- grep
- curl
# error_log /usr/local/nginx/logs/error.log;
server {
listen 80;
server_name 192.168.60.123;
location / {
root /server/soft_pkgs;
autoindex on;
autoindex_localtime on; #之类的参数写这里
autoindex_exact_size off;
}
location /ngx_status {
auth_basic "secret";
auth_basic_user_file /usr/local/nginx/conf/.pass;
stub_status on;
# access_log off;
allow 127.0.0.1;
allow 192.168.10.0/24;
allow 192.168.60.0/24;
deny all;
}
location /ngx_statuss {
auth_basic "secret";
auth_basic_user_file /usr/local/nginx/conf/.pass;
check_status;
# access_log off;
#allow IP;
#deny all;
}
}
nload 总流量
nethogs 针对程序
iptraf 针对ip
yum install nload iptraf nethogs -y
cpu/内存/磁盘: htop/iotop搞定
for win:
## 查连接
netstat -ano | find "ESTABLISHED"
## 通过端口查进程
tasklist | find "2968"
## wireshark抓包过滤
cat >> /etc/bashrc<<EOF
unalias ll
unalias l.
alias ll='ls -hltrAF --time-style=full-iso'
alias lu='ls -AF| xargs du -sh|sort -rn'
EOF
source /etc/bashrc
tail -n 4 /etc/bashrc
大于30天没访问,且大小超过100M的
find /tmp -atime +30 -a –size +100M -exec 'rm -rf *' \;
-
选择64bit的python3
-
选择自定义安装
-
选择安装位置
import yagmail
yag = yagmail.SMTP(user='lannymxl@sina.com', password='ccc', host='smtp.sina.com', port='25',smtp_ssl=False)
yag.send('iher@163.com', subject="I now can send an attachment", contents='<h1 style="color:red">hello world</h1>')
- 样式
<h1>hello world</h1> 这样写邮件可以显显示格式
<h1 style="color:red">hello world</h1> 这样可以加载css. 但是如果以头文件引用css文件,或者style标签,邮件乱码
附件有监控个一个例子
- history 补全
- alias
- 输入输出重定向
- 管道
- 变量
- 环境变量
- 位置参数变量
- 预定义变量
- 数值运算
- 字符串处理(cut/printf/awk/sed)
- 正则
- 条件判断 if,case,for,while
-
磁盘结构(raid)[磁盘物理结构及大小计算]
-
MBR分区- fdisk分区 挂载 自动挂载 -> inode block -> 软硬链接
-
格式化(文件系统)(inode/block)
-
安装os
-
优化os
-
安装rpm(数据/日志+服务管理)
- 服务的分类
- 安装
- (数据/日志+服务管理)
- 进程管理
- 任务管理
- 定时任务
- rpm包管理
- 进程管理
- 工作管理
- 系统资源查看
- 定时任务
- rsyslog
- 日志滚动
- 启动管理
- 运行级别
- 启动过程
- grub配置/加密
- 系统修复 备份恢复
- 文件
- 目录
- 链接
- 权限管理
- 文件搜索
- 权限管理:
- ACL
- 特殊权限:SUID/SGID
- chattr
- sudo
三部曲:
- 1,vm会搭建服务
- 2,docker会跑服务
- 3,k8s集群会调度该服务
存储
- vm1 vm2 共享存储,vm1的容器挂了直接调度到vm2(docker存储驱动实现)
网络
- 物理机安装flannel,使两台docker上容器能通(物理机/容器搭建etcd集群)
- 物理机搭建openvswitch,实现两台docker
监控
- cadvisor会跑
- 物理机安装grafana,物理机安装promethus(实现nodeexplore和mysqlexplore)
- 容器跑promethus +cadvisor+grafana
- 容器跑cadvisor+influendb+grafana
- 容器跑elk,物理机跑filebeat搜集容器日志
umask: 022 (666-022)644
(777-022)755
umask 045(所有奇数位都要+1)-->046
777 - 046 = 731
666 - 046 = 620
chmod a+x file.txt #而不是chmod o+x file.txt
- 下载安装 MySQL Community Server 5.7.16 http://dev.mysql.com/downloads/mysql/
cd D:\Program Files\mysql-5.7.19-winx64\bin
mysqld --initialize-insecure
- 添加path
D:\Program Files\mysql-5.7.19-winx64\bin
- 启动MySQL服务
