[Info-vax] How to read system time from cluster node

[jbriggs444 at gmail.com]

On Mar 27, 6:45 am, Rogal <michal.rog... at gmail.com> wrote:
> On 26 Mar, 22:01, Michael Austin <maus... at firstdbasource.com> wrote:
>
> > Rogal wrote:
> > > Hello!
>
> > > I've been using VMS for just a few weeks, so this question may be
> > > lame :). I need to write DCL script which compares system time drift
> > > between two nodes in a cluster (VMS 7.3). Is there any method to fetch
> > > system time from another node? I hoped that F$GETSYI would have such
> > > capability but no...
>
> > > thanks in advance
>
> > > MR
>
> > Is there some reason you are not using NTP to keep systems in sync?
>
> NTP is used there  but I need additional control over this - in case
> of failure of some kind. As this machine is a GSM SMS Centre where
> timestamps are critical, I need an alert to be raised when clock skew
> is more than 15-20 seconds.

I would probably use DECnet task to task communications for this.

In your home directory on the target node:
$ create showtime.com
$ open net sys$net /write
$ write net f$cvtime()
$ close net
$ exit
^Z

On the node from which you are checking

$ start_time = f$cvtime()
$ open net target_node::"task=showtime"
$ read net remote_time
$ close net
$ end_time = f$cvtime()
$
$
$! Check that remote_time, start_time and end_time are all within
tolerance of one another.
$! If not, either the monitor has failed or the clocks are out of
synch.

[Syntax not checked -- With eisner gone, I don't have a test platform
to work from.  And if it were my monitoring
script, I'd be working diligently to put some error checking/sanity
checking in there and then I'd be testing the heck out of it]