[Info-vax] Security, support and VMS, was: Re: A new VMS?

[Arne Vajhøj]

On 5/5/2021 12:06 AM, Tad Winters wrote:
> On 5/4/2021 9:53 AM, Bill Gunshannon via Info-vax wrote:
>> On 5/4/21 9:25 AM, Phillip Helbig (undress to reply) wrote:
>>> In article <ifcu1jFphjgU1 at mid.individual.net>, Bill Gunshannon
>>> <bill.gunshannon at gmail.com> writes:
>>>> What "functionality" does VMS have that Unix and Windows don't?
>>>>
>>>> Remember, we are talking "functionality", not just doing something
>>>> in a different manner.
>>>
>>> Trivially, any Turing machine can emulate another, so they all have the
>>> same functionality.  As for usefulness, top of the list for VMS are
>>> logical names, clustering, fine-grained security concept, HBVS, and file
>>> versions.
>>
>> All of them exist in some form in Unix except file versions and I have
>> never known anyone other than VMS users who saw value in them. Sorry.
> 
> Where I work, and they don't have VMS, someone says we're going to
> perform a DR test by "virtually" pulling the power on one site.  The
> response is, "Wait, the active nodes of the cluster are at that site.  I
> need to fail them over to the other side before you pull the power."
> 
> "Active?"  The "other side?"  How is that a cluster?  Where's the DR in
> that?

I cannot follow your post.

Clusters exist in loadsharing (active/active) and failover
(active/passive) flavors.

Non-persisting nodes are practically always loadsharing.

Persisting nodes can be loadsharing or failover depending on
specific needs and software/hardware capability.

But even in a loadsharing config you may chose not to loadshare
between data centers. The feasibility of that depends
on the distance between them. If it is like 3 miles
then no problem, but if it like 3000 miles then it just
won't perform due to the latency.

It does not matter what cluster software it is. The
speed of light is a hard limit.

And the R in DR stands for Recovery, so DR does not imply
no downtime. The time it takes to recover is called RTO.
I can obviously be zero, but  is not required to.

Arne