Linux使用技巧汇总

Debian是我日常使用的桌面系统，这里记录了我在使用Debian和其他Linux时所有的问题和解决办法，以及一些其他的心得体会。
向Debian致敬！

找回桌面系统关机按钮

在/etc/polkit-1/localauthority/50-local.d/新建文件50-admin.pkla,写入如下内
容：

    [disable suspend]   
    Identity=unix-user:*   
    Action=org.freedesktop.upower.suspend   
    ResultAny=no   
    ResultInactive=no   
    ResultActive=no   
    [disable hibernate]   
    Identity=unix-user:*   
    Action=org.freedesktop.upower.hibernate   
    ResultAny=no
    ResultInactive=no   
    ResultActive=no

无线不能使用的解决方法

安装rfkill工具

    #apt-get install rfkill 

then:

    #rfkill list all 

查看网卡设备的状态如下

    0: dell-wlan: Wireless LAN   
    Soft blocked: no   
     Hard blocked: no   
    1: phy0: Wireless LAN   
    Soft blocked: no   
    Hard blocked: no

根据软件或者硬件的状态解锁

wireshark普通用户权限

    $ sudo groupadd wireshark 
    $ sudo usermod -a -G wireshark YOUR_USER_NAME 
    $ sudo chgrp wireshark /usr/bin/dumpcap 
    $ sudo chmod 750 /usr/bin/dumpcap 
    $ sudo setcap cap_net_raw,cap_net_admin=eip /usr/bin/dumpcap 
    $ sudo getcap /usr/bin/dumpcap 

Adobe flash player的正确安装姿势

首先下载flash player，保存为flash.tar.gz
then:

    tar -zxvf flash.tar.gz
    mv usr/* /usr/
    mv libflashplayer.so /usr/lib/mozilla/plugins/

重启浏览器即可

解决Debian8 pptp不能连接的问题

报错内容：(/var/log/syslog)

    Sep 15 14:58:21 debian NetworkManager[13550]: ** Message: pppd started with pid 14188
    Sep 15 14:58:21 debian pppd[14188]: Plugin /usr/lib/pppd/2.4.6/nm-pptp-pppd-plugin.so loaded.
    Sep 15 14:58:21 debian NetworkManager[13550]: Plugin /usr/lib/pppd/2.4.6/nm-pptp-pppd-plugin.so loaded.
    Sep 15 14:58:21 debian NetworkManager[13550]: ** Message: nm-pptp-ppp-plugin: (plugin_init): initializing
    Sep 15 14:58:21 debian pppd[14188]: pppd 2.4.6 started by root, uid 0
    Sep 15 14:58:21 debian NetworkManager[13550]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 3 / phase 'serial connection'
    Sep 15 14:58:21 debian pppd[14188]: Using interface ppp0
    Sep 15 14:58:21 debian pppd[14188]: Connect: ppp0 <--> /dev/pts/0
    Sep 15 14:58:21 debian NetworkManager[13550]: Using interface ppp0
    Sep 15 14:58:21 debian NetworkManager[13550]: Connect: ppp0 <--> /dev/pts/0
    Sep 15 14:58:21 debian NetworkManager[13550]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 5 / phase 'establish'
    Sep 15 14:58:21 debian NetworkManager[13550]: <info> (ppp0): new Generic device (driver: 'unknown' ifindex: 57)
    Sep 15 14:58:21 debian NetworkManager[13550]: <info> (ppp0): exported as /org/freedesktop/NetworkManager/Devices/15
    Sep 15 14:58:21 debian NetworkManager[13550]: <info> devices added (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
    Sep 15 14:58:21 debian NetworkManager[13550]: <info> device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found.
    Sep 15 14:58:52 debian pppd[14188]: LCP: timeout sending Config-Requests
    Sep 15 14:58:52 debian pppd[14188]: Connection terminated.
    Sep 15 14:58:52 debian avahi-daemon[588]: Withdrawing workstation service for ppp0.
    Sep 15 14:58:52 debian NetworkManager[13550]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 11 / phase 'disconnect'
    Sep 15 14:58:52 debian NetworkManager[13550]: <info> devices removed (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
    Sep 15 14:58:52 debian pptp[14193]: nm-pptp-service-14185 warn[decaps_hdlc:pptp_gre.c:216]: pppd may have shutdown, see pppd log
    Sep 15 14:58:52 debian pppd[14188]: Modem hangup
    Sep 15 14:58:52 debian pppd[14188]: Exit.
    Sep 15 14:58:52 debian NetworkManager[13550]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 1 / phase 'dead'
    Sep 15 14:58:52 debian NetworkManager[13550]: ** Message: nm-pptp-ppp-plugin: (nm_exit_notify): cleaning up
    Sep 15 14:58:52 debian NetworkManager[13550]: ** (nm-pptp-service:14185): WARNING **: pppd exited with error code 16

