shopt –s expand_aliases   #可以这样进行enable

# man ascii

# ausyscall  --dump

# cat file |　awk '{ i=1;while(i<=NF) {print NF,$i;i++}}' file

# cat file |　awk '{ for(i=1;i<NF;i++) {print NF,$i}}' file

# cat file |  awk '{ if (NR<3)  print $1;  else print $2 }'

# cat file | sed -n '1,10p' |  awk '{ print $6 }' | awk 'BEGIN {sum=0}; {sum=sum+$1}; END {print sum}'

# total=`echo "scale=2;($throughput+$total)" | bc`

# chrt -p $pid  //显示进程的优先级属性
# chrt -m      //显示系统支持的最大/最小优先级值
# chrt -f -p 30 $pid
# chrt -f 30 $cmd

cpio -o -H newc ./* | gzip -n 9 > abc.cgz

# cpupower frequency-info //查看P-State相关信息
# cpupower idle-info  //查看C-State相关信息
# cpupower idle-set   //设置C-State相关状态

# dhparm  -a  /dev/sda

# dmidecode | grep "Product Name"

# ethtool eth0
# ethtool –s ethN speed 1000 duplex full port tp autoneg on

#!/bin/bash

fdisk /dev/sda <<END

m

p

END

# find / -mtime 50    #查找过去的第50天被修改过的文件
# find / -mtime -50   #查找过去50天内被修改过的文件
# find / -mtime +50   #查找50天前修改过的文件
# find / -mtime +50 -mtime +110 #查找过去110天前到过去50天前修改过的文件

# hash -l  //list所缓存的路径
# hash -r  //清空缓存

# hostnamectl
   Static hostname: localhost.localdomain
         Icon name: computer-laptop
           Chassis: laptop
        Machine ID: 447762032abf487799cd5dc26f9baa7b
           Boot ID: 81b94e038fcd4f3482ae9eb907b8f9ff
  Operating System: Fedora 26 (Workstation Edition)
       CPE OS Name: cpe:/o:fedoraproject:fedora:26
            Kernel: Linux 4.13.15-200.fc26.x86_64
      Architecture: x86-64
#

# ipmitool sensor

# grep  . ./test.txt /dev/null >2/dev/null （追加多个检索文件时会打印出文件名）

# growisofs -dvd-compat -Z /dev/dvdrw1=/mnt/fedora.iso

# gzip abc.cgz -dc | cpio -idumv

# ipcs –ma

# losetup  –f  xxx.img                （把img文件虚拟成硬盘）
# losetup  –a                         （查看）
# kpartx   –a  /dev/loopX             （映射分区，通过loseup –a查看获得）
# mount  /dev/mapper/loopXpX  /mnt

# umount  /mnt
# kpartx  –d  /dev/loopX
# loseup  –d  /dev/loopX

# pvscan                    (查看逻辑卷组)
# vgchange –ay $vol_group   (激活逻辑卷组)
# mount /dev/$vol_group/xxx /mnt

# ln -s /dev/loopN /dev/cdrom
# losetup /dev/loopN  ***.iso
# mount /dev/cdrom  /mnt/cdrom

# umount /mnt/cdrom
# loseup –d /dev/loop7

# lsblk

# lsblk -d -o name,rota /dev/sda
# cat /sys/block/sda/queue/rotational

# localectl
   System Locale: LANG=en_US.UTF-8
       VC Keymap: us
      X11 Layout: us
#

# loginctl
   SESSION        UID USER             SEAT             TTY
         2       1000 renyl            seat0            /dev/tty2
        c1         42 gdm              seat0            /dev/tty1

2 sessions listed.
#

# cat /proc/cpuinfo
# lscpu
# nproc
# getconf _NPROCESSORS_CONF

# lshw –c display
# lspci –vnn

# lspci -vvv

# mcpet-kvm -t  <秒数>

# mii-tool -w eth0 eth1

# mktemp  -dq  /tmp/file. XXXXXXXXXX (必须以X这种格式结尾)

# modinfo xfs

# mount -t nfs 192.168.2.14:/data/sdb2/RHEL_GA/RHEL7.2GA_x86_64/ /mnt/
# mount -o username=share,password=share  //10.167.226.124/share  /mnt

mount UUID=bf0c50bb-8b71-45f8-91e2-f197e2f8b7c9 /home/renyl/，如果能挂载成功，说明UUID没有错误。

# multipath –ll
# dmsetup ls

# multipath -F /dev/mapper/xxx
# dmsetup remove

# touch fileA
# mkdir dirA
# ln -sf dirA  linkA
# mv fileA linkA  => fileA will be put into dirA
# mv -T fileA linkA => file A will be rename linkA

