Original address: http://blog.csdn.net/babyfish13/article/details/52502522
CentOS 7 is different from the previous linux operation, and the command is different for the adjustment of boot-up. chkconfig --list view the self startup status of non system built-in services
- [root@master ~]# chkconfig --list
- Note: This output shows SysV services only and does not include native
- systemd services. SysV configuration data might be overridden by native
- systemd configuration.
- If you want to list systemd services use 'systemctl list-unit-files'.
- To see services enabled on particular target use
- 'systemctl list-dependencies [target]'.
- iprdump 0:off 1:off 2:on 3:on 4:on 5:on 6:off
- iprinit 0:off 1:off 2:on 3:on 4:on 5:on 6:off
- iprupdate 0:off 1:off 2:on 3:on 4:on 5:on 6:off
- netconsole 0:off 1:off 2:off 3:off 4:off 5:off 6:off
- network 0:off 1:off 2:on 3:on 4:on 5:on 6:off
- vmware-tools 0:off 1:off 2:on 3:on 4:on 5:on 6:off
According to the prompt, to view the built-in service self starting status of the system, you need to use the command systemctl list unit files, which lists the self starting status of all built-in services of the system.
So adjusting ntp self start needs to be adjusted here.
- [root@master ~]# systemctl enable ntpd.service / / booting
- Restart the system after adjustment, but it is found that ntp It didn't start
- [root@master ~]#pgrep ntpd / / unable to view related processes
- [root@master ~]# systemctl status ntpd
- ntpd.service - Network Time Service
- Loaded: loaded (/usr/lib/systemd/system/ntpd.service; enabled)
- Active: inactive (dead) //It shows that the power is started automatically, but the status is inactive
Through the query, it is found that a cronyd service is set to start from the start, which causes ntp to fail to start from the start
- [root@master ~]# systemctl status chronyd
- chronyd.service - NTP client/server
- Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled)
- Active: inactive (dead) since Tue 2014-11-11 08:28:14 CST; 1min 45s ago
- Main PID: 3033 (code=exited, status=0/SUCCESS)
- CGroup: /system.slice/chronyd.service
- Nov 11 08:06:31 master.zj.chinamobile.com systemd[1]: Starting NTP clien...
- Nov 11 08:06:31 master.zj.chinamobile.com chronyd[3033]: chronyd version...
- Nov 11 08:06:31 master.zj.chinamobile.com chronyd[3033]: Linux kernel ma...
- Nov 11 08:06:31 master.zj.chinamobile.com chronyd[3033]: hz=100 shift_hz...
- Nov 11 08:06:31 master.zj.chinamobile.com systemd[1]: Started NTP client...
- Nov 11 08:28:14 master.zj.chinamobile.com systemd[1]: Stopping NTP clien...
- Nov 11 08:28:14 master.zj.chinamobile.com systemd[1]: Stopped NTP client...
- Hint: Some lines were ellipsized, use -l to show in full.
By disabling the cronyd service from starting up and then restarting the system
- [root@master ~]# systemctl disable chronyd.service
- rm '/etc/systemd/system/multi-user.target.wants/chronyd.service'
- [root@master ~]# pgrep ntpd
- 2981
- [root@master ~]# ntpq -p
- remote refid st t when poll reach delay offset jitter
- ==============================================================================
- 10.70.213.132 10.70.91.148 3 u 21 64 1 1.252 0.029 0.000
- *10.70.213.133 10.70.91.148 3 u 21 64 1 1.139 -0.191 0.000
At this time, NTP service has been started and started. It is finished!
Frankly, in a word, because the chronyd is not disabled, ntpq can not start even if it is configured!
remarks:
Chrony is an open-source free software, which can keep the system clock and clock server (NTP) in synchronization and keep the time accurate. It is the new NTP time synchronization service in RHEL7.