TurnToJPG -->

1. Build maven project

For building the class, do mvn compile, for building the jar file, do mvn package, then you could get the jar under the target folder.

2. sed replace

via following commands:

# sed s/</home/dash/docker-compose.yml

3. get ip for ubuntu

Ubuntu 14.04 ~ 18.04, via following command:

hostname -I | awk '{print $1}'

4. view systemd logs

via following command:

# journalctl -u service-name.service -b

5. Disable unattended upgrades

Under Ubuntu18.04/16.04, could do :

# systemctl disable unattended-upgrade.service

6. rhel subscription

Via following steps:

sudo subscription-manager remove --all
sudo subscription-manager unregister
sudo subscription-manager clean

Now re-register the system, attach the subscriptions - execute these commands :

sudo subscription-manager register
sudo subscription-manager refresh
sudo subscription-manager attach --auto

Here are the commands to see which repos are enabled and what can be added :

Execute sudo subscription-manager repos --list-enabled to see all actually enabled subscriptions.
Execute sudo subscription-manager repos --list to see all subscriptions that are available for you.
Execute sudo subscription-manager repos --enable <repo> if you want to add additional repos.

7. anaconda issue

anaconda build rhel7 custom image Issue:

# dracut module 'anaconda' cannot be found or installed

how to solve?

8. kismatic reset


./kismatic reset

9. kubernetes pkgs

Install via:

# vim /etc/yum.repos.d/kubernetes.repo

10. samba in ArchLinux

# pacman -S samba
# wget;a=blob_plain;f=examples/smb.conf.default;hb=HEAD
# cp /etc/samba/smb.conf
# vim /etc/samba/smb.conf
   log file = /var/log/samba/%m.log
   comment = Mary's and Fred's stuff
   path = /var1/Nov14
   valid users = dash
   public = no
   writable = yes
   printable = no
   create mask = 0765
# systemctl enable smb
# systemctl enable nmb
# systemctl start smb
# systemctl start nmb

11. tar with pigz

With pigz compression:

tar cf - paths-to-archive | pigz -9 -p 32 > archive.tar.gz

12. tips for centos

  1. install from iso
  2. sed the ip address.(isomaster)
  3. pigz package needed to be installed first. (isomaster)

13. tmpfs for debian

via :

# vim /etc/fstab

tmpfs	/tmp	tmpfs	nodev,nosuid,size=8G 0	0

14. kong ingress configuration

Rewrite ingress rulers:

apiVersion: extensions/v1beta1
kind: Ingress
  name: anagram.api
  annotations: "/"
  - host: anagram.api
      - path: /external
          serviceName: anagram-svc
          servicePort: 80
kind: KongIngress
  name: anagram.api
  path: /
  strip_path: true

15. Auto Restart pdnsd

The script for start pdnsd:

# cat /bin/ 
    touch /tmp/aaa.txt
    if [[ $(ps -ef | grep -v grep | grep pdnsd) ]]; then
    	echo "pdnsd alive">/tmp/aaa.txt
    	echo "not alive">/tmp/aaa.txt
    	systemctl start pdnsd

Add this script into crontab:

# crontab -e
@reboot sleep 60 && /bin/

16. python simple http server

python 3 syntax:

python -m http.server 8000

17. cnpm install error

As normal user, you didn’t have the priviledge for making soft link for cnpm.

As rooot user, do following:

$ sudo npm cache clean --force
$ sudo npm install -g cnpm --registry=
$ which cnpm

18. dnscrypt

start via, better enable it:

sudo systemctl start dnscrypt-proxy.service

19. Ubuntu 18.04 vnc

Via following steps:

install these packages

# apt-get install gnome-panel gnome-settings-daemon metacity nautilus gnome-terminal
and use this xstartup file



[ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup
[ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources
xsetroot -solid grey
vncconfig -iconic &

gnome-panel &
gnome-settings-daemon &
metacity &
nautilus &
gnome-terminal &

But you will add some tips:

$ vim /usr/bin/gnome-panel-delay 
sleep 4 && gnome-panel

Replace gnome-panel with gnome-panel-delay.

