topic Re: DGA DKA DSA acronyms in Operating System - OpenVMS

DGA DKA DSA acronyms

Rasmus_3 — Tue, 01 Nov 2005 11:29:24 GMT

What do the acronyms DGA, DGB, DKA, and DSA stand for?

Cheers

Rasmus

Re: DGA DKA DSA acronyms

Ian Miller. — Tue, 01 Nov 2005 11:34:35 GMT

DSA was digital storage architecture

If you mean VMS device names then its
Dxy
D for disk
x=G for fibre channel, K for SCSI, I for DSSI etc
y=A,B,C, indicates which bus (unless port allocation classes are in use).

Re: DGA DKA DSA acronyms

Jan van den Ende — Tue, 01 Nov 2005 11:58:01 GMT

To extend that:

DS means D for Disk, S for Shadow; so DS devices are ShadowSets.

DR used to be Massbuss, but nowadays usually is is Digital RAID

DU is varius DSA-compliant drives, (as is DI)

DV is floppy drive, DQ is IDE drive (floppy or CD)

There might well be others still..

Proost.

Have one on me.

jpe

Re: DGA DKA DSA acronyms

John Gillings — Tue, 01 Nov 2005 18:17:38 GMT

Generalising a bit more to the OpenVMS device naming scheme...

it's usually written as:

ddcu

where "dd" is the device type prefix. 2 letters and registered with a central naming authority. Disk devices usually start with "D". There are many different prefixes. I can say for certain that all of DA, DB, DF, DG, DI, DJ, DK, DL, DP, DQ, DR, DS DU and DV have been used at some time.

They are not acronyms as such, just a code used by drivers to identify different disk types & controler technologies.

The next letter "c" is the controller "A" to "Z", allocated sequentially as the system finds them. Finally the unit number "u", generally 0 through 9999, but some devices have extended the range.

You'll find other device names, and classes of device name. For example those starting with "E" are generally ethernet devices EI, ES, EW, EX,... There are also mailboxes starting with "MB", terminals TN, TT, TX and tape devices MD, MK, MU (I think it's "M" for "Magnetic Tape").

Although the naming scheme is *reasonably* consistent, there are always exceptions to any rule you can glean from looking at SHOW DEVICE. Don't try to read too much into it. A good place to find out about devices is the documentation for the $GETDVI system service.

Re: DGA DKA DSA acronyms

Martin Vorlaender — Wed, 02 Nov 2005 03:31:02 GMT

As a side note:

I always liked Inforserver devices the best: DAD and MAD :-)

cu,
Martin

Re: DGA DKA DSA acronyms

Stanley F Quayle — Wed, 02 Nov 2005 09:22:10 GMT

Actually, all combinations from DA through DZ have been used. I discovered that when asking VMS Engineering about what USB disk drives will come up as (when they're supported).

It's also possible to encounter "disks" that use the LD and VD virtual disk drivers, which don't come up as a "D" anything.

Re: DGA DKA DSA acronyms

Rasmus_3 — Wed, 02 Nov 2005 10:14:34 GMT

But I don't really get how my Stripe sets show up as DGA.

//Rasmus

Re: DGA DKA DSA acronyms

Martin Vorlaender — Wed, 02 Nov 2005 10:46:38 GMT

Most probably, striping is done by the FC controller. OpenVMS knows nothing of that, for OpenVMS, these are just FC disks - thus DGA.

cu,
Martin

Re: DGA DKA DSA acronyms

Rasmus_3 — Wed, 02 Nov 2005 11:31:48 GMT

Thank you all!

Re: DGA DKA DSA acronyms

Stanley F Quayle — Wed, 02 Nov 2005 11:57:15 GMT

How about assigning points to us for helping?