Hacking SteelSeries Engine 3 USB Mouse Under Linux

Feb 3, 2016
Technology

Background

Since SteelSeries Engine 3 USB mouse have only driver for Windows/MAC, I want to enable the changing color under Linux, following is the hacking steps.

Catching Packets

Using Wireshark for capturing the USB Packages of mouse, at the meantime, use another mouse for clicking the setting color area, to capture the setting color events, After this we sent the captured packets to Linux machine for analysing.

/images/2016_02_03_18_38_33_587x367.jpg

Setting Color

With the filter and continue for anlysing, found each setting step includes 3 steps.

Result:

44000000060000005c00000000000000db2a05007169cdb73c0000003c000000
44000000060000005c00000000000000db2a0500036a6db93c0000003c000000
44000000060000005c00000000000000db2a05005b3943ba3c0000003c000000
44000000060000005c00000000000000db2a05002b5930bb3c0000003c000000
44000000060000005c00000000000000db2a05005f51e1bb3c0000003c000000

Each time’s color listed as(R,G,B):

10ad73
2a10ad
ad8e10
ad3c10
ad109b

cleaning result:

7169cdb7
036a6db9
5b3943ba
2b5930bb
5f51e1bb

Seems no relationship? need to verify the usb protocol mechanism.

virtio-gpu working tips

Jan 31, 2016
Technology

System

Install Fedora 23, select fedora server and install the system, then using the lastest development kernel via:

$ curl -s https://repos.fedorapeople.org/repos/thl/kernel-vanilla.repo | sudo tee /etc/yum.repos.d/kernel-vanilla.repo
$ sudo dnf --enablerepo=kernel-vanilla-mainline update

Checking the running kernel via:

$ uname -r
4.5.0-0.rc1.git0.1.vanilla.knurd.1.fc23.x86_64

Running the system which have kernel version newer than 4.4 is the basis for enable the virt-io.

Install packages

$ sudo dnf install -y gcc zlib-devel glib2-devel pixman-devel libfdt-devel \ 
lzo-devel snappy-devel bzip2-devel libseccomp-devel gtk2-devel gtk3-devel \ 
gnutls-devel vte-devel SDL-devel librdmacm-devel libuuid-devel \ 
 libcap-ng-devel libcurl-devel ceph-devel libssh2-devel libaio-devel \ 
glusterfs-devel glusterfs-api-devel numactl-devel gperftools-devel \ 
 texinfo libiscsi-devel spice-server-devel libusb-devel usbredir-devel \ 
libnfs-devel libcap-devel libattr-devel

virglrenderer

coprs have the repository for this:
https://copr.fedorainfracloud.org/coprs/kraxel/

$ cd /etc/yum.repos.d/
$ sudo wget https://copr.fedorainfracloud.org/coprs/kraxel/virgl/repo/fedora-23/kraxel-virgl-fedora-23.repo

Install the virglrenderer via:

$ sudo dnf install virglrenderer

qemu

Git clone the source code:

$ git clone https://www.kraxel.org/cgit/qemu

Read Digest On KVM

Jan 26, 2016
Technology

Some Words

VMM: (Virtual Machine Monitor)
VMX: (Virtual Machine eXtensions): instructions on processors with x86 virtualization.

Virtualization software: is most often used to emulate a complete computer system in order to allow a guest operating system to be run, for example allowing Linux to run as a guest on top of a PC that is natively running a Microsoft Windows operating system (or the inverse, running Windows as a guest on Linux).

CPU Ring:
https://en.wikipedia.org/wiki/Protection_ring

/images/300px-Priv_rings.svg.png

VT-d, I/O Hardware Virtualization.
VT-c, Networking Hardware Virtualization.

Host kickstart file

Add following installation packages:

%packages
@virtualization
@Base
@Core
@additional-devel
@base
@large-systems
@storage-client-iscsi
@systgem-management-snmp
@virtualization
@virtualization-client
@virtualization-platform
@virtualization-tools
%end

Mouse On Windows Virtual Machine

Add twice the usb mouse:

<input type='tablet' bus='usb'

NUMA

Install the numa configuration tools via:

# apt-cache search numactl
numactl - NUMA scheduling and memory placement tool
# apt-get -y install numactl

Command: numactl --hardware, numastat, numastat -c qemu-kvm.