20. uefi for archlinux qemu

Install via:

$ sudo pacman -S ovmf
$ sudo vim /etc/libvirt/qemu.conf
nvram = [
$ sudo systemctl restart libvirtd

21. unlock proxmox

via following command:

# qm unlock vm_id

22. Back to Work

Edit /etc/systemd/network/, change the ip address, then restart the networkd service via:

# systemclt restart systemd-networkd.service

Then your briged br0 will turn back to the ip address you just changed.

23. Debian upgrade kernel

Via following commands:

# echo "deb stretch-backports main" | tee -a /etc/apt/sources.list > /dev/null
# apt-get update
# apt-cache search linux-image
# apt-get -t stretch-backports install linux-image-4.11.0-0.bpo.1-amd64

24. samba issue

From samba 4.8, the smbd, changed to smb, nmbd changed to nmb, so systemctl will changd to smb/nmb

25. unzip iconv

Chinese unzip:

$ unzip-iconv
$ unzip -O cp936

thus you will get the chinese coded file extracted.

26. Quickly Setup NodeJS Dev

In Conoha:

# docker run -it -p 5000:5000 ubuntu:latest /bin/bash
# apt-get update
# apt-get -y install vim
Change to
# apt-get update
# apt-get install -y nodejs npm
# cd ~
# mkdir Code
# cd Code
# mkdir node
# npm config set prefix=$HOME/node
# export PATH=$HOME/node/bin:$PATH
# npm install -g express
# npm install -g express-generator
# which express
# exporess defcon
# cd defcon/
# npm install -d
# npm install express  
# npm install -d

You should follow

Install with ejs template enabled:

# express -v ejs dash

27. registry setting(insecure)

Xenial , via:

Edit /etc/docker/daemon.json and update the key "insecure-registries".
        "insecure-registries" : [""]

28. paccache Saveing

Take care the directory size:

# pacman du -hs pkg 
31G	pkg
# pacman du -hs pkg 
9.4G	pkg
# pacman du -hs pkg 
4.1G	pkg

By following command you could saving the disk space(keep 3 or keep 1):

# sudo paccache -r -k 3
# sudo paccache -r -k 1 

29. kvm/vmware issue

kvm will be black-listed via vmware, solved via:

# cat /etc/modprobe.d/vmware.conf 
blacklist kvm
blacklist kvm-amd   # For AMD CPUs
blacklist kvm-intel # For Intel CPUs

Uninstall vmware via:

# vmware-installer -l
Product Name         Product Version     
==================== ====================
# vmware-installer -u vmware-workstation --required

Remove the service:

# rm /etc/systemd/system/vmware.service
# rm /etc/systemd/system/vmware-usbarbitrator.service

30. ansible for installing nfs-client

Install methods:

# apt-get install nfs-common
# vim local.ini
# ansible-playbook -i local.ini nfsclient.yaml --extra-vars "@roles/nfs-client/defaults/all.yaml"

31. chartmuseum

Delete and upload again:

#  curl -X DELETE
# curl --data-binary "@gitlab-runner-0.1.31.tgz"

32. docker volume rm

Via following command:

# docker volume ls | sed -n '1!p' |awk {'print $2'} | xargs -I % docker volume rm %

33. Generate crt/key in one line

Via following command:

# openssl req -new -newkey rsa:4096 -days 365 -nodes -x509     -subj "/C=US/ST=Denial/L=Springfield/O=Dis/"     -keyout  -out

34. Ubuntu Server GUI

Install tasksel via:

# apt-get install -y tasksel
# tasksel --list

Install Ubuntu mate core via:

# tasksel install ubuntu-mate-core
# service lightdm start

Or Ubuntu/xubuntu-core/Lubuntu-core, etc, you could choose from the tasksel list.

35. vncserver

For ArchLinux:

#exec startxfce4
exec startlxde

36. Internet Sharing

For ArchLinux, 2 cards, enp0s29u1u2u7 is the card for connecting the internet, while the enp0s29u1u2u6 is the card for intranet. :

➜  ~ sudo iptables -t nat -A POSTROUTING -o enp0s29u1u2u7 -j MASQUERADE
➜  ~ sudo iptables -A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
➜  ~ sudo iptables -A FORWARD -i enp0s29u1u2u6 -o enp0s29u1u2u7 -j ACCEPT

37. time-sync in archlinux

ArchLinux ntp date.

