更多內容請查看老男孩老師的書籍：《跟老男孩學習Linux運維：Web集羣實戰》或者運維課程。
首先查看當前開啓的服務有哪些：
老男孩老師的經驗告訴我們默認只需要開通下面5個必要服務即可：
sshd |sysstat|crond|network|rsyslog
首先查看當前自啓動的服務有哪些。由於工作環境基本上使用文本模式3級別，只需要查找3級別上開啓的服務即可。
命令如下：
[root@nfs ~]# LANG=en (先調整成英文字符集，以方便過濾字符串)
[root@nfs ~]# chkconfig --list |grep 3:on （查看3級別下所有自啓動的服務）
abrt-ccpp 0:off 1:off 2:off 3:on 4:off 5:on 6:off
abrtd 0:off 1:off 2:off 3:on 4:off 5:on 6:off
acpid 0:off 1:off 2:on 3:on 4:on 5:on 6:off
atd 0:off 1:off 2:off 3:on 4:on 5:on 6:off
auditd 0:off 1:off 2:on 3:on 4:on 5:on 6:off
blk-availability 0:off 1:on 2:on 3:on 4:on 5:on 6:off
cpuspeed 0:off 1:on 2:on 3:on 4:on 5:on 6:off
crond 0:off 1:off 2:on 3:on 4:on 5:on 6:off
haldaemon 0:off 1:off 2:off 3:on 4:on 5:on 6:off
ip6tables 0:off 1:off 2:on 3:on 4:on 5:on 6:off
irqbalance 0:off 1:off 2:off 3:on 4:on 5:on 6:off
lvm2-monitor 0:off 1:on 2:on 3:on 4:on 5:on 6:off
mdmonitor 0:off 1:off 2:on 3:on 4:on 5:on 6:off
messagebus 0:off 1:off 2:on 3:on 4:on 5:on 6:off
netfs 0:off 1:off 2:off 3:on 4:on 5:on 6:off
network 0:off 1:off 2:on 3:on 4:on 5:on 6:off
nfs 0:off 1:off 2:off 3:on 4:off 5:off 6:off
nfslock 0:off 1:off 2:off 3:on 4:on 5:on 6:off
postfix 0:off 1:off 2:on 3:on 4:on 5:on 6:off
rpcgssd 0:off 1:off 2:off 3:on 4:on 5:on 6:off
rsyslog 0:off 1:off 2:on 3:on 4:on 5:on 6:off
sshd 0:off 1:off 2:off 3:on 4:off 5:off 6:off
sysstat 0:off 1:on 2:on 3:on 4:on 5:on 6:off
udev-post 0:off 1:on 2:on 3:on 4:on 5:on 6:off
處理思路：
1.先關閉所有服務，再開啓需要保留的（默認只需要開通5個必要服務即可。）
操作過程：
[root@nfs ~]# chkconfig --list |grep 3:on |awk '{print "chkconfig",$1,"off"}' |bash
（關閉所有自啓動的服務）
[root@nfs ~]# chkconfig --list （查看是否所有的自服務是否都關閉了）
abrt-ccpp 0:off 1:off 2:off 3:off 4:off 5:off 6:off
abrtd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
acpid 0:off 1:off 2:off 3:off 4:off 5:off 6:off
atd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
auditd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
blk-availability 0:off 1:on 2:off 3:off 4:off 5:off 6:off
cpuspeed 0:off 1:on 2:off 3:off 4:off 5:off 6:off
crond 0:off 1:off 2:off 3:off 4:off 5:off 6:off
haldaemon 0:off 1:off 2:off 3:off 4:off 5:off 6:off
ip6tables 0:off 1:off 2:off 3:off 4:off 5:off 6:off
iptables 0:off 1:off 2:on 3:off 4:on 5:on 6:off
irqbalance 0:off 1:off 2:off 3:off 4:off 5:off 6:off
kdump 0:off 1:off 2:off 3:off 4:on 5:on 6:off
lvm2-monitor 0:off 1:on 2:off 3:off 4:off 5:off 6:off
mdmonitor 0:off 1:off 2:off 3:off 4:off 5:off 6:off
