topic Query: OPA0: unit timed out in Operating System - OpenVMS

OPA0: unit timed out

VMSuser — Tue, 29 Apr 2025 08:02:17 GMT

I have a VAX 4000-90 system. I notice the error count on the OPA0: keeps increasing whenever the device is allocated and then deallocated (when system manager has logged into the console and then logs out). I also notice that the device is timed out:

====

STPROA $ sh device/full opa0

Terminal OPA0:, device type LA36, is online, unit timed out, record-oriented
device, carriage control, error logging is enabled.

Error count 24 Operations completed 13619
Owner process "" Owner UIC [SYSTEM]
Owner process ID 00000000 Dev Prot S:RWLP,O:,G:,W:
Reference count 0 Default buffer size 132

STPROA $

======

I also notice that whenever I allocate OPA0: from another interactive session, and leave it allocated to myself (when no one is logged into the console), the error count stops increasing. Until I deallocate the device. At which point, the error count increases by 1. And then the error count keeps increasing until either I allocate the OPA0: device again, or someone else logs into the console, and stays logged into the console.

Has anyone seen this before? Is there a console patch available in VMS or console firmware available to fix this? The VAX 4000-90 is running VAX/VMS 5.5-2. I have another VAX 4000-90 running VAX/VMS 5.5-2H4, and the OPA0: device there does not have this problem. So I'm wondering if 5.5-2H4 is a possible fix.

Thanks in advance.

- Ron Beasley (~~**personal info erased**~~)

Re: OPA0: unit timed out

Steven Schweda — Tue, 29 Apr 2025 06:14:34 GMT

> [...] the error count on the OPA0: keeps increasing [...]

Rate? Who's doing the I/O which gets the error? And you care
because...?

> Terminal OPA0:, device type LA36, [...]

What is it _really_?

> Has anyone seen this before? [...]

Not I, but I seldom use my hardware VAXes these days, and I'd be
unlikely to look at the error count on the console terminal when I do.
My VAX console tends to be an xterm on a Mac, with an ssh connection to
an IA64 system (rx2600, VMS V8.4-2L3), and a SET HOST /LAT connection
through a DECserver 90 to the physical console port on the VAX (4000
model 200, MicroVAX 3200?). Might be different from your arrangement.

> [...] Is there a console patch available in VMS or console firmware
> available to fix this? [...]

I know nothing, but I doubt it. My guess at blame assignment would
be something you're doing, not a hardware/firmware problem.

> [...] the OPA0: device there does not have this problem. [...]

Is the (non-OS) software identical? Used identically?

> [...] So I'm wondering if 5.5-2H4 is a possible fix.

Again, I doubt it. As I recall, -2H4 was a hardware-support
release (hence the "H"); I wouldn't bet that there were functional
changes. (But it should be a harmless upgrade from plain -2, if you're
looking for an experiment to run.)

Query: OPA0: unit timed out

support_s — Thu, 08 May 2025 07:18:20 GMT

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