chrony 时间同步软件介绍

[root@kvm ~]# yum install chrony[root@kvm ~]# rpm -ql chrony/etc/NetworkManager/dispatcher.d/20-chrony-dhcp/etc/NetworkManager/dispatcher.d/20-chrony-onoffline/etc/chrony.conf/etc/chrony.keys/etc/dhcp/dhclient.d/chrony.sh/etc/logrotate.d/chrony/etc/sysconfig/chronyd/usr/bin/chronyc/usr/lib/.build-id/usr/lib/.build-id/38/usr/lib/.build-id/38/1d3a324ce66865ba879dfa43d49e0e0c1e2c41/usr/lib/.build-id/43/usr/lib/.build-id/43/444c816fcf0802c43011f282afaf9feded4c56/usr/lib/systemd/ntp-units.d/50-chronyd.list/usr/lib/systemd/system/chrony-dnssrv@.service/usr/lib/systemd/system/chrony-dnssrv@.timer/usr/lib/systemd/system/chrony-wait.service/usr/lib/systemd/system/chronyd.service/usr/libexec/chrony-helper/usr/sbin/chronyd/usr/share/doc/chrony/usr/share/doc/chrony/FAQ/usr/share/doc/chrony/NEWS/usr/share/doc/chrony/README/usr/share/doc/chrony/ntp2chrony.py/usr/share/licenses/chrony/usr/share/licenses/chrony/COPYING/usr/share/man/man1/chronyc.1.gz/usr/share/man/man5/chrony.conf.5.gz/usr/share/man/man8/chronyd.8.gz/var/lib/chrony/var/lib/chrony/drift/var/lib/chrony/rtc/var/log/chrony

[root@kvm ~]# cat /etc/chrony.confpool 2.centos.pool.ntp.org iburst​# Record the rate at which the system clock gains/losses time.driftfile /var/lib/chrony/drift​# Allow the system clock to be stepped in the first three updates# if its offset is larger than 1 second.makestep 1.0 3​# Enable kernel synchronization of the real-time clock (RTC).rtcsync​# Enable hardware timestamping on all interfaces that support it.#hwtimestamp *​# Increase the minimum number of selectable sources required to adjust# the system clock.#minsources 2​# Allow NTP client access from local network.allow 0/0​# Serve time even if not synchronized to a time source.local stratum 10​# Specify file containing keys for NTP authentication.keyfile /etc/chrony.keys​# Get TAI-UTC offset and leap seconds from the system tz database.leapsectz right/UTC​# Specify directory for log files.logdir /var/log/chrony​# Select which information is logged.#log measurements statistics tracking

