linux 时间同步ntp和chrony服务搭建配置

admin

查看时间同步源的信息。
# chronyc sourcestats -v
210 Number of sources = 1
4 h! \9 F! ?  E" F9 t+ t                             .- Number of sample points in measurement set.
                            /    .- Number of residual runs with same sign.
: `6 P- T0 g# i) n3 ^# {) N) r                           |    /    .- Length of measurement set (time).
  u4 l  m8 b; o% J" h8 ^, p( {2 C                           |   |    /      .- Est. clock freq error (ppm).
1 c3 C7 w5 S$ j2 }: o                           |   |   |      /           .- Est. error in freq.
                           |   |   |     |           /         .- Est. offset.
                           |   |   |     |          |          |   On the -.
1 W. [3 K; y0 J  N4 r" Q3 q                           |   |   |     |          |          |   samples. \
8 J" B' c2 K( v: c& G0 J3 j) y                           |   |   |     |          |          |             |
7 a1 R: f! V$ F5 r8 dName/IP Address            NP  NR  Span  Frequency  Freq Skew  Offset  Std Dev
==============================================================================
promote.cache-dns.local     0   0     0     +0.000   2000.000     +0ns  4000ms

admin

[root@361way ~]# chronyc
chrony version 1.29.1
Copyright (C) 1997-2003, 2007, 2009-2013 Richard P. Curnow and others
chrony comes with ABSOLUTELY NO WARRANTY.  This is free software, and
% V, G8 b) ~7 L% x, U. _! s/ yyou are welcome to redistribute it under certain conditions.  See the
& C' T( R. m: _" z( CGNU General Public License version 2 for details.
chronyc> activity
% v: H5 q5 E/ S) d6 j, k& v200 OK
+ z$ y* o; O1 V3 Y, r3 E+ t3 sources online
1 l/ y( l: ?& P, ^0 sources offline
0 sources doing burst (return to online)
) L- s& t2 F, U* A+ c0 sources doing burst (return to offline)
  B! @: H/ U0 f' w5 f0 sources with unknown address
chronyc> help
1 [9 n4 u- }7 D' v& a! B, N6 ECommands:
accheck <address> : Check whether NTP access is allowed to <address>
" G( c8 U+ l7 e+ _. T' Ractivity : Check how many NTP sources are online/offline
add peer <address> ... : Add a new NTP peer
add server <address> ... : Add a new NTP server
allow [<subnet-addr>] : Allow NTP access to that subnet as a default
% F- B/ a3 k0 W/ s5 Wallow all [<subnet-addr>] : Allow NTP access to that subnet and all children
burst <n-good>/<n-max> [<mask>/<masked-address>] : Start a rapid set of measurements
clients : Report on clients that have accessed the server
cmdaccheck <address> : Check whether command access is allowed to <address>
8 A4 m, i& l- S" n) @0 P$ P4 ^) Icmdallow [<subnet-addr>] : Allow command access to that subnet as a default
cmdallow all [<subnet-addr>] : Allow command access to that subnet and all children
cmddeny [<subnet-addr>] : Deny command access to that subnet as a default
* F# i! x- _" e  y% O1 O8 w$ K……………………省略

admin

配置NTP server 服务器 #yum install -y ntp
●        编辑ntp 配置  vim /etc/ntp.conf
driftfile /var/lib/ntp/drift
restrict default nomodify notrap nopeer noquery
restrict 127.0.0.1
restrict ::1
server 127.127.1.0                              　　
* G$ N1 O3 F; u. _/ A* dfudge 127.127.1.0 stratum 0                  
includefile /etc/ntp/crypto/pw
! x. W; f" b4 ^5 H! O7 bkeys /etc/ntp/keys
disable monitor
●        编辑ntp 服务器的配置
# vim  /etc/sysconfig/iptables

! g" W6 k3 n) M2 l; c. g  -A INPUT -p udp --dport 123 -j ACCEPT

# systemctl restart iptables
# systemctl restart iptables.service
( a/ m- J/ B! A) S; p6 R) I●        将系统时间写入硬件
  # hwclock --systohc
: B. }6 S3 n, j  P7 w; _+ W●        重新启动NTP服务
$ E/ A6 c; C" l3 W! I) J, S* x8 F    # service ntpd restart
1 G$ X+ _1 m: m" x4 |9 `1 a
# P$ u( V* y. i. P0 t* i- @

admin

设定NTP主机来源（其中prefer表示优先主机），192.168.7.49是本地的NTP服务器，所以优先指定从该主机同步时间。

  {  S0 q8 e7 f8 f8 Hserver 192.168.7.49 prefer