Dirk Munk
2017-02-03 23:19:55 UTC
There have some discussions about exact timekeeping in the group lately.
For me the merits of exact timekeeping have been clear for decades. If
you are working in an environment where chains of computer systems are
passing information to each other, or where they are connected to
network devices, firewalls etc., then transactions, events, and other
things will have a timestamp attached to them. If there is some kind of
a problem in such a surrounding, then it is very important that you have
accurate timestamps to rely on, it is the only way you can analyse the
sequence of events with certainty.
For me it is self-evident that all devices in a network should have the
exact time, running an NTP client on every device is the best way to
achieve that.
Of course you can configure every server in such a way that it will get
its time from the internet. But then you may worry about malware getting
into your server over the NTP IP port (UDP or TCP). In that case you
might want to install your own NTP server with a GPS receiver. In fact
it is recommended that you have at least three time servers, and if you
have a big organization with enough cash, then that would be the best
thing to do. Three NTP servers on three different locations. Of course
there are other ways to implement an NTP infrastructure on your network
as well, it just requires a bit of thinking.
For some odd reason Microsoft never implemented the standard NTP
client/server program. The result is that Windows systems are often many
seconds out of sync, even if they have the SNTP client running.
However there is a real NTP client/server program based on the sources
from ntp.org available from the German GPS clock manufacturer Meinberg.
You can get it here:
https://www.meinbergglobal.com/english/sw/ntp.htm
I’ve been using it for years on Windows systems. The present version is
based on the current 4.2.8p9 sources from ntp.org. It seems the VMS NTP
stack is also based on the sources from ntp.org, perhaps some one can
check which version it is at present?
Meinberg produces a range of NTP/PTP GPS clocks and they also have a
PTPv2 interface card. It is used for nothing else as the PTP protocol,
so it can not be used as a network interface card. Since VSI is looking
at PTP, perhaps this can be a solution.
For me the merits of exact timekeeping have been clear for decades. If
you are working in an environment where chains of computer systems are
passing information to each other, or where they are connected to
network devices, firewalls etc., then transactions, events, and other
things will have a timestamp attached to them. If there is some kind of
a problem in such a surrounding, then it is very important that you have
accurate timestamps to rely on, it is the only way you can analyse the
sequence of events with certainty.
For me it is self-evident that all devices in a network should have the
exact time, running an NTP client on every device is the best way to
achieve that.
Of course you can configure every server in such a way that it will get
its time from the internet. But then you may worry about malware getting
into your server over the NTP IP port (UDP or TCP). In that case you
might want to install your own NTP server with a GPS receiver. In fact
it is recommended that you have at least three time servers, and if you
have a big organization with enough cash, then that would be the best
thing to do. Three NTP servers on three different locations. Of course
there are other ways to implement an NTP infrastructure on your network
as well, it just requires a bit of thinking.
For some odd reason Microsoft never implemented the standard NTP
client/server program. The result is that Windows systems are often many
seconds out of sync, even if they have the SNTP client running.
However there is a real NTP client/server program based on the sources
from ntp.org available from the German GPS clock manufacturer Meinberg.
You can get it here:
https://www.meinbergglobal.com/english/sw/ntp.htm
I’ve been using it for years on Windows systems. The present version is
based on the current 4.2.8p9 sources from ntp.org. It seems the VMS NTP
stack is also based on the sources from ntp.org, perhaps some one can
check which version it is at present?
Meinberg produces a range of NTP/PTP GPS clocks and they also have a
PTPv2 interface card. It is used for nothing else as the PTP protocol,
so it can not be used as a network interface card. Since VSI is looking
at PTP, perhaps this can be a solution.