# vim  /etc/systemd/timesyncd.conf
# sudo systemctl enable systemd-timesyncd
# timedatectl show-timesync --all

38. Combine pdf

The filename contains Chinese, so I have to do like following:

$ ls -tr *.pdf | awk -v q="'" {'print q$0q'}>list.txt

Then edit the list.txt


Then your generated Combine.

$ pdfunite in-1.pdf in-2.pdf in-n.pdf out.pdf

Your generated out.pdf contains all of the pdfs.

39. crontab and notify-send

Create /bin/ for getting the DBUS Session bus address:


touch $HOME/.dbus/Xdbus
chmod 600 $HOME/.dbus/Xdbus
env | grep DBUS_SESSION_BUS_ADDRESS > $HOME/.dbus/Xdbus
echo 'export DBUS_SESSION_BUS_ADDRESS' >> $HOME/.dbus/Xdbus

On Awesome startup, use run_once function for calling it:

$ vim ~/.config/awesome/rc.lua

Now in your crontab task you have to write like following:

$ crontab -l
10 9-18 * * * /bin/
$ cat /bin/ 
    + if [ -r "$HOME/.dbus/Xdbus" ]; then
    +   . "$HOME/.dbus/Xdbus"
    + fi
    filecontent=`cat $filename`
    #### Until you click it, you won't get this window vanish #####
    notify-send -u critical -t 0 "$current_time, Stand UP, Boy" "$filecontent"

Now your notify-send will run properly.

40. unxz

Use unxz for uncompress xz compressed file.

41. ansible execute time

Add following configurations to ansible.cfg:

callback_whitelist = profile_tasks, timer

42. echo server

Run python echo server under kubernetes via:

# kubectl run myecho --image=echoserverpy:latest --replicas=3
# kubectl expose deployment myecho --port=31113

Edit for exposing UDP 31113 Port:


Add NodePort definition:


43. reconfigure keyboard

reconfigure keyboard on ubuntu is :

# sudo dpkg-reconfigure keyboard-configuration

44. raid issue


#/opt/MegaRAID/MegaCli/MegaCli64 -CfgLdDel -L1 -a0


MegaCli -LDInfo -LALL -aAll 【显示所有逻辑磁盘组信息】
MegaCli -PDList -aAll 【显示所有的物理信息】

45. vagrant-libvirt

Install via:

# yaourt vagrant-libvirt
# vagrant plugin install /opt/vagrant/embedded/gems/cache/vagrant-libvirt-0.0.45.gem
# vagrant plugin install vagrant-mutate
#  vagrant plugin list
vagrant-libvirt (0.0.45, global)
  - Version Constraint: 0.0.45
vagrant-mutate (1.2.0, global)

After upgrading, do following:

# vagrant plugin install /opt/vagrant/embedded/gems/cache/vagrant-libvirt-0.0.45.gem
# vagrant plugin install vagrant-mutate
# yaourt vagrant-libvirt

Then all of your plugins will work properly.

46. apt auto update disable

disable via:

systemctl stop apt-daily.timer
systemctl disable apt-daily.timer
systemctl disable apt-daily.service
systemctl stop apt-daily-upgrade.timer
systemctl disable apt-daily-upgrade.timer
systemctl disable apt-daily-upgrade.service

systemctl disable --now apt-daily{,-upgrade}.{timer,service}

47. openssl inspect lifetime of crt

Via following commands:

openssl x509 -in server.crt -noout -dates

48. Vagrant issue

Vagrant-libvirt, sometimes you have to manually build the ruby-libvirt plugin, and copy the correspoding so file into the /opt/vagrant

49. wrapped lines in vim

via following commands:

First set your vim so that it understands that you want 80 characters:

:set tw=80
then, hilight the line:

and make vim reformat it:


51. format several disk

Using following command:

set -e
set -x
for i in b c d e f g h i j k l; do
sudo fdisk -u /dev/vd${i}<<EOF


This command will format several disks, as you like.