Check the numa banlancing policy via:

# cat /proc/sys/kernel/numa_balancing
0

echo 1 for open the auto balancing.

KSM, could merge the same memory page, even in different NUMA node.

# cat /sys/kernel/mm/ksm/merge_across_nodes 
1

CPU Binding

Use virsh vcpuinfo xx for displaying the VCPU/CPU corresponding relationship.

virsh # emulatorpin 79
emulator: CPU Affinity
----------------------------------
       *: 0-7

Change it dynamically:

virsh # emulatorpin 79 0-3 --live

virsh # emulatorpin 79
emulator: CPU Affinity
----------------------------------
       *: 0-3

Now you could check the result via virsh dumpxml xxx:

  <vcpu placement='static'>4</vcpu>
  <cputune>
    <emulatorpin cpuset='0-3'/>
  </cputune>

1-1 binding using virsh:

# virsh vcpupin 79 0 0    
# virsh vcpupin 79 1 1
# virsh vcpupin 79 2 2
# virsh vcpupin 79 3 3
# virsh dumpxml 79 | more
  <cputune>
    <vcpupin vcpu='0' cpuset='0'/>
    <vcpupin vcpu='1' cpuset='1'/>
    <vcpupin vcpu='2' cpuset='2'/>
    <vcpupin vcpu='3' cpuset='3'/>

Now view the vcpuinfo via:

# virsh vcpuinfo 79
VCPU:           0
CPU:            0
State:          running
CPU time:       9.2s
CPU Affinity:   y-------

CPU Hot-Plug-in

The cpu configuration info is listed as:

/images/2016_01_26_10_54_29_285x127.jpg

View the CPU infos via:

# cat /proc/interrupts 
           CPU0       CPU1

Change the CPUs to 3:

virsh # setvcpus 80 3 --live

Now in the vm the result should be(or detect it via cat /proc/cpuinfo) :

# cat /proc/interrupts 
           CPU0       CPU1       CPU2

CPU Working Mode

If we select the pass-through, then the cpuinfo should be:

# virsh dumpxml xxxxx
  <cpu mode='host-passthrough'>
  </cpu>
# cat /proc/cpuinfo
processor       : 1
vendor_id       : GenuineIntel
cpu family      : 6
model           : 58
model name      : Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz

If we select the host-model, will choose the most similar:
Or If we choose Copy host cpu mode, like following:
/images/2016_01_26_11_07_32_299x274.jpg

# cat /proc/cpuinfo
....
processor       : 1
vendor_id       : GenuineIntel
cpu family      : 6
model           : 42
model name      : Intel Xeon E312xx (Sandy Bridge)

Memory Balloon

Change the memory balloon to 1024 or 4096 via:

# virsh qemu-monitor-command PerfTune --hmp --cmd balloon 1024
# virsh qemu-monitor-command PerfTune --hmp --cmd info balloon
balloon: actual=1024
# virsh qemu-monitor-command PerfTune --hmp --cmd balloon 4096

Memory Limitation

Make configuration of the memory via:

virsh memtune PerfTune --hard-limit xxxxx --config
virsh memtune PerfTune --soft-limit xxxxx --config
virsh memtune PerfTune --swap-hard-limit xxxxx --config
virsh memtune PerfTune --min_guarantee xxxxx --config

–config, write to configuration xml –live, lively write –current ?

HugePage

Enable hugepage via:

# grep -i huge /proc/meminfo 
AnonHugePages:  12820480 kB
HugePages_Total:       0
HugePages_Free:        0
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB

Tips On Setup Mesos Cluster

Jan 18, 2016
Technology

Prerequisition

Install on Ubuntu14.04, so first we update to the latest version via:

$ sudo apt-get update && sudo apt-get upgrade -y

Prepare the repository of mesos via:

# sudo apt-key adv --keyserver keyserver.ubuntu.com --recv E56151BF
# DISTRO=$(lsb_release -is | tr '[:upper:]' '[:lower:]')
# CODENAME=$(lsb_release -cs)
# echo "deb http://repos.mesosphere.io/${DISTRO} ${CODENAME} main" | sudo tee /etc/apt/sources.list.d/mesosphere.list

mesos depends on java8, so we should install java8 on ubuntu machine via following command:

$ sudo apt-get install software-properties-common
$ sudo add-apt-repository ppa:webupd8team/java -y
$ sudo apt-get update
$ sudo apt-get install oracle-java8-installer

Installation

Linux Tips(4)

Jan 15, 2016
LinuxTips

1. Run ansible commands

Run commands in all hosts:

# ansible all -i inventory.ini -m command -u root --args "uptime"

2. mesos introduction

http://www.infoq.com/cn/articles/analyse-mesos-part-02

3. Limit ansible run hosts

# ansible-playbook -i inventory_mesos_cluster changehostname.yml -u root -k
-vvvv --list-hosts

playbook: changehostname.yml

  play #1 (master1): host count=1
    10.47.58.31

#  ansible-playbook -i
inventory_mesos_cluster changehostname.yml -u root -k -vvvv --limit="master1"

4. Configure the dhcp configuration of libvirtd

First edit the net configuration:

# virsh net-edit xxxxx

/images/2016_01_16_20_23_08_715x270.jpg

5. Copy items into clipboard in vim

Hit Ctrl+v to visual model, then select the items you want to copy, after select them, click "*y will copy whatever you selected into your clipbard.

Copy from clipboard—- simply hit p in command mode.

6. mesos.cli

When you meet no module named mesos, install it via pip:

$ pip install mesos.cli

7. Startdict In Command Line

$ sudo apt-get install -y sdcv
$ wget
https://web.archive.org/web/20140917131745/http://abloz.com/huzheng/stardict-dic/dict.org/stardict-dictd_www.dict.org_gcide-2.4.2.tar.bz2
$ sudo mkdir -p /usr/share/stardict/dic/
$ sudo tar xjvf stardict-dictd_www.dict.org_gcide-2.4.2.tar.bz2 -C /usr/share/stardict/dic

8. Golden Dict

Golden Dict.

9. Latest Info On OpenStack

https://mp.weixin.qq.com/s?__biz=MzA3MjkwMDY5OA==&mid=404253985&idx=1&sn=0d6c544dfb129e35bde7d19a0de8887b&scene=1&srcid=01267Etq7arAdYaFqbUG5BNa&pass_ticket=qT7Nk3zsTIegBKqnPTUL%2FTtS%2FMNDH%2F07Fz%2Bfua9RcTwSHVO5OLo5wDpfeb%2FBLCEH#rd

10. Quickly Configure vagrant machine

Via following you could get outside world:

ip route del default gw 10.0.2.2 dev enp0s3
ip a del 192.168.10.199/24 dev enp0s8
ip a add 192.168.10.199/16 dev enp0s8
ip route add default via 192.168.0.79 dev enp0s8

11. Change the default gateway On CentOS 7

Default gateway should go here:

$ cat /etc/sysconfig/network
# Created by anaconda
GATEWAY=192.168.0.79

And remove the origin default gateway by adding following definitions :

$ cat /etc/sysconfig/network-scripts/ifcfg-enp0s3 
# Generated by dracut initrd
NAME="enp0s3"
DEVICE="enp0s3"
BOOTPROTO=dhcp
# This one is not the default gw
DEFROUTE=no
# Do not override the dns
PEERDNS=no

Thus the default gateway won’t go from enp0s3, but from enp0s8, won’t configure the dns address to 10.0.x.x.

12. On VPNs

http://linsir.org/post/how_to_install_IPSec_IKEV2_base_on_strongswan_with_CentOS7
https://quericy.me/blog/512
https://quericy.me/blog/699
http://lifehacker.io/post/108814979111/%E5%9C%A8%E6%90%AC%E7%93%A6%E5%B7%A5%E7%9A%84centos7%E4%B8%8B%E6%90%AD%E5%BB%BAstrongswan%E5%AE%9E%E7%8E%B0%E5%9C%A8ios%E4%B8%8A%E6%8C%89%E9%9C%80%E8%BF%9E%E6%8E%A5vpn
https://raymii.org/s/tutorials/IPSEC_vpn_with_CentOS_7.html
https://linux.cn/article-5938-weibo.html

MMC snap-in:
https://technet.microsoft.com/en-us/library/cc722035.aspx

13. Use iptables On CentOS7

Use following steps for disable firewalld and use iptables.