"D:\Program Files\mysql-5.7.19-winx64\bin\mysqld" --install
net start mysql
mysql -u root -p
"D:\Program Files\mysql-5.7.19-winx64\bin\mysqld" --remove
net stop mysql
create database bbs;
grant all on bbs.* to dev@localhost identified by '123456';
grant all on bbs.* to dev@'%' identified by '123456';
- 字符集
SET NAMES 'utf8';
SET character_set_client = utf8;
SET character_set_connection = utf8;
SET character_set_database = utf8;
SET character_set_results = utf8;
SET character_set_server = utf8;
SET collation_connection = utf8_general_ci;
SET collation_database = utf8_general_ci;
SET collation_server = utf8_general_ci;
缺陷是: 登出后设置的就失效了.
- 另一种配置文件持久化:
D:\Program Files\mysql-5.7.19-winx64\my.ini
[mysqld]
default-storage-engine = innodb
innodb_file_per_table = 1
character-set-server = utf8
collation-server = utf8_general_ci
init-connect = 'SET NAMES utf8'
[mysql]
default-character-set = utf8
[mysql.server]
default-character-set = utf8
[mysqld_safe]
default-character-set = utf8
[client]
default-character-set = utf8
参考: http://blog.csdn.net/u013474104/article/details/52486880
show variables like '%storage_engine%';
show VARIABLES like '%max_allowed_packet%';
show variables like '%storage_engine%';
show variables like 'collation_%';
show variables like 'character_set_%';
-
mysql生产配置参考 https://www.teakki.com/p/57e227aea16367940da625f8
-
配置文件查找先后顺序
C:\ProgramData\MySQL\MySQL Server 5.7\my.ini
C:\windows\my.ini
C:\my.ini
E:\dev\mysql57\my.ini
通过配置文件设置字符集
default-storage-engine = innodb
innodb_file_per_table = 1
character-set-server = utf8
collation-server = utf8_general_ci
init-connect = 'SET NAMES utf8'
- 查看建表语句
show create database test;
- 查看权限
show grants
- 源优化
cp /etc/apt/sources.list /etc/apt/sources.list_backup
cat >> /etc/apt/sources.list <<EOF
deb-src http://archive.ubuntu.com/ubuntu xenial main restricted #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb http://mirrors.aliyun.com/ubuntu/ xenial multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse #Added by software-properties
deb http://archive.canonical.com/ubuntu xenial partner
deb-src http://archive.canonical.com/ubuntu xenial partner
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-security universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-security multiverse
EOF
apt-get update
- pip优化
apt-get install python-pip -y
cd
mkdir ~/.pip
cat >> .pip/pip.conf <<EOF
[global]
index-url = http://mirrors.aliyun.com/pypi/simple/
[install]
trusted-host=mirrors.aliyun.com
EOF
- 时间优化
rm -rf /etc/localtime && cp /usr/share/zoneinfo/Asia/Shanghai /etc/localtime && ntpdate time-nw.nist.gov
- 优化