52. Auto Change password

Change password via following commands:

$ openssl passwd -1 -salt 5RPVAd clear-text-passwd43


Then, copy the encrypted string to usermod. Make sure to wrap it with single quote.

$ usermod -p '$1$5RPVAd$vgsoSANybLDepv2ETcUH7.' root

Check it out in shadow file.

$ grep root /etc/shadow

53. rsync sync repo

syncing the ceph repository via following command:

# rsync -av --exclude "ceph-debuginfo" rsync://  `pwd`
# rsync -av --exclude "ceph-debuginfo" rsync://  ./

54. pool-start

Via following command you could view and start the virsh pool:

$ sudo virsh pool-list --all
$ sudo virsh pool-start vagrantpool

55. minikube start specify cpu/mem/disk

via following method:

# minikube start --cpus 4 --memory 8192 --disk-size 60g

56. Combine lines under linux

Via tr command you could combine several lines into one line:

# some output | tr '\n' ','

Replace the comma with some other characters.

57. prometheus for k8s



58. virtualbox tips

Debian’s virtualbox, 5.2 conflicts with kernel 4.17.0-9.bpo.1-amd64

59. libvirt’s bus issue

Changes to virtio bus:

   :file, :device => "hd#{driverletters[d]}", :path => "glusterdisk-#{i}-#{d}-#{DISK_UUID}.disk", :size => $kube_node_instances_with_disks_size, :bus => "virtio"

60. Minimum glusterfs nodes

Comment the replcas items. and set the volume type to None:

  volumetype: "none"
#  volumetype: "replicate:{{ hostvars[groups['glusterfs'][0]].replicate }}"

Or using heketi for creating the volume:

heketi-cli volume create -size=100 -durabilty=none

61. history without number

history without number using cut.

 history | cut -c 8-

62. tr replace newline

Via following commands:

#  tr '\r\n' ' '

63. two file difference

via grep command you could do this:

# git -v -f before.txt after.txt

64. vimdiff tips

vimdiff tips.

do (diff obtain) and dp (diff put) is what you need. Here is a small list of other helpful normal mode commands in this context.

]c               - advance to the next block with differences
[c               - reverse search for the previous block with differences
do (diff obtain) - bring changes from the other file to the current file
dp (diff put)    - send changes from the current file to the other file
zo               - unfold/unhide text
zc               - refold/rehide text
zr               - unfold both files completely
zm               - fold both files completely

65. pactree

Using pactree for viewing the dependencies:

# sudo pacman -S pacman-contri
# pactree xxxx

Using -d(1~n) could viewing the depth of the dependencies.

66. wifi list

unblock the wifi via following commands:

$rfkill list all
0: hp-wifi: Wireless LAN
	Soft blocked: yes
	Hard blocked: no
1: phy0: Wireless LAN
	Soft blocked: yes
	Hard blocked: yes

$sudo rfkill unblock all

67. sed disable swap

edit /etc/fstab via:

# sudo sed -i '/ swap / s/^/#/' /etc/fstab

68. python split

For using them in ambari-k8s, do following:

>>> long='nodes-1:;nodes-2:;nodes-3:'
>>> map={}
>>> key=[]
>>> for i in long.split(";"):
...   key.append(i.split(":")[0])
...   map[i.split(":")[0]]=i.split(":")[1]
>>> for i in key:
...   print(i)
>>> for i in key:
...   print(i)
...   print(map[i])

69. proxmox Configuration

For AI project, do following:

# vim /etc/network/interfaces
auto lo
iface lo inet loopback

auto eno1
#real IP address
iface eno1 inet static

auto vmbr0
#private sub network
iface vmbr0 inet static
        bridge_ports none
        bridge_stp off
        bridge_fd 0

        post-up echo 1 > /proc/sys/net/ipv4/ip_forward
        post-up   iptables -t nat -A POSTROUTING -s '' -o eno1 -j MASQUERADE
        post-down iptables -t nat -D POSTROUTING -s '' -o eno1 -j MASQUERADE

ZFS enabled when in installation.

70. proxmox inner network

Connecting inner network via:

post-up iptables -t nat -A POSTROUTING -s -o enp2s0f0 -j SNAT

In every nodes:

$ route add -net gw