$ systemctl stop firewalld
$ systemctl mask firewalld
$ yum install iptables-services
$ systemctl enable iptables
$ systemctl start iptables

14. Quickly Goes kernel configuration

When you want to configure the newer kernel source tree using your old kernel configuration, simply do following:

# yes "" | make oldconfig

15. iptables problem

After installing the newest kernel, I cannot use iptables, showing can't initialize iptables : table does not exist.

Solution: compile the modules again, select nat.

/images/2016_01_28_16_05_52_496x361.jpg

Selecting from:
Networking Support
Network Options
Network packet filtering framework(Netfilter)
IP: Netfilter Configuration

Then you should make modules_install under your kernel source building directory.

16. DistCC For Building Kernel DEB

On configurating distcc:
http://linuxdeveloper.blogspot.tw/2012/03/distributed-kernel-compilation-in.html

On building Linux kernel deb files:

http://www.cyberciti.biz/faq/debian-ubuntu-building-installing-a-custom-linux-kernel/

And:

https://help.ubuntu.com/community/Kernel/Compile

Actual command:

$ time sudo make -j12 CC=distcc
$ sudo MAKEFLAGS="CC=distcc" make-kpkg --rootcmd fakeroot --initrd --append-to-version=-suspend2 kernel-image kernel-headers kernel-source -j16

Really takes long time for building the kernel out, but the iptables won’t works.

17. dmenu On Ubuntu

dmenu is in the package of suckless-tools.

$ sudo apt-get install suckless-tools

18. Virtio-GPU How-to

https://www.kraxel.org/blog/2015/06/virtio-gpu-on-the-way-upstream/

20. Use Latest Dev Kernel On Fedora

Refers to http://fedoraproject.org/wiki/Kernel_Vanilla_Repositories

$ curl -s https://repos.fedorapeople.org/repos/thl/kernel-vanilla.repo | sudo tee /etc/yum.repos.d/kernel-vanilla.repo
$ sudo dnf --enablerepo=kernel-vanilla-mainline update

Fall back to the stable one:

$ sudo dnf --enablerepo=kernel-vanilla-stable update

21. Install grub on usb disk/ArchLinux

# chattr -i /boot/grub/i386-pc/core.img 
# grub-install --target=i386-pc --recheck --debug --force /dev/sdb
# chattr +i /boot/grub/i386-pc/core.img

22. fcitx-gtk3

Since now firefox using gtk3, so if you want to input chinese in firefox, simply install fcitx-gtk3 then you get fcitx working.

23. Polkit And Virt-manager

Problem:

$ virsh -c qemu:///system
error: failed to connect to the hypervisor
error: authentication failed: no agent is available to authenticate

Add the configuration for the polkit and restart the service:

$ sudo vim /etc/polkit-1/rules.d/49-org.libvirt.unix.manager.rules
polkit.addRule(function(action, subject) {
    if (action.id == "org.libvirt.unix.manage" &&
        subject.isInGroup("kvm")) {
            return polkit.Result.YES;
        }
});

And also you have to add your current user into the group of kvm:

$ sudo usermod -a -G kvm <user name>

Restar the polkit service via:

$ sudo systemctl restart polkit.service

24. Running tasks in byobu

http://superuser.com/questions/623432/transfer-current-command-to-a-detachable-session-tmux-screen

25. GPU Pass-Through

http://www.gitztalk.com/posts/2014/06/30/gaming-in-a-vm/

26. yaourt build error

Reason: gpg checking error, solution is:

$ proxychains4 gpg --recv-key  79BE3E4300411886

27. libvirtd and polkit

Bypass the password prompt:

https://wiki.archlinux.org/index.php/Polkit#Bypass_password_prompt

32. Set/Unset keyboard LED

Turn on/off the Scroll LED of the keyboard(USB):

xset led 3
xset -led 3

33. USB In a NutShell

http://www.beyondlogic.org/usbnutshell/usb1.shtml

34. Arduino USB Tutorial

http://codeandlife.com/2012/01/22/avr-attiny-usb-tutorial-part-1/

35. Auduino USB Project

https://www.obdev.at/products/vusb/projects.html

36. Detecting mouse events

Using evtest for detecting mouse events:

$ sudo apt-get install evtest
$ sudo evtest

37. SteelSeries Mouse (RAW) DEMO

https://www.youtube.com/watch?v=yvvybR6oyvs

38. USB Device Driver

http://blog.chinaunix.net/uid-20587912-id-2984380.html

http://www.wzona.info/2012/10/usb-duomenu-perdavimas-atmega.html

39. Reverse usb device driver

http://phoeagon.byethost15.com/2012/05/05/%e7%bb%99%e6%9d%82%e7%89%8c%e5%b9%bb%e7%81%af%e7%89%87usb%e9%81%a5%e6%8e%a7%e5%86%99linux%e9%a9%b1%e5%8a%a8-%e4%b8%8a/

http://www.phoronix.com/scan.php?page=news_item&px=MTEzODU

https://bbs.archlinux.org/viewtopic.php?id=187995

https://www.youtube.com/watch?v=GdvmsWnZkyc

https://learn.adafruit.com/hacking-the-kinect/more-kinect-information

https://www.linuxvoice.com/drive-it-yourself-usb-car-6/

Total Phase USB:

http://www.totalphase.com/products/beagle-usb12/

https://github.com/dmage/co2mon

40. v-usb tutorial

http://www.workinprogress.ca/v-usb-tutorial-software-only-usb-for-mega-tiny/

41. v-usb and Arduino

https://www.hackster.io/rayburne/arduino-to-excel-using-v-usb-cbf701

http://www.geek-workshop.com/forum.php?mod=viewthread&tid=8578&highlight=v-usb

http://coopermaa2nd.blogspot.tw/2011/10/v-usb-examples-for-arduino.html

http://www.geek-workshop.com/thread-1137-1-1.html

http://www.geek-workshop.com/forum.php?mod=viewthread&tid=15114&highlight=v-usb

42.Set Timezone of the ArchLinux

Change from UTC to Asia/Shanghai:

$ timedatectl set-timezone Asia/Shanghai

43. Empty all of the bash history

Empty the bash history via:

$ rm -f ~/.bash_history

44. Specify qemu-binary in Packer.io

Edit the json files:

"builders":
[
{
"type": "qemu",
"qemu_binary" : "/usr/libexec/qemu-kvm.sh",

45. apprmor.d

I modified /etc/apparmor.d/abstractions/libvirt-qemu to include the
backing store directory

46. Recover UEFI bootloader

After remove the mainline linux kernel, the archlinux is using the default kernel, but the UEFI bootloader didn’t notice this, following are the steps for recover the UEFI bootloader.

grub-install --target=x86_64-efi --efi-directory=/boot/EFI   --bootloader-id=arch_grub --recheck
cat ./EFI/loader/entries/arch.conf

Change the items into initramfs-linux.

If you cannot login to the system, you could start the machine via USB disk or installation media, using arch-chroot /mnt/ /bin/bash for login to the chroot system, then do the above operations.

47. bonding

http://sanswers.com/tube/wotC5GZ2FV0/bonding-eth0-and-wlan0-on-arch-linux

48. Fix currpted zsh history

history corrupted.

$ mv .zsh_history .zsh_history_bad
$ strings .zsh_history_bad > .zsh_history
$ fc -R .zsh_history

49. pulp

Using pulp for managing the repositories of RPM/Docker, etc.

50. Chromium flash

Install chromium-pepper-flash in aur.

51. Install xfce4 on CentOS

Install xfce in epel repository via:

# yum --enablerepo=epel -y groups install "Xfce"

52. LED controller

http://www.seeedstudio.com/recipe/402-smart-power-outlet.html

53. Build php envs

https://medium.com/dev-tricks/apache-and-php-on-docker-44faef716150#.c8bguolj0

54. handle docker changes

http://dbaron.org/linux/handle-dock-change.py

55. python detection of usb storage

https://linuxmeerkat.wordpress.com/2014/11/12/python-detection-of-usb-storage-device/
d-feet for debugging of dbus..

Install gvfp-mtp, then you could get your nautillus have the mtp device support.

Using mtp-detect for detecting the equipments and mtp-connect for connecting the device.