依次输入如下命令：

    modprobe nf_nat_pptp
    modprobe nf_conntrack_pptp
    modprobe nf_conntrack_proto_gre

下次启动还会失效，所以要编辑/etc/modules-load.d/modules.conf文件，添加如下三行：

    nf_nat_pptp
    nf_conntrack_pptp
    nf_conntrack_proto_gre

正确安装ruby RVM的方法

    curl -sSL https://get.rvm.io | bash -s stable

减少开机等待时间

• 减少grub等待时间：
  修改/etc/default/grub，将

GRUB_TIMEOUT=5

改为 (grub等待超时改成1秒)：

GRUB_TIMEOUT=1

然后

# update-grup

• 减少开关机超时
  修改/etc/systemd/system.conf，修改开关机超时时间为5s：

DefaultTimeoutStartSec=5s
DefaultTimeoutStopSec=5s

重启

使用随机MAC地址

出于隐私需求，不想暴露真实mac地址，把下面这个脚本的内容加入/etc/init.d，就可以在每次开机的时候为网卡随机设置一个mac地址。

#!/bin/bash
#Chorder
#2016/12/08
    
mhash=`date +%s|md5sum`

ifconfig eth0 down
ifconfig eth0 hw ether `echo ${mhash:$((RANDOM % 13)):2}:\
${mhash:$((RANDOM % 13)):2}:${mhash:$((RANDOM % 13)):2}:\
${mhash:$((RANDOM % 15)):2}:${mhash:$((RANDOM % 15)):2}:\
${mhash:$((RANDOM % 15)):2} `
ifconfig eth0 up

ifconfig wlan0 down
ifconfig wlan0 hw ether `echo ${mhash:$((RANDOM % 13)):2}:\
${mhash:$((RANDOM % 13)):2}:${mhash:$((RANDOM % 13)):2}:\
${mhash:$((RANDOM % 15)):2}:${mhash:$((RANDOM % 15)):2}:\
${mhash:$((RANDOM % 15)):2} `
ifconfig wlan0 up

gnome删除多余菜单文件夹

gsettings set org.gnome.desktop.app-folders folder-children ['']

效果是去掉无用的菜单分类文件夹

CentOS删除旧内核

for k in `rpm -qa | grep kernel |grep -v \`uname -r\``;do yum remove $k;done

鼠标滚轮方向调整

~/.Xmodmap

如果想要鼠标逆序滚动，就将其中的内容改为

pointer = 1 2 3 4 5 6 7 8 9 10 11 12

否则，就将内容改为：

pointer = 1 2 3 5 4 6 7 8 9 10 11 12

4和5代表的是鼠标滚轮方向的映射。

Debian9 GNOME 允许root登录

修改三个文件：

• /etc/gdm3/daemon.conf
  在Security节，加入

AllowRoot=true

• /etc/pam.d/gdm-password
  注释掉

auth required pam_succeed_if.so_user != root quiet_success

• /etc/pam.d/gdm-autollgoin
  注释掉

auth required pam_succeed_if.so_user != root quiet_success

重启。