We all know that can be used outside the network clock synchronization server, including when not connected to external networks within the network clock synchronization need, how to proceed?
A stable server within the network selected as the clock source, and then let the other machines are synchronized to the machine.
Note: In fact, almost the ntp service and service chrony nature, can be synchronized with each other between them. However, in order to avoid unnecessary trouble, generally only choose the same server to synchronize the clock in terms of service.
A, ntp service
Installation: yum install ntp
1, the server settings
Modify the configuration file cat /etc/ntp.conf
The following commented clock source external network (preceded by #)
If this network as the server, then the clock source, is provided as follows
ntp synchronize the local clock
server 127.127.1.0 # local clock
fudge 127.127.1.0 stratum 10
Demand modified as follows:
restrict 10.0.0.0 mask 255.255.255.0 # 10.0.0.0 allows access to the network server in the server for time synchronization ntp (according to its own network)
the restrict allows a single IP address 10.0.0.16 # ntp access to the server (by ip to)
restrict 192.168.111.0 mask 255.255.255.0 nomodify notrap # allow other machines within the network synchronization time, if you do not add the default constraint allows access to all IP native synchronization service
Other configurations do not make changes, save and exit the configuration file
Restart systemctl restart ntpd
View ntp status systemctl status nptd
Check whether the clock to synchronize: ntpq -p command to view with an asterisk * is synchronized
ntpstat command to check the time synchronization status, this normally takes 5-10 minutes to successfully connect and sync
。
2, the other client configuration:
vim /etc/ntp.conf
Commented at the beginning of the server
Adding server IP (here is the ip IP is the clock source of the upper end of the service) iburst
Systemctl restart ntpd to restart
See ntpq -p synchronization state, it has a value below the front and the asterisk * ip normal
二、chrony
Now a lot of latest machines are synchronized with the chrony
Installation: yum install chorny
Server:
Configuration: vim /etc/chrony.conf
Comment out the first network clock source, do as follows
server 127.0.0.1 iburst # local clock source
local stratum 10 # allows local synchronization
allow # Allow all connections
Boot: systemctl enable chronyd
Start Service: systemctl start chronyd
View status: systemctl status chronyd
View sync: chronyc sources -v with an asterisk * are successful synchronization
Or: timedatectl command, NPT synchronized to yes is the synchronization is complete
The client is then set as the clock source of this server
vim /etc/chrony.conf
server ip (on one side of the service ip) iburst
Coupled with his party
Allow all allow #
Save out.
chronyc sources view the synchronization status, configuration and just show ip ip there in front asterisk * ^ is the symbol of this success is failure