git clone https://github.com/chxuan/vimplus.git
cd ./vimplus
sudo ./install.sh
- 255 251 232
- FFFBE8
git rm -r --cached
-
最终效果
-
背景色前景色设置
-
修改gitbash提示符
C:\Program Files\Git\etc\profile.d\git-prompt.sh
C:\Program Files\Git\etc\vimrc
• ~/.bash_profile：用户每次登录时执行
• ~/.bashrc：每次进入新的Bash环境时执行
• ~/.bash_logout：用户每次退出登录时执行
yum install sendmail -y
cat >>/etc/mail.rc<<EOF
set from=xxx@tt.com
set smtp=smtp.exmail.qq.com
set smtp-auth-user=xxx@tt.com
set smtp-auth-password=123456
set smtp-auth=login
EOF
source /etc/mail.rc
- 发消息
echo "test"| mail -s "邮件标题" iher@foxmail.com
- 发文件
mail -s "邮件标题" iher@foxmail.com < /etc/passwd
- 发附件
mail -s "邮件标题" -a /var/log/messages iher@Foxmail.com < /etc/passwd
- 邮件相关目录
C6 postfix /var/spool/postfix/maildrop
C5 sedmail /var/spool/clientmqueue
注: centos6.5已经不自动安装sendmail了所以没必要走这一步优化
- 写脚本自动清理邮箱
mkdir -p /server/scripts
cat /root/shell/spool_clean.sh
#!/bin/sh
find/var/spool/clientmqueue/-type f -mtime +30|xargs rm-f
echo '*/30 * * * * /bin/sh /server/scripts/spool_clean.sh >/dev/null 2>&1'>>/var/spool/cron/root
- 查本地支持的所有字符集
# locale -a
- 查当前使用的字符集
locale #调取了/etc/sysconfig/i18n
- 系统默认字符集:
export LANG='zh_CN.UTF-8'
- 监控网卡流量历史流量
yum install sysstat
sar -n DEV 1 5 #1s监控1次,共监控5次.
sar -n DEV (-n network)
watch more /proc/net/dev
- mtime 10天内 10天外
find . -mtime +10 -exec rm -rf {} \;
find . -mtime +10|xargs rm -f
$ nc -vuz 192.168.6.6 53
Connection to 192.168.6.6 53 port [udp/domain] succeeded!
实际使用时可以只用-u参数，-u代表udp协议 ，-v代表详细模式，-z代表只监测端口不发送数据。
- client发交互式到服务器的console
nc -l -u 8021 --server #可以配置tcpdump -i eth0 port 8021 -nnv抓包
nc -u 192.168.6.52 8021 --client #交互式发送消息
- client发文件到服务端console
server: nc -l -u 8021
client: nc -u 192.168.6.52 8021 < /etc/hosts
- tar+nc传文件
server： tar -cf - /home/database | nc -l 5677 #将/home/database文件
client： nc 192.168.6.52 5677 | tar -xf - #传到client的当前目录
openssl rand -hex 8
$mkpasswd -l 16 -s 2
3Hte^bd-pkylSbf7
echo "ansible"|passwd --stdin ansible #centos7改用户密码
- fstab挂载硬盘
cat /etc/fstab
需挂载的设备 挂载点 fs类型 参数 备份 检查
/dev/mapper/centos-data /data xfs defaults 0 0
- nfs挂载(centos7放fstab)
192.168.8.68:/data/backup/no75/confluence/data /data/confluence/ nfs defaults 0 0
- nfs挂载(centos6放/etc/rc.local里即可)
/usr/bin/mount -t nfs 192.168.8.68:/data/owncloud /data/owncloud-192.168.8.68
- nfs服务端设置:
/data/backup/no75/confluence/data 192.168.8.0/24(rw,sync,no_root_squash)
- (磁盘扩容)关于tmpfs空间满，会影响其中的服务使用吗
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 32G 1.3G 29G 5% /
tmpfs 16G 16G 0 100% /dev/shm
mount -o remount,size=18G /dev/shm
- 只读mount
Mount the file system and make it writeable
mount -uw /
Make the filesystem read only again.
