[Info-vax] Distributed and Clustered App Design (was: Re: WHY IS VSI REQUIRING A HYPERVISOR FOR X86 OPENVMS?)

[Simon Clubley]

On 2021-01-04, Stephen Hoffman <seaohveh at hoffmanlabs.invalid> wrote:
> On 2021-01-04 18:17:29 +0000, Simon Clubley said:
>
>> So it's the same as always in that you also need the additional 
>> supporting infrastructure to provide what you get as standard with VMS 
>> clustering, including being able to detect when a node has only 
>> temporarily failed (in order to prevent everything that comes with that 
>> situation) when that temporarily failed node comes back online.
>
> I did a presentation on this topic way back 'round Y2K at a DECUS symposium.
>
> It's rather more involved than the lock manager?electing a primary is a 
> piece of this, certainly.
>

I know about at least some of the alternatives, especially ZooKeeper
and the components that use it.

My point was that I was surprised to see Jan-Erik suggest that a SAN
distributed over multiple sites could by itself be an alternative to
a VMS cluster because I couldn't see how that could be possible without
all the other bits that VMS clustering provides and which are required.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
Walking destinations on a map are further away than they appear.