projects / pve-docs.git / blame
| Commit | Line | Data |
|---|---|---|
| 4b985658 FG |
1 | Time Synchronization |
| 2 | -------------------- | |
| 1a2d79d9 DM |
3 | ifdef::wiki[] |
| 4 | :pve-toplevel: | |
| 5 | endif::wiki[] | |
| 4b985658 FG |
6 | |
| 7 | The {pve} cluster stack itself relies heavily on the fact that all | |
| 8 | the nodes have precisely synchronized time. Some other components, | |
| 9 | like Ceph, also refuse to work properly if the local time on nodes is | |
| 10 | not in sync. | |
| 11 | ||
| 12 | Time synchronization between nodes can be achieved with the ``Network | |
| 13 | Time Protocol'' (`NTP`). {pve} uses `systemd-timesyncd` as NTP client | |
| 14 | by default, preconfigured to use a set of public servers. This setup | |
| 15 | works out of the box in most cases. | |
| 16 | ||
| 17 | ||
| 18 | Using Custom NTP Servers | |
| 19 | ~~~~~~~~~~~~~~~~~~~~~~~~ | |
| 20 | ||
| 21 | In some cases, it might be desired to not use the default NTP | |
| 22 | servers. For example, if your {pve} nodes do not have access to the | |
| 23 | public internet (e.g., because of restrictive firewall rules), you | |
| 24 | need to setup local NTP servers and tell `systemd-timesyncd` to use | |
| 25 | them: | |
| 26 | ||
| 27 | .File `/etc/systemd/timesyncd.conf` | |
| 28 | ---- | |
| 29 | [Time] | |
| 5ec2497f | 30 | NTP=ntp1.example.com ntp2.example.com ntp3.example.com ntp4.example.com |
| 4b985658 FG |
31 | ---- |
| 32 | ||
| 33 | After restarting the synchronization service (`systemctl restart | |
| 34 | systemd-timesyncd`) you should verify that your newly configured NTP | |
| 35 | servers are used by checking the journal (`journalctl --since -1h -u | |
| 36 | systemd-timesyncd`): | |
| 37 | ||
| 38 | ---- | |
| 39 | ... | |
| 40 | Oct 07 14:58:36 node1 systemd[1]: Stopping Network Time Synchronization... | |
| 41 | Oct 07 14:58:36 node1 systemd[1]: Starting Network Time Synchronization... | |
| 42 | Oct 07 14:58:36 node1 systemd[1]: Started Network Time Synchronization. | |
| 43 | Oct 07 14:58:36 node1 systemd-timesyncd[13514]: Using NTP server 10.0.0.1:123 (ntp1.example.com). | |
| 44 | Oct 07 14:58:36 nora systemd-timesyncd[13514]: interval/delta/delay/jitter/drift 64s/-0.002s/0.020s/0.000s/-31ppm | |
| 45 | ... | |
| 46 | ---- |