[Info-vax] The dangers of extended uptime. Was: Re: swap and page files

[Stephen Hoffman]

On 2013-01-03 19:41:39 +0000, Phillip Helbig---undress to reply said:

> In article <kc4l71$gai$1 at dont-email.me>, Stephen Hoffman
> <seaohveh at hoffmanlabs.invalid> writes:
> 
>> Alpha loads AlphaBIOS, which gets you nowhere with booting VMS.
> 
> That is the case on the PWS.  Didn't older ALPHAs always boot properly, 
> even without a battery?

AFAIK, no.  When the NVRAM loses its brains, it loses the console type 
setting, and when it loses the console setting, the console program 
finds a zero, and when you find a zero in the console type setting, you 
get AlphaBIOS and when you get AlphaBIOS you get no OpenVMS bootstrap.  
Which is not one of the better designs, IMO.  It'd have been better to 
have failed into a "help me" mode, and not into a a mode that's 
indistingushable from a valid console set-up.

>> VAX prompts for the time.  Or boots with a wacky time on older versions, IIRC.
>> Haven't encountered a dead battery in an Itanium.  Yet.
> 
> Isn't there a timeout after which it stops asking for the time?

If there's a bogus time or other related bogus setting, I'd hope the 
console would stay stuck, and AFAIK it does.

There are settings to suppress the time prompts, but I've not seen 
those applied here, nor would I suggest trying that, given getting 
weird dates associated with stuff can cause — for instance — CMS to 
lock out library access.

My general philosophical preference for unrecognized or weird errors is 
to generate diagnostics where possible and exit quickly when something 
goes wrong or goes weird, and let the human sort things out.    
Recovery from weird or unknown errors is perilous at best.    There are 
more general cases — not involving the BB_WATCH or the TOY used for the 
system time — where generating diagnostics is difficult or infeasible, 
such as low-level and out-of-quota failures in the image activator.  
But I digress.

With VAX, I don't know all of what would happen — those old VAX 
consoles varied a whole lot more than did the Alpha and EFI consoles — 
beyond the boostrap time prompting that would usually ensue when a 
weird time was encountered.  (VAX didn't store a useful time value in 
the TOY clock, so it depended on the TOY value and a value retrieved 
from the system image to generate the actual system time, which led to 
decades of weirdness.)

If you have an old box around, pull the battery and try it.


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