chrony配置介绍

rhel7 文档https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/System_Administrators_Guide/sect-Using_chrony.html

https://wiki.archlinux.org/index.php/Chrony

Note: systemd-timesyncd.service is in conflict with chrony, so you need to disable it first if you want to enable chrony properly.

SERVER1:

[root@r10o10405.sqa.zmf /home/ahao.mah]
#chronyc sources
210 Number of sources = 1
MS Name/IP address
Stratum Poll Reach LastRx Last sample
===============================================================================
^* 10.210.208.8
4
6
377
9
+398us[ +652us] +/-
64ms

#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 10.210.208.8 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.
# 如果误差大于10s，前3次update时间使用step而不是slew
makestep 10 3
# Allow NTP client access from local network.
#allow 192.168/16
allow
192.168.0.0/16
allow
172.16.0.0/14
allow
10.0.0.0/8
allow
11.0.0.0/8
allow
30.0.0.0/8
#allow 10.101.75.1/22
#allow 10.101.75.1
#allow
100.64.0.0 mask 255.192.0.0
# 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
#收集日志
log measurements statistics tracking

client

[root@r10o07276.sqa.zmf /home/ahao.mah]
#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 10.101.74.139
iburst
server 10.101.74.131
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. 简单说，如果误差大于10s，在头3次的时间更新中，会使用step，而不是slew
makestep 10 3
#makestep 1000 10
#简单说，如果误差大于1000s，在头10次的时间更新中，会使用step，而不是slew
#This would step the system clock if the adjustment is larger than 1000 seconds, but only in the first ten clock updates.
# 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

命令

client

[[root@r10o07276.sqa.zmf /home/ahao.mah]
#chronyc sources
210 Number of sources = 2
MS Name/IP address
Stratum Poll Reach LastRx Last sample
===============================================================================
^* r10o07413.sqa.zmf.tbsite.
5
6
377
64
-415us[ -274us] +/-
62ms
^+ r10o10405.sqa.zmf.tbsite.
5
6
377
1
-947us[ -947us] +/-
63ms

[root@r10o07276.sqa.zmf /home/ahao.mah]
#chronyc sources -v
210 Number of sources = 2
.-- 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
===============================================================================
^* r10o07413.sqa.zmf.tbsite.
5
6
377
1
-432us[ -702us] +/-
63ms
^+ r10o10405.sqa.zmf.tbsite.
5
6
377
2
-678us[ -947us] +/-
63ms

[root@r10o07276.sqa.zmf /home/ahao.mah]
#chronyc sourcestats
210 Number of sources = 2
Name/IP Address
NP
NR
Span
Frequency
Freq Skew
Offset
Std Dev
==============================================================================
r10o07413.sqa.zmf.tbsite.
6
3
325
-0.550
6.451
-232us
161us
r10o10405.sqa.zmf.tbsite.
7
3
387
+0.702
11.702
+235us
541us

[root@r10o07276.sqa.zmf /home/ahao.mah]
#chronyc sourcestats -v
210 Number of sources = 2
.- Number of sample points in measurement set.
/
.- Number of residual runs with same sign.
|
/
.- Length of measurement set (time).
|
|
/
.- Est. clock freq error (ppm).
|
|
|
/
.- Est. error in freq.
|
|
|
|
/
.- Est. offset.
|
|
|
|
|
|
On the -.
|
|
|
|
|
|
samples. 
|
|
|
|
|
|
|
Name/IP Address
NP
NR
Span
Frequency
Freq Skew
Offset
Std Dev
==============================================================================
r10o07413.sqa.zmf.tbsite.
6
3
325
-0.550
6.451
-233us
161us
r10o10405.sqa.zmf.tbsite.
7
3
387
+0.702
11.702
+237us
541us

[root@r10o10405.sqa.zmf /home/ahao.mah]
#chronyc tracking
Reference ID
: 10.210.208.8 (10.210.208.8)
Stratum
: 5
Ref time (UTC)
: Fri Feb 17 09:53:47 2017
System time
: 0.000000227 seconds slow of NTP time
Last offset
: +0.000335872 seconds
RMS offset
: 0.000938629 seconds
Frequency
: 23.669 ppm slow
Residual freq
: +0.560 ppm
Skew
: 10.502 ppm
Root delay
: 0.067548 seconds
Root dispersion : 0.030173 seconds
Update interval : 64.5 seconds
Leap status
: Normal