57. Virtualbox Driver Issue

After upgrading the system, the virtualbox won’t start the machine, this is because we didn’t install the kernel header, thus the dkms won’t be run after system upgrading. Install kernel-headers:

$ sudo pacman -S linux-headers
$ sudo /sbin/rcvboxdrv setup

58. Creation tools

https://linux.cn/article-7072-1.html

59. rvm reinstall issue

openssl load error:

$ rvm pkg install openssl
$ rvm install 2.2.1  --with-openssl-dir=$HOME/.rvm/usr
$ proxychains4 gem update bundler

Then you can continue to use your octopress.

60 Install go on ArchLinux

$ sudo pacman -S go
$ mkdir ~/go
$ vim ~/.zshrc
export GOPATH=~/go
export PATH=$PATH:~/go/bin

61. Packer Development Version

The steps on building packer on Ubuntu:

$ sudo add-apt-repository ppa:ubuntu-lxc/lxd-stable
$ sudo apt-get update
$ sudo apt-get install golang
$ mkdir -p $HOME/Documents/golang
$ export GOPATH=$HOME/Documents/golang
$ export GO15VENDOREXPERIMENT=1
$ export PATH=$PATH:$GOPATH/bin
$ go get github.com/mitchellh/packer
$ cd $GOPATH/src/github.com/mitchellh/packer
$ sudo chown -R dash /home/dash/
$ make

bitnami

62. Install add-apt-repository command

add-apt-repository missing:

$ sudo apt-get install software-properties-common

63. git checkout specified tags

For checkout specified tag:

$ git tag -l
.....
.....
xxyy
$ git checkout tags/xxyy -b xxyy_local

64. Nested kvm On ArchLinux

Enable the nested kvm for ArchLinux via following steps:

➜  ~ systool -m kvm_intel -v | grep nested
    nested              = "N"
➜  ~ modprobe -r kvm_intel
modprobe: ERROR: could not remove 'kvm_intel': Operation not permitted
➜  ~ sudo modprobe -r kvm_intel
➜  ~ sudo modprobe kvm_intel nested=1
➜  ~ sudo vim /etc/modprobe.d/modprobe.conf
options kvm_intel nested=1
➜  ~ systool -m kvm_intel -v | grep nested
    nested              = "Y"

65. Failed to build rubygem

Issue:

Unable to install gem - Failed to build gem native extension - cannot load
such file — mkmf (LoadError)

Solved by: sudo apt-get install -y ruby-dev.

66. xe-tools location

Loation for finding xe-tools:

# pwd
/opt/xensource/packages/iso
# ls
XenCenter.iso  xs-tools-6.5.0-20001.iso  xs-tools-6.5.0.iso

67. Qemu Tunnel Types

http://linuxsimba.com/qemu-tunnel-types/

68. zsh history

Error message is zsh: corrupt history file /home/myusername/.zsh_history.

Solved by:

➜  ~ mv .zsh_history .zsh_history_bad
➜  ~ strings .zsh_history_bad > .zsh_history
➜  ~ fc -R .zsh_history

69. virsh priviledge In Ubuntu

When met following issue, solved via add current user to libvirtd and kvm, relogin again then issue would be solved:

Error while connecting to libvirt: Error making a connection to libvirt URI
qemu:///system?no_verify=1&keyfile=/home/dash/.ssh/id_rsa:
Call to virConnectOpen failed: Failed to connect socket to
'/var/run/libvirt/libvirt-sock': Permission denied

Solution :

$ sudo usermod -a -G kvm dash
$ sudo usermod -a -G libvirtd dash

70. Vagrant ext vars

http://stackoverflow.com/questions/23008367/ansible-with-vagrant-read-inventory-from-vagrantfile-extra-vars

71. rootpasswd in Kickstart

Formats, and to generate the encrypted format.

rootpw "password here"
rootpw --iscrypted password_hash
$ openssl passwd -1 "password here"

72. On Vagrant Xenserver

To build Xenserver vagrant box in packer:
https://github.com/imduffy15/packer-xenserver

Possible usable vagrant box(For Xenserver):
https://vagrantcloud.com/duffy/boxes/xenserver

Remote provisioning to a xenserver hypervisor:
http://serverfault.com/questions/631837/remote-automated-provisioning-to-a-xenserver-hypervisor

Ansible and Xen:
http://sharknet.us/2013/12/13/276/

Vagrant and XenServer:
https://github.com/jonludlam/vagrant-xenserver

73. Tips on Xenserver In Vagrant

Mac address:

# vim /etc/sysconfig/network-scripts/interface-rename-data/static-rules.conf
eth0:mac = "xxxxxxxxx"
# interface-rename --dry-run --reset-to-install

Then you could reset all of your configuration into the initial status.