# touch fileA
# mkdir dirA
# mv fileA dirA
# mkdir dirB

# mv dirA dirB    => dirA will be put into dirB
# mv -T dirA dirB => rename dirA to dirB, dirB must be a empty directory

# nc -l -k port  # -l参数表示listen，-k表示连续监听，port表示端口号
# nc -l port |   # 显示出来执行送给bash执行

# nc  ipaddr  port
# echo  "command" | nc ipaddress portnum

# ntpdate cn.pool.ntp.org
# hwclock -w

# numactl –hardware   （查看numa node）

openssl s_client -showcerts -connect www.baidu.com:443

# opcontrol –-vmlinux=/boot/vmlinuz-`uname –r` //设置是否监视内核

# opcontrol  --vmlinux=/usr/lib/debug/lib/modules/`uname -r`/vmlinux
# opcontrol  --no-vmlinux  //不监视内核

# opcontrol  -p/ --separate=none 
# opcontrol  -l/--list-events //查看可监视事件并设置

# opcontrol --event=DTLB_MISSES:6000:0x01:1:1
# opcontrol  -s/--start  //启动

# opcontrol  --init
# ./path/to/mybinary //运行待分析的程序

# opcontrol  -s/--start
# opcontrol –d/--dump //取数据

# ./my-start-run.sh.bak log-host-nopci-full-memory-oprofile-1
# opcontrol –t/--stop //停止

# opcontrol  -d/--dump
# opreport –l ./path/to/mybinary //分析结果

#opcontrol  -t/--stop

# /sbin/partprobe  #通知操作系统分区表发生的变化

pfmon –e L2D_MISSES ./test
  1652 L2D_MISSES

# powertop

# qemu-img create -f raw  myfile.img 8G cache=none

# rpm -ivh /home/qemu-kvm-0.12.1.2-2.209.el6.x86_64.rpm  --nodeps

# rpm -qp --scripts xxx.rpm

# rpm2cpio xxx.rpm | cpio –div

# for i  in `seq num1 num2`; do echo $i; done

# scp  192.168.11.4：/home/renyl/*    ./    (把远程的文件传到本地，可以使用*号)
# scp  localfile   192.168.11.4:/home/renyl (把本地的文件传到远程)

# ssh  root@192.168.122.92 (之间要有空格) “cd /home/renyl/; ./start_run.sh”

# ssh -L  [bind_address:]port:host:hostport <hostname>
# ssh -R  [bind_address:]port:host:hostport <hostname>

ssh -L 192.168.10.10:80:192.168.10.20:80 192.168.10.20
ssh -L 192.168.10.10:80:localhost:80 192.168.10.20

ssh -R 192.168.10.20:88:192.168.10.10:80 192.168.10.20
ssh -R 192.168.10.20:88:localhost:80 192.168.10.20

# ssh -g -L port:host:hostport <hostname>
# ssh -L 0.0.0.0:port:host:hostport <hostname>

Host allen-forward

	User renyl
	HostName lucky
	LocalForward localhost:6666 192.168.0.2:22

Host allen
	User renyl
	HostName localhost
	Port 6666

stty cols 231 rows 81

sync

sysctl -a #查看系统所有配置参数
sysctl -n kernel.hostname #打印参数值
sudo sysctl -w kernel.hostname="kulong0105" #改变参数值
sudo sysctl -p  #添加设置到/etc/sysctl.conf,使其重启后仍然有效

# smartctl -i /dev/sda

# timedatectl

unbind C-b
set -g prefix C-s
setw -g mode-keys vi

# split window like vim
# vim's defination of a horizontal/vertical split is revised from tumx's

bind b split-window -h
bind v split-window –v

# move arount panes wiht hjkl, as one would in vim after C-w
bind h select-pane -L
bind j select-pane -D
bind k select-pane -U
bind l select-pane -R

# resize panes like vim
# feel free to change the "1" to however many lines you want to resize by,
# only one at a time can be slow
bind < resize-pane -L 10
bind > resize-pane -R 10
bind - resize-pane -D 10
bind + resize-pane -U 10

