Feature: Time Sync Configuration

Configure which NTP servers the the local machine will sync its time with.

Notes

• The admin should be able to change the NTP server used for time syncing.
• Cockpit can already enable/disable NTP.
• Our current NTP features are all timedated based. Configuring non-systemd related time syncing is out of scope.
• Configuring an NTP server is out of scope.
• Checking or otherwise validating servers is out of scope.

Stories

Sue is an admin at a law firm. She maintains several servers. Because of company policy, servers can not connect to machines outside the firewall. Sue needs to configure the servers to also try a local NTP server.

Workflows

Sue:

• Logs into Cockpit
• Chooses the server in question
• On the server main page, brings up a dialog with NTP settings
• She types the address of the local NTP server, and saves her changes.

Implementation Notes and Technical Limitations

• Our current server page in general is systemd based. The NTP stuff should follow that lead.
  • Someone could step up and make a non-systemd based server page, but that's out of scope.
• man timesyncd.conf
• Suggest placing files in /etc/systemd/timesyncd.conf.d/*.conf as a way to perform configuration.
• systemd-timesyncd does not have a easy way to say "use exactly these servers and no others". Without reading and modifying all configuration sources of NTP servers, we can only offer "also try these servers and don't use the fallbacks or your builtin defaults".

Prior art

• vSphere: http://www.packet6.com/wp-content/uploads/2014/06/04-vsphere-ntp-servers.png
• CentOS5: http://www.centos.org/docs/5/html/Deployment_Guide-en-US/images/rhl-common/dateconfig/date-time-ntp.png
• Windows: http://www.satsignal.eu/ntp/ntp-setup-H1.png

Feedback

Please give feedback on the above! This is the place where those not working on the feature can provide insight, questions, limitations, notes etc.

• It's usually not only one, but several NTP servers for redundancy and accuracy - andreasn
• Say you have 3 NTP servers set up by default. Do you plain get rid of those, or does the config files have a sense of "Default" vs. "Custom"?