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 at 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 at centos.org > https://lists.centos.org/mailman/listinfo/centos
On May 27, 2019, at 00:32, Ralf Prengel <ralf.prengel at 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 at 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.
Le 27/05/2019 ? 06:32, Ralf Prengel a ?crit?:> > 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 -- Microlinux - Solutions informatiques durables 7, place de l'?glise - 30730 Montpezat Site : https://www.microlinux.fr Mail : info at microlinux.fr T?l. : 04 66 63 10 32 Mob. : 06 51 80 12 12
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 -- ---- Fred Smith -- fredex at fcshome.stoneham.ma.us ----------------------------- The Lord is like a strong tower. Those who do what is right can run to him for safety. --------------------------- Proverbs 18:10 (niv) -----------------------------
On Mon, May 27, 2019 at 06:32:19AM +0200, Ralf Prengel (ralf.prengel at 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. -- Jobst Schmalenbach A computer without Microsoft is like chocolate cake without ketchup!
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 at 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.... -- ---- Fred Smith -- fredex at fcshome.stoneham.ma.us ----------------------------- "And he will be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace. Of the increase of his government there will be no end. He will reign on David's throne and over his kingdom, establishing and upholding it with justice and righteousness from that time on and forever." ------------------------------- Isaiah 9:7 (niv) ------------------------------
Once upon a time, Jobst Schmalenbach <jobst at 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. -- Chris Adams <linux at cmadams.net>