[root@kvm ~]# systemctl start chronyd[root@kvm ~]#[root@kvm ~]#[root@kvm ~]# systemctl status chronyd● chronyd.service - NTP client/server   Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled; vendor preset: enabled)   Active: active (running) since Fri 2023-09-08 19:02:50 CST; 2min 43s left     Docs: man:chronyd(8)           man:chrony.conf(5)  Process: 11542 ExecStopPost=/usr/libexec/chrony-helper remove-daemon-state (code=exited, status=0/SUCCESS)  Process: 11552 ExecStartPost=/usr/libexec/chrony-helper update-daemon (code=exited, status=0/SUCCESS)  Process: 11547 ExecStart=/usr/sbin/chronyd $OPTIONS (code=exited, status=0/SUCCESS) Main PID: 11550 (chronyd)    Tasks: 1 (limit: 52427)   Memory: 924.0K   CGroup: /system.slice/chronyd.service           └─11550 /usr/sbin/chronyd​Sep 08 19:02:50 kvm chronyd[11550]: chronyd version 4.2 starting (+CMDMON +NTP +REFCLOCK +RTC +PRIVDROP +SCFILTER +SIGND +ASYNCDNS +NTS +SECHASH +IPV6 +DEBUG)Sep 08 19:02:50 kvm chronyd[11550]: Frequency 1.633 +/- 0.046 ppm read from /var/lib/chrony/driftSep 08 19:02:50 kvm chronyd[11550]: Using right/UTC timezone to obtain leap second dataSep 08 19:02:50 kvm systemd[1]: Started NTP client/server.Sep 08 19:02:55 kvm chronyd[11550]: Selected source 36.110.233.85 (2.centos.pool.ntp.org)Sep 08 19:02:55 kvm chronyd[11550]: System clock wrong by -791.549636 secondsSep 08 18:49:44 kvm chronyd[11550]: System clock was stepped by -791.549636 secondsSep 08 18:49:44 kvm chronyd[11550]: System clock TAI offset set to 37 secondsSep 08 18:50:49 kvm chronyd[11550]: Selected source 119.28.206.193 (2.centos.pool.ntp.org)Sep 08 18:54:07 kvm chronyd[11550]: Source 81.16.177.123 replaced with 78.46.102.180 (2.centos.pool.ntp.org)[root@kvm ~]#[root@kvm ~]# netstat -tunlp |grep chronyudp        0      0 0.0.0.0:123             0.0.0.0:*                           11550/chronydudp        0      0 127.0.0.1:323           0.0.0.0:*                           11550/chronydudp6       0      0 ::1:323                 :::*                                11550/chronyd[root@kvm ~]#[root@kvm ~]# chronyc sources -v​  .-- Source mode  '^' = server, '=' = peer, '#' = local clock. / .- Source state '*' = current best, '+' = combined, '-' = not combined,| /             'x' = may be in error, '~' = too variable, '?' = unusable.||                                                 .- xxxx [ yyyy ] +/- zzzz||      Reachability register (octal) -.           |  xxxx = adjusted offset,||      Log2(Polling interval) --.      |          |  yyyy = measured offset,||                                \     |          |  zzzz = estimated error.||                                 |    |           \MS Name/IP address         Stratum Poll Reach LastRx Last sample===============================================================================^- 79.133.44.136                 1   6   377    56    -10ms[  -10ms] +/-  138ms^- electrode.felixc.at           2   6    33    55    +17ms[  +17ms] +/-  119ms^* 119.28.206.193                2   6   377    60  +1706us[+2327us] +/-   40ms^+ 36.110.233.85                 2   6   377    58  -1324us[-1324us] +/-   68ms

[root@node1 ~]# cat /etc/chrony.confserver 172.24.21.221 iburst​# Record the rate at which the system clock gains/losses time.driftfile /var/lib/chrony/drift​# Allow the system clock to be stepped in the first three updates# if its offset is larger than 1 second.makestep 3600 3​# Enable kernel synchronization of the real-time clock (RTC).rtcsync​# Enable hardware timestamping on all interfaces that support it.#hwtimestamp *​# Increase the minimum number of selectable sources required to adjust# the system clock.#minsources 2​# Allow NTP client access from local network.#allow 192.168.0.0/16​# Serve time even if not synchronized to a time source.#local stratum 10​# Specify file containing keys for NTP authentication.#keyfile /etc/chrony.keys​# Specify directory for log files.logdir /var/log/chrony​# Select which information is logged.#log measurements statistics tracking

[root@node1 ~]# chronyc sources -v210 Number of sources = 1​  .-- Source mode  '^' = server, '=' = peer, '#' = local clock. / .- Source state '*' = current synced, '+' = combined , '-' = not combined,| /   '?' = unreachable, 'x' = time may be in error, '~' = time too variable.||                                                 .- xxxx [ yyyy ] +/- zzzz||      Reachability register (octal) -.           |  xxxx = adjusted offset,||      Log2(Polling interval) --.      |          |  yyyy = measured offset,||                                \     |          |  zzzz = estimated error.||                                 |    |           \MS Name/IP address         Stratum Poll Reach LastRx Last sample===============================================================================^* 172.24.21.221                 3   6   377    37  -7753ns[ +140us] +/-   29ms