# bind : to command-prompt like vim
# this is the default in tmux already
bind : command-prompt

#!/bin/bash

export MY_CARD="enp2s0"
tc qdisc add dev $MY_CARD root handle 1: htb
tc class add dev $MY_CARD  parent 1: classid 1:1 htb rate 400mbit
# 同时限制端口速度
tc filter add dev $MY_CARD parent 1: prio 1 protocol ip u32 match ip dst 0.0.0.0/0 match ip sport 80 0xffff flowid 1:1

#!/bin/bash

export MY_CARD="enp2s0"
echo 0x100001 >  /sys/fs/cgroup/net_cls/net_cls.classid
tc qdisc add dev $MY_CARD root handle 10: htb
tc class add dev $MY_CARD parent 10: classid 10:1 htb rate 400mbit
tc filter add dev $MY_CARD  parent 10: protocol ip prio 10 handle 1: cgroup

#!/bin/bash

export MY_CARD="enp2s0"
tc qdisc delete dev $MY_CARD root

#!/bin/bash

export MY_CARD1="enp2s0"
export MY_CARD2="ifb0"

modprobe ifb  numifbs=1
ip link set dev $MY_CARD2 up
tc qdisc add dev $MY_CARD1 handle ffff: ingress
tc filter add dev $MY_CARD1  parent ffff: protocol ip u32 match u32 0 0 action mirred egress redirect dev $MY_CARD2

#限制输出
tc qdisc add dev $MY_CARD1 root handle 1: htb default 10
tc class add dev $MY_CARD1 parent 1: classid 1:1 htb rate 50mbit ceil 50mbit burst 1m
tc class add dev $MY_CARD1 parent 1:1 classid 1:10 htb rate 50mbit

#限制输入
tc qdisc add dev $MY_CARD2 root handle 1: htb default 10
tc class add dev $MY_CARD2 parent 1: classid 1:1 htb rate 40mbit ceil 40mbit burst 1m
tc class add dev $MY_CARD2 parent 1:1 classid 1:10 htb rate 40mbit

#!/bin/bash

export MY_CARD1="enp2s0"
export MY_CARD2="ifb0"

tc qdisc delete dev $MY_CARD1 root
tc qdisc delete dev $MY_CARD2 root
tc qdisc delete dev $MY_CARD1 handle ffff: ingress

LimitNOFILE=65536
LimitMEMLOCK=infinity

# mount –o loop  XX.iso  /root/
# cd /root/Packages
# rpm -ivh createrepo-0.9.8-5.el6.noarch.rpm
# cd /root
# createrepo /root/       (表明把仓库文件放在该目录下)
# cd /etc/yum.repos.d
# cat /etc/yum.repos.d/mycdrom.repo
[Base]
name=RHEL7 ISO Base
baseurl=file:///mnt/         #mnt为mount的目录
enabled=1
gpgcheck=0
[root@localhost /]

# cd /etc/yum.repos.d/
# cp file.repo file.repo.bak
# cat file.repo
[file]  #最好和文件名保持一致
name=test  #这个随便写
baseurl=file:///mountdir   #这个目录很重要，跟iso文件下的repodata同一层目录
enabled=1
gpgcheck=0

# virt-what

# cat /proc/cpuinfo | grep hypervisor

# watch -d -n1 du -m file1      //-d表示显示后面命令执行的变化

# wget -m -np -p -k -L -P . https://repos.fedorapeople.org/repos/openstack/openstack-juno/epel-7/
# wget -m -np -p -k -L -P . https://repos.fedorapeople.org/repos/openstack/openstack-juno/epel-7/epel/
# wget -m -np -p -k -L -P . https://repos.fedorapeople.org/repos/openstack/openstack-juno/epel-7/repodata/

# find ./ | xargs dos2unix {}        --- {} 表示所有find到的文件
# ls | xargs -i mv {} {}.bak         --- -i 选项告诉 xargs 用每项的名称替换{}
# find -name ".svn" |xargs rm -rf

# xfsdump -f /mountdir/backup  -L lable  -M lable /dev/sda3
# xfsrestore -f /mountdir/backup  ./new_dir

# mount -o usrquota,grpquota  /dev/xxx  /mountdir
# xfs_quota -x -c 'limit bhard=500m someuser' /mountdir
# xfs_quota -x -c "report"
# repquota -ug /mountdir

# xfs_copy /dev/sdc1 /dev/sdc2

# xfs_freeze -f /mountdir    //暂停
# xfs_freeze -u /mountdir    //恢复

# xfs check /dev/sdc1