mount -ur /
- 前一天日期
date +%Y-%m-%d~%H-%M-%S -d "-1 day"
date "+%Y-%m-%d %H-%M-%S" -d "-1 day"
- 压缩带日期
tar zcvf etc_$(date +%F -d "-1 day").tar.gz /etc/
- 时区校准
rm -rf /etc/localtime && cp /usr/share/zoneinfo/Asia/Shanghai /etc/localtime && ntpdate ntp1.aliyun.com
- 设置同步时间
/user/sbin/ntpdate ntp1.aliyun.com
echo '*/5 * * * * /usr/sbin/ntpdate ntp1.aliyun.com >/dev/null 2 >&1' >>/var/spool/cron/root
- 手动修改时间
date -s "2016/06/11 22:50"
ifconfig eth0|grep -oP "([0-9]{1,3}\.){3}[0-9]{1,3}"|sed -n '1p'
ifconfig|sed -n '2p'|sed -r 's#^.*addr:(.*) Bcast.*$#\1#g'
ifconfig|sed -n '2p'|awk -F':' '{print $2}'|awk '{print $1}'
echo "stty erase ^H" >>/root/.bash_profile
source /root/.bash_profile
How to install dig, host, and nslookup – bind-utils on CentOS:
yum install bind-utils -y [c6使用nslookup]
yum install net-tools -y [c7使用ifconfig]
setenforce 0
sed -i 's#SELINUX=enforcing#SELINUX=disabled#g' /etc/selinux/config
getenforce
/etc/init.d/iptables stop
ulimit -SHn 65535
echo '* - nofile 65536' >>/etc/security/limits.conf
echo "* soft nproc 65535" >>/etc/security/limits.conf
echo "* hard nproc 65535" >>/etc/security/limits.conf
echo "* soft nofile 65535" >>/etc/security/limits.conf
echo "* hard nofile 65535" >>/etc/security/limits.conf
> /etc/issuse
>/etc/redhat-release
$ useradd sunsky
$ echo "123456"|passwd --stdin sunsky&&history –c
$ visudo # 99gg
在root ALL=(ALL) ALL #此行下，添加如下内容
sunsky ALL=(ALL) ALL
lanny ALL=(ALL) ALL=/sbin/mount /mnt/cdrom, /sbin/umount /mnt/cdrom #仅允许他执行这些命令
\cp /etc/ssh/sshd_config /etc/ssh/sshd_config.ori
sed -i 's#\#UseDNS yes#UseDNS no#g' /etc/ssh/sshd_config
sed -i 's#GSSAPIAuthentication yes#GSSAPIAuthentication no#g' /etc/ssh/sshd_config
/etc/init.d/sshd restart
Port 22345
PermitRootLogin no
PermitEmptyPasswords no
UseDNS no
ListenAddress 192.168.138.24
GSSAPIAuthentication no
export TMOUT=10
echo "export TMOUT=10" >>/etc/profile
source /etc/profile
yum -y install vim-enhanced
cat >>/etc/vimrc<<a
set nu
set cursorline
set nobackup
set ruler
set autoindent
set vb t_vb=
set ts=4
set expandtab
set paste
set fileencodings=utf-8,ucs-bom,cp936
syntax on
set hls
a
. /etc/vimrc
- rsync server配置(rpm -qa|grep rsync):
cat /usr/local/rsync/rsync.conf
uid = root
gid = root
use chroot = no
max connections = 10
strict modes = yes
pid file = /var/run/rsyncd.pid
lock file = /var/run/rsync.lock
log file = /var/log/rsyncd.log
[web]
path = /code/pp100web/target/ROOT
comment = web file
ignore errors
read only = no
write only = no
hosts allow = 192.168.14.132
list = false
uid = root
gid = root
auth users = webuser
secrets file = /usr/local/rsync/rsync.passwd
- 重启rsync
kill -HUP `cat /var/run/rsyncd.pid`
/usr/bin/rsync --daemon --config=/usr/local/rsync/rsync.conf
ps -ef|grep rsync
- 配置允许同步的的客户端
vim /usr/local/rsync/rsync.conf
hosts allow = 192.168.14.132,192.168.14.133
注意:密码文件统一600,且普通用户为谁,属主即为谁.
