TIME SNTP with hosts for VM

[CERKYR]

Hello,

Between, the VM and my laptop, I have around 11 seconds for the TIME.

I consider that my laptop have the good time.

First, do you have an atomic clock web site ?

Second, it's like my VMs adn the hosts loose some seconds to synchronize the time.

Regards,

[daphnissov]

This is why you point all your devices to an internal NTP server. It's fine to use an external NTP server as the upstream time source, but having local time in sync is imperative.

[CERKYR]

Hello,

In fact, all our ESXi server must be updated from 3 external NTP servers.
Now, the goal is to check inside the 3 SHELLs of the ESXi  .

How to do this ?

Regards,

[CERKYR]

in the shell

cat /etc/ntp.conf

> here I can see my 3 NTP server IP address

ntpq -p

> I receive some values, but how to be sure that the synchronisation is done ?

[daphnissov]

You don't need to do it from shell, you do it from the ESXi host client.

[CERKYR]

Yes, you are right.

But I have a doubt.
And there is a problem.

--
I need to clarify our "server map".
We are in a VLAN outside the rest of the work except for some protocol like SNTP (123).
But only for the VCSA. (vcenter)
The ESXi server are not connected with the rest of the world.

We must open a console to VCSA to manage our ESXi server, and VM too.
It just to secure everything.

-
Then our VCSA is able to synchronise with ou SNTP server in the rest of the world.
Then, our ESXi are configured to synchronise with the VCSA : it doesn't work. (command ntpq -P  in the shell)
Then, our VMware tools are configured to synchronize with the hosts (ESXi).

[daphnissov]

Firstly, the protocol is NTP which operates over UDP 123. SNTP is a variation on NTP and not a separate thing altogether. Secondly, ESXi cannot take its time from vCenter, so you will need to open the necessary ports so each ESXi host can get its time from a relevant NTP server. Third, you will need to point those ESXi hosts at this NTP server and not at vCenter Server.

[CERKYR]

"ESXi cannot take its time from vCenter"

Why ?

[daphnissov]

Because vCenter cannot be a time server.