[HECnet] Uptime

[Johnny Billquist]

Wonderful! This kind of information is what really makes my day. :-)

   Johnny

On 2018-02-08 08:55, Johnny Eriksson wrote:
> One of my nodes fell off Hecnet (actually a while ago).
> 
> I finally got around to reboot it in order to get it back.
> 
> The problem?  Too much uptime.
> 
>    Monitor Atle - DEC-10 at work
>    System uptime 10483:52:41
>    Current date/time Thursday 8-Feb-2018 8:00:14
> 
> Thats what you get for running stable hardware.  On the other hand,
> this is/was a known problem:
> 
>    MCO: 12935          Name: WXD               Date: 22-May-86:14:12:35
> 
>    [Symptom]
>    DECnet stops working correctly.  The -10 sees all the nodes
>    on the ethernet, but isn't seen by any of the nodes.
> 
>    [Diagnosis]
>    The -10 has stopped sending ethernet hello messages.  This
>    is caused by the -10 getting an overflow when calculating the DECnet
>    time (milliseconds of uptime), which is then used to determine when
>    to send the next message.  The algorithm is:
> 	  MOVE    T1,SYSUPT
> 	  IMULI   T1,1000.
> 	  IDIVI   T1,JIFSEC
>    This overflows at 159 hours, 4 minutes, 22 seconds, and 19. ticks (60hz).
> 
>    [Cure]
>    Change IMULI -> MULI, and IDIVI -> DIVI
> 
>    This algorithm won't overflow until 9544 hours of uptime (395+ days).
> 
> --Johnny (the other one)
> 
>    /\_/\
>   ( *.* )
>    > ^ <
> 

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol