[kwlug-disc] Unexpected find of time syncing among hosts in Netdata

[L.D. Paniak]

Time sync is very important for clustered services. 
A ceph cluster I tend has NTP running on all systems in the cluster. 
They sync to a trio of local stratum 1 systems that each have a GPS
sensor. This setup keeps clocks in the cluster to within 25ms of each other.
Public NTP is not going to give you much better than 100ms accuracy.

chrony is a promising replacement for ntp:
https://engineering.fb.com/2020/03/18/production-engineering/ntp-service/

High performance cluster applications (eg. MPI), typically take care of
their own synchronization down to microseconds:
https://mpitutorial.com/tutorials/mpi-broadcast-and-collective-communication/


On 12/26/20 12:01 PM, Mikalai Birukou via kwlug-disc wrote:
> Netdata can stream metrics from some hosts (slaves) to others
> (masters), and respective configuration file /etc/netdata/stream.conf
> has the following in section [stream]:
>
> ```
>
> [stream]
>     ...
>
>
>     # Attempt to sync the clock the of the master with the clock of the
>     # slave for that many iterations, when starting.
>     initial clock resync iterations = 60
>
> ```
>
> Nice idea, when you never thought about clock syncing. What actual
> tools proper tools are used in a bunch of physical machines. Master
> time server?
>
>
> _______________________________________________
> kwlug-disc mailing list
> kwlug-disc at kwlug.org
> https://kwlug.org/mailman/listinfo/kwlug-disc_kwlug.org

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: OpenPGP digital signature
URL: <http://kwlug.org/pipermail/kwlug-disc_kwlug.org/attachments/20201226/f60bb3af/attachment.sig>