Does DFO Support

[Douglass Anderson]

Does HP DFO support Multipath devices
on VMS 7.3.1 ?

[Craig A Berry · Accepted solution]

The SPD says that if VMS supports it then DFO supports it:

http://h18000.www1.hp.com/info/SP5585/SP5585PF.PDF

I don't have personal experience using it with multipath, however.

[Robert Brooks_1]

Hi,

I'm curious about your question -- do you have a reason to think there might be some problem with the multipath/DFO interaction, or is your question just standard system management paranoia -- I ask that as a 16-year system manager prior to joining VMS Engineering!

As one who works on multipath, I'd be shocked if there was any issue between DFO and multipath; I've never heard any complaints nor has DFO Engineering ever raised any issues to us.

The *only* way that there would be a problem was if DFO was ***NOT*** using the movefile QIO primitive and was attemting to send I/O directly to a device, bypassing QIO.
The way to do that would be if DFO was creating its own IRPs and sending them directly to the relevant disk driver, rather than doing I/O via QIO.

As movefile was first supported in VAX/VMS V5.4-1 (I think), and DFO was released around then or later, it's pretty safe to assume that DFO is using movefile.

If there was a problem, we'd have heard about it a long time ago; multipath was first supported in OpenVMS Alpha V7.2.

So, my response is ***NOT*** to be taken as an official statement; only product management can issue those, but what I've written above can be taken as a somewhat well-educated guess.

-- Rob (Multipath wonk)

[Wim Van den Wyngaert]

Using it for years. No problems.

Wim

[Kris Clippeleyr]

Hi,

We have a cluster over here running 7.3-1, and DFO, that is equipped with multipath devices. No problems seen.
Just my 2 cents.
Kris (aka Qkcl)

Btw, having trouble posting (error in submit, or something like that).

[Douglass Anderson]

found answer