messagebus 0:off 1:off 2:off 3:off 4:off 5:off 6:off
netconsole 0:off 1:off 2:off 3:off 4:off 5:off 6:off
netfs 0:off 1:off 2:off 3:off 4:off 5:off 6:off
network 0:off 1:off 2:off 3:off 4:off 5:off 6:off
nfs 0:off 1:off 2:off 3:off 4:off 5:off 6:off
nfs-rdma 0:off 1:off 2:off 3:off 4:off 5:off 6:off
nfslock 0:off 1:off 2:off 3:off 4:off 5:off 6:off
ntpd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
ntpdate 0:off 1:off 2:off 3:off 4:off 5:off 6:off
postfix 0:off 1:off 2:off 3:off 4:off 5:off 6:off
psacct 0:off 1:off 2:off 3:off 4:off 5:off 6:off
quota_nld 0:off 1:off 2:off 3:off 4:off 5:off 6:off
rdisc 0:off 1:off 2:off 3:off 4:off 5:off 6:off
rdma 0:off 1:off 2:off 3:off 4:off 5:off 6:off
restorecond 0:off 1:off 2:off 3:off 4:off 5:off 6:off
rngd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
rpcbind 0:off 1:off 2:off 3:off 4:off 5:off 6:off
rpcgssd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
rpcsvcgssd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
rsyslog 0:off 1:off 2:off 3:off 4:off 5:off 6:off
saslauthd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
smartd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
sshd 0:off 1:off 2:off 3:off 4:off 5:off 6:off
svnserve 0:off 1:off 2:off 3:off 4:off 5:off 6:off
sysstat 0:off 1:on 2:off 3:off 4:off 5:off 6:off
udev-post 0:off 1:on 2:off 3:off 4:off 5:off 6:off
然後再執行一條命令去開啓需要自啓動的5個服務：
[root@nfs ~]# chkconfig --list |grep 3:off|egrep "sshd|sysstat|crond|network|rsyslog" |awk '{print "chkconfig",$1,"on"}'|bash （關閉所有自服務之後開啓需要自啓動的5個服務）
[root@nfs ~]# chkconfig --list |grep 3:on （查詢設置情況並看是否只保留了我們需要的5個自啓動服務）
crond 0:off 1:off 2:on 3:on 4:on 5:on 6:off
network 0:off 1:off 2:on 3:on 4:on 5:on 6:off
rsyslog 0:off 1:off 2:on 3:on 4:on 5:on 6:off
sshd 0:off 1:off 2:on 3:on 4:on 5:on 6:off
sysstat 0:off 1:on 2:on 3:on 4:on 5:on 6:off
2. 關掉不需要的，因爲我們需要的服務默認都是開啓的。
操作過程：
[root@nfs ~]# chkconfig --list |grep 3:on|egrep -v "sshd|sysstat|crond|network|rsyslog"|awk '{print "chkconfig",$1,"off"}'|bash
（一條命令排除我們需要保留的5個自啓動服務並關閉其他服務）
[root@nfs ~]# chkconfig --list |grep 3:on （查詢設置情況並看是否只保留了我們需要的5個自啓動服務）
crond 0:off 1:off 2:on 3:on 4:on 5:on 6:off
network 0:off 1:off 2:on 3:on 4:on 5:on 6:off
rsyslog 0:off 1:off 2:on 3:on 4:on 5:on 6:off
sshd 0:off 1:off 2:off 3:on 4:off 5:off 6:off
sysstat 0:off 1:on 2:on 3:on 4:on 5:on 6:off
相對來說第2個方法更簡單一點。大家可以根據需要靈活使用。
設置自啓動服務也可以通過setup和ntsysv來處理。