74. oh-my-vagrant

https://github.com/purpleidea/oh-my-vagrant

75. Detect System

http://unix.stackexchange.com/questions/89714/easy-way-to-determine-virtualization-technology

Use dmidecode.

76. git remove untracked files

Following commands will remove the untracked files in .gitignore.

$  git rm --cached .vagrant
$  git rm --cached -r .vagrant
$  git rm -r --cached . 
$  git add .
$  git commit -m "Added with gitignored"
$  git push origin master

77. node mcu good example

http://bbs.nodemcu.com/t/nodemcu/1147

78. 8723ae issue

Do following to make the rtl8723awe working more effeciently.

$ vim  /etc/modprobe.d/rtl8723ae.conf
options rtl8723ae fwlps=0

79. PDF Chinese

Poppler-data will enable chinese support.

$ sudo pacman -S poppler-data

80. Join multiple lines with comma

abc.txt should remove the end enter and replaced with comma.

$ cat abc.txt | tr '\n' ','

Refers to:
http://blog.irreverence.co.uk/?p=209

81. Shrink vhd file

In XenServer vms:

$ cat /dev/zero > zero.dat ; sync ; sleep 1 ; sync ; rm zero.dat

82. VHD File Compact

shirinking the vhd file via:

$ VBoxManage clonehd target.vhd cloned.vhd
$ VBoxManage modifyhd cloned.vhd --compact

83. 1602 And RPI

http://www.raspberrypi-spy.co.uk/2015/05/using-an-i2c-enabled-lcd-screen-with-the-raspberry-pi/
http://raspberrypi.stackexchange.com/questions/28991/how-can-i-use-a-lcd-display-with-a-i2c-adapter

84. CPU Frequency

Install and enable the service of cpupower via:

$ sudo pacman -S cpupower
$ sudo systemctl enable cpupower.service
$ sudo systemctl start cpupower.service

configure the cpupower parameters via:

$  cat /etc/default/cpupower   
# Define CPUs governor
# valid governors: ondemand, performance, powersave, conservative, userspace.
governor='performance'

Some useful commands should be like:

$ sudo cpupower frequency-set -f  3.06
$ cpupower frequency-info
$ watch grep \"cpu MHz\" /proc/cpuinfo

85. Gmail Mutt

https://www.linux.com/community/blogs/133-general-linux/850945-setup-mutt-with-gmail-on-centos-and-ubuntu

86. Fake Video

http://www.atechnote.com/2014/11/create-fake-webcam.html
https://developer.ubuntu.com/en/snappy/start/

87. Way Of Snappy Extend

http://askubuntu.com/questions/577105/is-there-a-way-to-add-repo-to-snappy-ubuntu-core

88. pl2802 driver

You probably have a counterfeit adapter. It won’t work with the updated driver. You need to find the 3.2.0.0 driver and use it instead. You can find it here http://www.miklor.com/COM/UV_Drivers.php

83. collectd On ArchLinux

Install collectd via:

$ sudo pacman -S rrdtool net-snmp liboping collectd

84. gem path

Use gem env for detecting the system variables, some variables should be added into system path.

85. Vagrant and packer.io

http://boxupp.com/
http://phansible.com/
https://puphpet.com/#
getprotobox.com/
http://www.sitepoint.com/5-easy-ways-getting-started-php-vagrant/
http://rove.io/

86 Install latest ansible

Install the latest ansible on Ubuntu:

$ sudo apt-get update
$ sudo apt-get install software-properties-common
$ sudo apt-add-repository ppa:ansible/ansible

87. Packer And Ansible

http://www.jeffgeerling.com/blog/server-vm-images-ansible-and-packer

88. Vagrant issue

Problem is:

sudo vagrant up
Bringing machine 'tunirserver' up with 'libvirt' provider...
/usr/share/gems/gems/fog-1.23.0/lib/fog/libvirt/requests/compute/list_volumes.rb:32:in `info': Call to virStorageVolGetInfo failed: Storage volume not found: no storage vol with matching path '/tmp/orbit-kdas' (Libvirt::RetrieveError)