export JAVA_HOME=/usr/local/jdk
export PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$PATH
export CLASSPATH=.$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib:$JAVA_HOME/lib/tools.jar
export TOMCAT_HOME=/usr/local/tomcat
export CATALINA_BASE="/data/tomcat"
export PATH=/usr/local/mysql/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/jdk1.7.0_45/bin:/root/bin:/usr/local/jdk1.7.0_45/bin:/root/bin
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-6.repo
wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-6.repo
yum clean all
yum makecache
yum install lrzsz ntpdate sysstat dos2unix wget telnet tree -y
crontab -l
*/5 * * * * /usr/sbin/ntpdate times.windows.com >/dev/null 2>&1
stty erase "^H" #追加到/etc/profile
export HISTTIMEFORMAT="%F %T `whoami` "
echo "export HISTTIMEFORMAT="%F %T `whoami` "" >> /etc/profile
export PROMPT_COMMAND='{ msg=$(history 1 | { read x y; echo $y; });logger "[euid=$(whoami)]":$(who am i):[`pwd`]"$msg";}'
cat /etc/salt/master |grep -v "#" | sed '/^$/d'
grep -nir
-i 不区分大小写
-n 显示行号
-r 查找目录, grep -r 'xx' .
/usr/bin/killall -HUP syslogd
/bin/kill -USR1 $(cat /var/run/nginx.pid 2>/dev/null) 2>/dev/null || :
echo "net.ipv4.icmp_echo_ignore_all=1">>/etc/sysctl.conf
tail -1 /etc/sysctl.conf
sysctl -p
echo 1 > /proc/sys/net/ipv4/ip_forward #这样好处可以tab
sysctl -w net.ipv4.ip_forward=1 #好像没写到/etc/sysctl.conf里
sed -i 'N;4addpdf' a.txt
sed -i 'N;4ieepdf' a.txt
sed -i 'N;4a44444444444444444444444444testt' 1.log在第四行后加一行
http://www.361way.com/sed-process-lines/2263.html
sed -i 's#^\#set bell-style none#set bell-style none#g' /etc/inputrc
echo "modprobe -r pcspkr" > /etc/modprobe.d/blacklist
\cp /etc/init/control-alt-delete.conf /etc/init/control-alt-delete.conf.bak
sed -i 's#exec /sbin/shutdown -r now "Control-Alt-Deletepressed"#\#exec /sbin/shutdown -r now "Control-Alt-Deletepressed"#g'
yum groupinstall base -y
yum groupinstall core -y
yum groupinstall development libs -y
yum groupinstall development tools -y
echo -e "\033[32m crontab has been added successfully \033[0m"
- 服务端&客户端
yum install nfs-utils rpcbind -y
- 服务端:
/etc/init.d/rpcbind start
ps -ef |grep rpc
/etc/init.d/rpcbind status
rpcinfo -p localhost
- 服务端配置共享目录
echo "/data 10.0.0.0/24(rw,sync,no_root_squash)" >> /etc/exports
chkconfig rpcbind on
chkconfig nfs on
- 客户端挂载
/etc/init.d/rpcbind start
chkconfig rpcbind on
showmount -e 10.1.1.10
mount -t nfs 10.1.1.10:data /mnt
写到/etc/rc.local里
- 1.安装依赖
yum install pcre pcre-devel openssl openssl-devel –y
- 2.添加nginx用户
useradd -s /sbin/nologin -M nginx
- 3.编译安装
./configure --user=nginx --group=nginx --prefix=/usr/local/nginx-1.6.2 --with-http_stub_status_module --with-http_ssl_module
make && make install
echo $?
