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