Chrony
chrony CentOS 7 同步时间
情景
某LAN 内有 3 台机器，需要保持LAN内机器时间一致。
A-机器IP: 192.168.137.100
B-机器IP: 192.168.137.101
C-机器IP: 192.168.137.102
分析
以 A-机器作为时间服务器，B-机器、C-机器 的时间与 A-机器 的时间同步即可。
操作
-
修改 A 机器
/etc/chrony.conf文件添加：
server 192.168.137.100 iburst # NTP 服务器 allow 192.168/16 # 服务端允许连接的客户端网段 local stratum 10如:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51[root@192 ~]# cat /etc/chrony.conf
# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
#server 0.centos.pool.ntp.org iburst
#server 1.centos.pool.ntp.org iburst
#server 2.centos.pool.ntp.org iburst
#server 3.centos.pool.ntp.org iburst
server 192.168.137.100 iburst
# Ignore stratum in source selection.
stratumweight 0
# Record the rate at which the system clock gains/losses time.
driftfile /var/lib/chrony/drift
# Enable kernel RTC synchronization.
rtcsync
# In first three updates step the system clock instead of slew
# if the adjustment is larger than 10 seconds.
makestep 10 3
# Allow NTP client access from local network.
allow 192.168/16
# Listen for commands only on localhost.
bindcmdaddress 127.0.0.1
bindcmdaddress ::1
# Serve time even if not synchronized to any NTP server.
local stratum 10
keyfile /etc/chrony.keys
# Specify the key used as password for chronyc.
commandkey 1
# Generate command key if missing.
generatecommandkey
# Disable logging of client accesses.
noclientlog
# Send a message to syslog if a clock adjustment is larger than 0.5 seconds.
logchange 0.5
logdir /var/log/chrony
#log measurements statistics tracking
[root@192 ~]#
-
修改 B、C 机器
/etc/chrony.conf文件添加：
server 192.168.137.100 iburst # NTP 服务器 local stratum 10如:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51[root@192 ~]# cat /etc/chrony.conf
# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
#server 0.centos.pool.ntp.org iburst
#server 1.centos.pool.ntp.org iburst
#server 2.centos.pool.ntp.org iburst
#server 3.centos.pool.ntp.org iburst
server 192.168.137.100 iburst
# Ignore stratum in source selection.
stratumweight 0
# Record the rate at which the system clock gains/losses time.
driftfile /var/lib/chrony/drift
# Enable kernel RTC synchronization.
rtcsync
# In first three updates step the system clock instead of slew
# if the adjustment is larger than 10 seconds.
makestep 10 3
# Allow NTP client access from local network.
#allow 192.168/16
# Listen for commands only on localhost.
bindcmdaddress 127.0.0.1
bindcmdaddress ::1
# Serve time even if not synchronized to any NTP server.
local stratum 10
keyfile /etc/chrony.keys
# Specify the key used as password for chronyc.
commandkey 1
# Generate command key if missing.
generatecommandkey
# Disable logging of client accesses.
noclientlog
# Send a message to syslog if a clock adjustment is larger than 0.5 seconds.
logchange 0.5
logdir /var/log/chrony
#log measurements statistics tracking
[root@192 ~]#
-
重启 chrond 服务
重启A、B、C机器的chronyd 服务
1
2[root@192 ~]# systemctl restart chronyd.service
[root@192 ~]# -
同步时间
在 B、C 机器执行
chronyc -a makestep同步时间即可。
注意事项
1.chronyd 与 ntpd 服务是两个相同功能的东西，不能同时运行。
也就是说，chronyd 的 status 是 running 时，ntpd 的 status 应是dead。
2.同步失败，注意防火墙。
相关命令
1 | chronyc sources # chrony 源 |