ln -s /usr/local/nginx-1.6.2 /usr/local/nginx
- 4.检查nginx.conf语法
/usr/local/sbin/nginx # -t检查配置文件语法
/usr/local/nginx/sbin/nginx # 启动
- 5.添加nginx服务到PATH
echo PATH=/application/nginx/sbin/:$PATH >> /etc/profile
source /etc/profile
netstat -ntulp |grep nginx
lsof -i:80
curl 192.168.14.151
nginx -s stop
nginx -s reload
- 7.nginx反代配置nignx.conf
worker_processes auto;
events {
multi_accept on;
use epoll;
worker_connections 51200;
}
error_log stderr notice;
worker_rlimit_nofile 65535;
http {
include mime.types;
default_type application/octet-stream;
server_info off;
server_tag off;
server_tokens off;
server_name_in_redirect off;
client_max_body_size 20m;
client_header_buffer_size 16k;
large_client_header_buffers 4 16k;
sendfile on;
tcp_nopush on;
keepalive_timeout 65;
server_tokens on;
gzip on;
gzip_min_length 1k;
gzip_buffers 4 16k;
gzip_proxied any;
gzip_http_version 1.1;
gzip_comp_level 3;
gzip_types text/plain application/x-javascript text/css application/xml;
gzip_vary on;
upstream owncloud {
server 127.0.0.1:8000;
}
upstream confluence {
server 127.0.0.1:8090;
}
server {
listen 80;
server_name owncloud.maotai.org;
location / {
proxy_next_upstream error timeout invalid_header http_500 http_503 http_404 http_502 http_504;
proxy_pass http://owncloud;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
}
server {
listen 80;
server_name confluence.maotai.org;
location / {
proxy_next_upstream error timeout invalid_header http_500 http_503 http_404 http_502 http_504;
proxy_pass http://confluence;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
}
server {
listen 80;
server_name status-no189.maotai.org;
location /nginx_status {
stub_status on;
access_log off;
}
}
}
cat > /etc/logrotate.d/nginx
/usr/local/nginx/logs/*.log {
daily
missingok
rotate 7
dateext
compress
delaycompress
notifempty
sharedscripts
postrotate
if [ -f /usr/local/nginx/logs/nginx.pid ]; then
kill -USR1 `cat /usr/local/nginx/logs/nginx.pid`
fi
endscript
}
DEVICE=eth0
TYPE=Ethernet
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=static
IPADDR=192.168.6.28
NETMASK=255.255.255.0
GATEWAY=192.168.6.1
- Ubuntu的promote
export PS1="\[\e]0;\u@\h: \w\a\]${debian_chroot:+($debian_chroot)}\u@\h:\w\$"
- centos的promote
export PS1="[\u@\h \W]\$"
- yum安装lamp:
yum install -y httpd php php-cli php-common php-pdo php-gd
yum install -y httpd php php-cli php-common php-pdo php-gd mysql mysql-server php-mysql
yum install -y httpd php php-ldap php-gd
- php配置:
vim /etc/php.ini
729 post_max_size = 16M
946 date.timezone = PRC #(中华人民共和国)
cat adduser.sh
#!/bin/bash
# Add system user
for ldap in {1..5};do
if id user${ldap} &> /dev/null;then
echo "System account already exists"
else
adduser user${ldap}
echo user${ldap} | passwd --stdin user${ldap} &> /dev/null
