[Info-vax] free shell accounts?

[John E. Malmberg]

On 1/23/2015 7:03 AM, Stan Radford wrote:
>
> On 2015-01-22, David Froble <davef at tsoft-inc.com> wrote:
>>
>> Simple case:
>>
>> Node A with one disk
>> Node B with one disk
>>
>> HBVS (host based volume shadowing) is used to make both of the disks a
>> single shadow set.  Thus, what's on one disk is also on the other disk.
>>
>> Node B leaves the cluster.  Node A still sees what is on the disk.
 >
 > Ok, now you're talking! Is this what deathrow was doing?
 > And is this done in close to real time? Sounds good!

I do not think Deathrow is using shadowing.

High availability clusters use either host based shadowing or SAN based 
volume replication so that there is no single point of failure.

Can someone find a link to the video on youtube of the HP failover 
demonstration?

A cheap cluster simply allows some systems to provide disk volumes to 
other systems.  If the system serving the disk goes down, that storage 
is gone for the entire cluster.

I have never seen a configuration were only a partial volume was served, 
and I do not think that software stripe sets will allow it.
If it were configured that way.

A hobbyist configuration could be:
    SimH/VAX with VMS 7.3 serving volumes on SATA disk drives
    over the network, Since it is emulated, you can use 10GB Ethernet.

    A real VAX or Alpha or Itanium that it is too expensive to get disks
    for as disk-less clients.

That would not be high availability.

Regards,
-John
wb8tyw at qsl.network
Personal Opinion Only