On 04/21/2017 06:03 AM, Robert Moskowitz wrote: > Fellow armv7-without-rtc-battery users. Maybe you have already learned > this, but I THINK I have completed my education on this thanks to > Miroslav Lichvar on the Chrony list. > > There are two issues here: It takes time for chronyd to set the system > time. And if it fails to reach the ntp servers, well, it failed to set > the time. > > For the first, we need to delay some services from starting until > chronyd is successful. Postfix is one of them. So we need the > following commands: > > systemctl enable chrony-wait > systemctl start chrony-wait > sed -i '/^After=/ s/$/ time-sync.target/w /dev/stdout' > /usr/lib/systemd/system/postfix.service > You're not going to want to do this here. Because systemd has a concept of overrides, administrator modifications should go in /etc/systemd/system, rather than directly modifying /usr/lib/systemd/* files. This will keep your changes across updates. > There are some possible instances where you also want to do this to > httpd.service, but I have been advised on the postfix list NOT to run > postfix if the systemtime is earlier than the postfix build date > > $ postconf -dh mail_release_date > 20130622 > > Plus the postfix.service runs aliases.db which will mess up your > aliases.db timestamp. > > Next there is that pesky issue about what if no ntp servers reached? > > First: > > cat <<EOF>/etc/sysconfig/chronyd || exit 1 > OPTIONS=" -s" > EOF > > Since Centos7 has Chronyd 2.1.1, not 2.2, we have extra work to do in > chronyd.conf: > > cat <<EOF>>/etc/chrony.conf || exit 1 > rtcdevice /dev/doesnotexist > EOF > > > I am adding this to my basic server howto page. > > > _______________________________________________ > Arm-dev mailing list > Arm-dev at centos.org > https://lists.centos.org/mailman/listinfo/arm-dev -- Jim Perrin The CentOS Project | http://www.centos.org twitter: @BitIntegrity | GPG Key: FA09AD77