mixed-version cluster

[Ron Maillet]

I have a customer that has a 4-node cluster.
2 VAXes are running VMS 6.2.
2 Alphas are running VMS 7.3-1.

The customer wants to upgrade the Alphas from 7.3-1 to 7.3-2 using separate system disks, using the rolling upgrade, while the VAXes stay up (6.2).

If the upgrade "rolls" there would be a point where there would be 3 versions of VMS. I seem to have read somewhere where you cannot have more than 2 versions ever, even through rolling upgrades. Is this true?

thanks...

-Ron Maillet-
VMS Support

[Jan van den Ende]

Ron,

since Vax versions are not always synchronous ty AXP versions, such 3-version situations are inevitable (there only exists Vax 7.3, no sub-versions).
That said, I have serious doubts about any 6.2 <-> 7.3(-x) combination, but you ARE already running that.

But, there is a _WIDE_ gray area between "supported" and "may work".
Since you already ARE running Vax6.2 plus Alpha7.3-x, there definitely is _NO_ code that forbids it.
So, your chances are good, but, _IF_ things go wrong, you ARE on your own!

Should you decide to do it, will you report back here?

Success!

Proost.

Have one on me.

jpe

[Karl Rohwedder]

Since this combination is unsupported, be sure your backup is o.k.!

regards Kalle

[Kris Clippeleyr]

Ron,
I'm not sure of the combination VAX 6.2 and Alpha 7.3-2, but from my own experience the combination VAX 7.3, Alpha 7.3-2 (or 8.2) and IA64 8.2-1 hasn't given any trouble up till now. I wouldn't recommend it though in a production environment.
Greetz,
Kris (aka Qkcl)

[Ian Miller.]

It should be fine. Probably not supported.

[Donald Hill]

Ron
We also have a mixed cluster- currently a 9 member cluster made up of a mix of VAX, Alpha and occasionally a I64 machines. We currently run VAX 7.3 with a mix of Alpha 7.3-1, 7.3-2 and now 8.2, and we occasionally bring in a VAX 6.2 or a I64. We have been running this type of configuration for many years with no problems. We are using it in a development/ test arrangement - not production.

Don Hill