echo "user${ldap} system add finish"
fi
done
# chmod +x adduser.sh
# ./adduser.sh
# id user1
uid=502(user1) gid=502(user1) groups=502(user1)
useradd test -u 6000 -g 6000 -s /sbin/nologin -M -d /dev/null
- 单独的
$*和$ @ 没区别 - "$*"和"$@"区别如下
[root@node1 ~]# cat test.sh
#!/bin/sh
for i in "$*";do
echo $i
done
[root@node1 ~]# sh test.sh 1 2 3 4
1 2 3 4
[root@node1 ~]# cat test.sh
#!/bin/sh
for i in "$@";do
echo $i
done
[root@node1 ~]# sh test.sh 1 2 3 4 5
1
2
3
4
5
[shell] linux exec与重定向
[shell] shell学习之变量
-
使用小括号为数组赋值
a=（1 2 3）注意: 默认空格隔开 -
为数组b赋值-方法1
$ b=(bbs www http ftp)
$ echo ${b[*]}
bbs www http ftp
- 打印出第一个和第三个数据项
$ echo ${b[0]};echo '*******';echo ${b[2]}
bbs
*******
http
注: 记住是小括号，不是大括号
- 为数组b赋值-方法2
name=(
alice
bob
cristin
danny
)
for i in "${!name[@]}";do
echo ${name[$i]}
done
- 取得数组元素的个数-方法1
length=${#array_name[@]}
- 取得数组元素的个数-方法2
length=${#array_name[*]}
- 取得数组单个元素的长度
lengthn=${#array_name[n]}
优化小结: 一清： 定时清理日志/var/spool/clientsqueue 一精： 精简开机启动服务 一增： 增大文件描述符 两优： linux内核参数的优化、yum源优化 四设：设置系统的字符集、设置ssh登录限制、设置开机的提示信息与内核信息、设置block的大小 七其他：文件系统优化、sync数据同步写入磁盘、不更新时间戳、锁定系统关键文件、时间同步、sudo集权管理、关闭防火墙和selinux
centos一键优化脚本:
- 1、centos6.5最小化安装后启动网卡
- 2、ifconfig查询IP进行SSH链接
- 3、更新系统源并且升级系统
- 4、系统时间更新和设定定时任
- 5、修改ip地址、网关、主机名、DNS
- 6、关闭selinux，清空iptables
- 7、创建普通用户并进行sudo授权管理
- 8、修改SSH端口号和屏蔽root账号远程登陆
- 9、锁定关键文件系统（禁止非授权用户获得权限）
- 10、精简开机自启动服务
- 11、调整系统文件描述符大小
- 12、设置系统字符集
- 13、清理登陆的时候显示的系统及内核版本
- 14、内核参数优化
- 15、定时清理/var/spool/clientmqueue
- 16、删除不必要的系统用户和群组
- 17、关闭重启ctl-alt-delete组合键
- 18、设置一些全局变量
\cp /etc/sysctl.conf /etc/sysctl.conf.$(date +%F)
cat >>/etc/sysctl.conf<<EOF
net.ipv4.tcp_fin_timeout = 2
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_keepalive_time = 600
net.ipv4.ip_local_port_range = 4000 65000
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.tcp_max_tw_buckets = 36000
net.ipv4.route.gc_timeout = 100
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_synack_retries = 1
net.core.somaxconn = 16384
net.core.netdev_max_backlog = 16384
net.ipv4.tcp_max_orphans = 16384
net.netfilter.nf_conntrack_max = 25000000
net.netfilter.nf_conntrack_tcp_timeout_established = 180
net.netfilter.nf_conntrack_tcp_timeout_time_wait = 120
net.netfilter.nf_conntrack_tcp_timeout_close_wait = 60
net.netfilter.nf_conntrack_tcp_timeout_fin_wait = 120
EOF
sysctl -p
注: 以下参数是对centos6.x的iptables防火墙的优化，防火墙不开会有提示，可以忽略不理。 如果是centos5.X需要吧netfilter.nf_conntrack替换成ipv4.netfilter.ip centos5.X为net.ipv4.ip_conntrack_max = 25000000
net.nf_conntrack_max = 25000000
net.netfilter.nf_conntrack_max = 25000000
net.netfilter.nf_conntrack_tcp_timeout_established = 180
net.netfilter.nf_conntrack_tcp_timeout_time_wait = 120
net.netfilter.nf_conntrack_tcp_timeout_close_wait = 60
net.netfilter.nf_conntrack_tcp_timeout_fin_wait = 120