[9fans] Keeping a Plan9 domain's time consistent

[Lucio de Re lucio@proxima.alt.za]

According to G. David Butler:
> 
> I've started thinking about how to keep time consistent
> in a Plan9 system.  This is one problem that is common
> with most distributed systems.
> 
You bet!  I keep having to rewind the clock on my file server because 
it foolishly believes it is running on sensible hardware :-(

> We could use timed between the file servers and increase
> the frequency of the cpu/terminal systems syncing their
> time using the existing stat of /.  This would keep the
> overhead of the timed protocol down.
> 
I run a silly combination of NTP and timed amongst some six hosts, and 
the result seem surprisingly good (this on NetBSD - the NT boxes aren't 
yet synced, although SAMBA would take care of that, I believe).  I'd 
love to do better though, and the Plan 9 docs hint that it may be 
possible, where they suggest that Bell Labs use an external source for 
their time.

> Or we could run ntp on the auth server and slave all the
> other systems from that.
> 
The NTP docs argue that timed and ntp should not run on the same host, 
but I could find no good reason, nor a practical alternative.  I'd love 
this issue to be clarified.

++L