[Info-vax] Programming languages on VMS

[Arne Vajhøj]

On 2/1/2018 7:56 PM, Bill Gunshannon wrote:
> On 02/01/2018 07:47 PM, Arne Vajhøj wrote:
>> On 2/1/2018 7:24 PM, Bill Gunshannon wrote:
>>> On 02/01/2018 07:08 PM, Arne Vajhøj wrote:
>>>> On 2/1/2018 6:22 PM, Bill Gunshannon wrote:
>>>>> On 02/01/2018 06:00 PM, Jan-Erik Soderholm wrote:
>>>>>> Well, if you do have a system, I guess you do also have someone
>>>>>> to fix small issues or someone to call in. Note that a failed
>>>>>> disk in a mirror-set is not that urgent, in particular if it
>>>>>> is an 3-disk mirror set. It is not a show-stopper and you
>>>>>> can get it fixed at office times.
>>>>>
>>>>> But that was my point exactly.  It would take someone familiar with
>>>>> not only VMS but the hardware that VMS runs on, which is not PC
>>>>> class hardware.
>>>>
>>>> You don't think a normal bright guy can pull out a hot swapable
>>>> disk and put another one in?
>>>
>>> Possibly.  But what about the commands needed to integrate the new
>>> disk into the shadow set?  I have admined numerous VMS systems as
>>> well as more than a dozen other OSes and I couldn't do it without
>>> the documentation.
>>
>> I most admit that I have zero experience with software/host
>> based mirror.
>>
>> Maybe that is a problem.
>>
>> If it was hardware based mirror, then it would just work.
> 
> Even hardware  mirroring is not always as simple as you seem to
> think.  I have had numerous systems where in order to "fix" a
> RAID Array the whole system had to be taken out of service for
> some rather ridiculous lengths of time. (This the reason my
> strategy at the University in the latter years was mirroring
> systems so that the entire data array could be replaced while
> a broken system was repaired.)

I must have been lucky with my green and blue SW then.

:-)

Arne