Hallo,
what is the standard way to sync time under Centos 7. ntp or chrony.
Thanks for a short hint.
Ralf
I more or less depend on NTP and synchronize against my public upstream NTP servers. The only system that runs chrony is my FreeIPA server.
Regards, Ben
On May 26, 2019, at 10:32 PM, Ralf Prengel ralf.prengel@rprengel.de wrote:
Hallo,
what is the standard way to sync time under Centos 7. ntp or chrony.
Thanks for a short hint.
Ralf
CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
On May 27, 2019, at 00:32, Ralf Prengel ralf.prengel@rprengel.de wrote:
what is the standard way to sync time under Centos 7. ntp or chrony.
chrony is the default time sync daemon on C7. ntp is provides but not default.
-- Jonathan Billings
On May 27, 2019, at 07:51, Jonathan Billings billings@negate.org wrote:
ntp is provides but not default.
*Sigh* I mean “provided”. It’s too early.
-- Jonathan Billings
what is the standard way to sync time under Centos 7. ntp or chrony.
chrony syncs to an NTP server, in the same way that ntp syncs to an NTP server. The both work.
I have both ntpd (under CentOS 6) and chronyd (under CentOS 7) NTP servers on my network, they all work fine together.
P.
On Mon, May 27, 2019 at 04:29:28PM +0100, Pete Biggs wrote:
what is the standard way to sync time under Centos 7. ntp or chrony.
chrony syncs to an NTP server, in the same way that ntp syncs to an NTP server. The both work.
I have both ntpd (under CentOS 6) and chronyd (under CentOS 7) NTP servers on my network, they all work fine together.
P.
I used chrony at home, a couple of decades ago (give or take) way back when I was on dialup, because if its ability to serve time to machines that are not always connected.
Since it is now the default NTP provider for EL7 I use it again, and it still works fine for my needs.
Fred
Le 27/05/2019 à 06:32, Ralf Prengel a écrit :
what is the standard way to sync time under Centos 7. ntp or chrony.
Thanks for a short hint.
Chrony is the standard way, but one of the first things I do when installing a CentOS server is replace it with NTP.
Here's a short blog article (in french) about NTP on CentOS.
* https://www.microlinux.fr/centos-7-ntp/
Cheers,
Niki
On Mon, May 27, 2019 at 06:32:19AM +0200, Ralf Prengel (ralf.prengel@rprengel.de) wrote:
Hallo,
what is the standard way to sync time under Centos 7. ntp or chrony.
YMMV.
I have used NTP for many, many years so I am familiar with it and also have ALL config files, I normally just delete chrony and install ntpd, then copy the config files and start ntp. All done, 2 minutes.
Chrony cannot supply time info, so if you have clients requesting time info the server cannot serve time, you need ntpd for that. I have many windows stations that pull time from my CentOS servers.
On Tue, May 28, 2019 at 11:44:35AM +1000, Jobst Schmalenbach wrote:
On Mon, May 27, 2019 at 06:32:19AM +0200, Ralf Prengel (ralf.prengel@rprengel.de) wrote:
Hallo,
what is the standard way to sync time under Centos 7. ntp or chrony.
YMMV.
I have used NTP for many, many years so I am familiar with it and also have ALL config files, I normally just delete chrony and install ntpd, then copy the config files and start ntp. All done, 2 minutes.
Chrony cannot supply time info, so if you have clients requesting time info the server cannot serve time, you need ntpd for that. I have many windows stations that pull time from my CentOS servers.
Back when I used chrony in my home LAN it certainly did serve time. I brought it up on my firewall (an old PC running SmoothWall) as a local time server and it worked great for that purpose.
It's hard to imagine that someone would have REMOVED that ability in the intervening years....
On Mon, May 27, 2019 at 09:50:51PM -0400, Fred Smith (fredex@fcshome.stoneham.ma.us) wrote:
On Tue, May 28, 2019 at 11:44:35AM +1000, Jobst Schmalenbach wrote:
On Mon, May 27, 2019 at 06:32:19AM +0200, Ralf Prengel (ralf.prengel@rprengel.de) wrote:
It's hard to imagine that someone would have REMOVED that ability in the intervening years....
I read a couple of comparisons some time back, I learned chrony cannot server time. The comparison might have been wrong!
I just read this, so I stand corrected:
https://chrony.tuxfamily.org/comparison.html
Once upon a time, Jobst Schmalenbach jobst@barrett.com.au said:
Chrony cannot supply time info, so if you have clients requesting time info the server cannot serve time, you need ntpd for that. I have many windows stations that pull time from my CentOS servers.
That is not correct. In the default config, chrony doesn't serve time, which is a good thing (see: all the problems with ntpd serving a lot more than time). All you have to do is uncomment/add "allow" lines in /etc/chrony.conf.
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