at

yum install at

Enable atd

[root@server12 ~]# service atd status
atd is stopped
[root@server12 ~]# chkconfig --list | grep atd
atd            	0:off	1:off	2:off	3:on	4:on	5:on	6:off
[root@server12 ~]# service atd start
Starting atd:                                              [  OK  ]
[root@server12 ~]# 

Setting Job

[root@server12 ~]# echo "/sbin/shutdown -h now"  |  at  21:15  16.02.2017
job 1 at 2017-02-16 21:15
[root@server12 ~]# atq
1	2017-02-16 21:15 a root
[root@server12 ~]# 

Deleting at job

[root@server12 ~]# atq
1	2017-02-16 21:15 a root
[root@server12 ~]# man atq
[root@server12 ~]# atrm 1
[root@server12 ~]# atq
[root@server12 ~]# 

See linux commands