Linux Basic optimization

1. Configure the Network

cat/etc/resolv.conf//View DNS

NETSTAT-RN//View Gateway

Vi/etc/sysconfig/network-scripts/ifcfg-eth0//Change network configuration

onboot= "Yes"

Bootproto=static

Add in this directory

Ipaddr= "IP"

netmask= "Subnets"

gateway= "Gateway"

dns1= "DNS"

ESC---input ": Wq"

/etc/init.d/network Restart//Restart Network

2. Configure Host

Vi/etc/sysconfig/network//change hostname (effective after reboot)

Hostname=zabbix.wtf.local//Change HOSTNAME

ESC---Enter ": Wq"//Save Exit

Hostname zabbix.wtf.local//Temporary VI Change host command

3. Firewall

/etc/init.d/iptables Status//view firewall configuration

/etc/init.d/iptables Stop//firewall off

Chkconfig iptables off//boot not boot firewall

4. Close Selnux

(1) Sed-i s#selinux=enforcing#selinux=disabled#g/etc/selinux/config//Turn off SELINUX

grep "Disable"/etc/selinux/config//See if replace succeeded

Getenforce 0//immediate effect

(2) Vi/etc/selinux/config//Turn off SELinux

Selinux=disabled

ESC---input ": Wq"

5. Yum Install tree telnet dos2unix sysstat lrzsz-y//install common software

6. Create User settings password

Useradd oldboy1//create User

passwd oldboy1//Add password

7. Switch users

Su-root//Switch User, must add-

8. Change the Yum source

Cp/etc/centos-base.repo Centos-base.repo.oir//backup original file

Cat/etc/yum.repos.d/centos-base.repo//view Yum source

wget http://mirrors.163.com/.help/CentOS6-Base-163.repo//download Yum source

CP Centos6-base-163.repo Centos-base.repo//replace original source

Yum grouplist//view installed package groups

9. Adjust the current mode

Vi/etc/inittab//view current mode, change to 3

0---shutdown mode

1---stand-alone mode

2---Multi-user mode

3---command-line mode

4---No usage mode

5---Desktop mode

6---Restart mode

init//Toggle Mode

10. Modify the boot entry

Chkconfig--list//View Startup items

11. Change the remote port

Vi/etc/ssh/sshd_config//Modify Port port number

12, under the ordinary user to use root permissions, sudo

Visudo//Edit normal user rights, edit in 99gg line, add format "Nopasswd:all"

sudo useradd 123

13, Chinese display (not recommended)

cat/etc/sysconfig/i18n//view Character Set

vi/etc/sysconfig/i18n//Edit Character Set

Lang= "ZH_CN. GB18030 "//Add this sentence

source/etc/sysconfig/i18n//Immediate effect

echo $LANG//See if it takes effect

14, Timing time synchronization

echo ' #time sync by Oldboy at 2010-2-1 ' >>/var/spool/cron/root

Echo ' */5****/usr/sbin/ntpdate time.nist.gov >/dev/null 2>&1 ' >>/var/spool/cron/root

Crontab-l//Check whether it takes effect

15. enlarge file descriptor (or 32768)

Ulimit-n//View file descriptor

ULIMIT-HSN 65535//pro-Active

Echo ' *-nofile 65535 ' >>/etc/security/limits.conf//Permanent

16. Adjust kernel parameters

vi/etc/sysctl.conf//Edit

SYSCTL-P//Effective documents

17, hidden version number

>/etc/issue

18. Lock Critical system files

Chattr +i/etc/passwd/etc/shadow/etc/group/etc/gshadow/etc/inittab//Lock critical system files

Chattr-i/etc/passwd/etc/shadow/etc/group/etc/gshadow/etc/inittab//Unlocking critical system files

LSATTR/ETC/PASSWD//See if the file is locked. Yes, I was locked.

This article is from the "11104762" blog, please be sure to keep this source http://11114762.blog.51cto.com/11104762/1812565

Linux Basic optimization