error
>>> counter increases over time. I know that a reboot will cure the problem.
>> No, it's not possible (unless you want to be, ahem, "adventurous").
>>
>> Best you can do is: $ set device/noavailable/noerror dkc3:
> 
> Y'know, I think even Hoff tried to explain this to me lo these many
> years ago, but I'm still mystified as to why LTA device, LD devices, TN
> devices and others can come and go at will, but some DCBs are
> "permanent" and can't be deleted.

Well, it's clearly possible for device drivers to delete DCBs
that are no longer in use.  You'll notice that the devices you
quote are all "transient" in nature (i.e. it's expected that
they'll come-and-go quite rapidly in the normal running of the
system).  So it's quite beneficial (and some would say essential)
that the device driver deletes not-in-use DCBs, to prevent the
system from exhausting real non-paged memory.  Disk and tape
devices are different in the sense that it's rather unusual
for there to be a device that "disappears" during the up-time
of the system.  Hence drivers for such devices were not written
to add the complexity of dealing with such a situation.

How much more complex this is to add extremely seldom used
functionality, I don't know off-hand.

That's the way I understand it.