Category: Ubuntu – ServerOK

Linux KVM Bridge network on Ubuntu

September 17, 2019

by ServerOk with No Comment Ubuntu

On Ubuntu 18.04 server, first i get Ubuntu to use /etc/network/interface, by default Ubuntu 18.04 and newer use netplan.

First install ifdown

apt install ifupdown -y

1	apt install ifupdown -y

Now you can configure your network interface by editing file

vi  /etc/network/interface

1	vi /etc/network/interface

Here is my network configuration on an OVH server.

root@ns3048991:~# cat /etc/network/interfaces
# interfaces(5) file used by ifup(8) and ifdown(8)
# Include files from /etc/network/interfaces.d:
source-directory /etc/network/interfaces.d

auto eno3
iface eno3 inet static
    address 149.202.199.137
    netmask 255.255.255.255
    broadcast 149.202.199.137
    gateway 149.202.199.254
    dns-nameservers 8.8.8.8 8.8.4.4
root@ns3048991:~#

root@ns3048991:~# cat /etc/network/interfaces

# interfaces(5) file used by ifup(8) and ifdown(8)

# Include files from /etc/network/interfaces.d:

source-directory /etc/network/interfaces.d

auto eno3

iface eno3 inet static

address 149.202.199.137

netmask 255.255.255.255

broadcast 149.202.199.137

gateway 149.202.199.254

dns-nameservers 8.8.8.8 8.8.4.4

root@ns3048991:~#

To convert this interface to bridge network, do the following

1) Replace all occurance of “eno3” with “br0”

2) Add following lines

    bridge_ports eno3
    bridge_stp off
    bridge_maxwait 5

bridge_ports eno3

bridge_stp off

bridge_maxwait 5

In above, replace “eno3” with name of your physical interface.

Here is my final network configuration.

root@ns3048991:~# cat /etc/network/interfaces
# interfaces(5) file used by ifup(8) and ifdown(8)
# Include files from /etc/network/interfaces.d:
source-directory /etc/network/interfaces.d

auto br0
iface br0 inet static
    address 149.202.199.137
    netmask 255.255.255.255
    broadcast 149.202.199.137
    gateway 149.202.199.254
    bridge_ports eno3
    bridge_stp off
    bridge_maxwait 5
    dns-nameservers 8.8.8.8 8.8.4.4
root@ns3048991:~#

root@ns3048991:~# cat /etc/network/interfaces

# interfaces(5) file used by ifup(8) and ifdown(8)

# Include files from /etc/network/interfaces.d:

source-directory /etc/network/interfaces.d

auto br0

iface br0 inet static

address 149.202.199.137

netmask 255.255.255.255

broadcast 149.202.199.137

gateway 149.202.199.254

bridge_ports eno3

bridge_stp off

bridge_maxwait 5

dns-nameservers 8.8.8.8 8.8.4.4

root@ns3048991:~#

See Linux KVM, Networking @ linux-kvm.org

Install Xfce VNC remote desktop on Ubuntu

September 17, 2019

by ServerOk with No Comment Ubuntu

XFCE is a light weight desktop for Linux. XFCE + vnc allow you to setup remote desktop on a VPS or dedicated server located on a data center or cloud. You can connect to remote desktop using VNC client and work like it is local computer.

To instal XFCE run

apt install -y xfce4 xfce4-goodies

1	apt install -y xfce4 xfce4-goodies

Next install vncserver

apt install -y vnc4server

1	apt install -y vnc4server

It is bad idea to use root user for logging into desktop. Create a normal user to run desktop.

useradd -m -s /bin/bash USERNAME_HERE

1	useradd -m -s /bin/bash USERNAME_HERE

It will be good to make this user an admin, so user can install software or update system.

usermod -aG sudo USERNAME_HERE

1	usermod -aG sudo USERNAME_HERE

Now login as the user

su - USERNAME_HERE

1	su - USERNAME_HERE

Create a vnc password for this user.

vncpasswd

vncpasswd

Create vnc startup file

vi ~/.vnc/xstartup

1	vi ~/.vnc/xstartup

Add

#!/bin/bash

xrdb $HOME/.Xresources

/usr/bin/vncconfig -nowin -display :1 &

startxfce4 &

#!/bin/bash

xrdb $HOME/.Xresources

/usr/bin/vncconfig -nowin -display :1 &

startxfce4 &

Make it executable

chmod 755 ~/.vnc/xstartup

1	chmod 755 ~/.vnc/xstartup

Now exit the user with “exit” command. You should be user “root” now.

Create service file

To auto start vncserver on boot, you need to create a service file.

vi  /etc/systemd/system/vncserver@.service

1	vi /etc/systemd/system/vncserver@.service

Add

[Unit]
Description=VNC server startup script
After=syslog.target network.target

[Service]
Type=forking
User=USERNAME_HERE
ExecStartPre=-/usr/bin/vncserver -kill :%i &> /dev/null
ExecStart=/usr/bin/vncserver -depth 24 -geometry 1920x1080 :%i
PIDFile=/home/USERNAME_HERE/.vnc/%H:%i.pid
ExecStop=/usr/bin/vncserver -kill :%i

[Install]
WantedBy=multi-user.target

[Unit]

Description=VNC server startup script

After=syslog.target network.target

[Service]

Type=forking

User=USERNAME_HERE

ExecStartPre=-/usr/bin/vncserver -kill :%i &> /dev/null

ExecStart=/usr/bin/vncserver -depth 24 -geometry 1920x1080 :%i

PIDFile=/home/USERNAME_HERE/.vnc/%H:%i.pid

ExecStop=/usr/bin/vncserver -kill :%i

[Install]

WantedBy=multi-user.target

Enable the service with

systemctl enable vncserver@1

1	systemctl enable vncserver@1

You can start/stop vncserver with

systemctl stop vncserver@1
systemctl start vncserver@1

1 2	systemctl stop vncserver@1 systemctl start vncserver@1

Now reboot the server. You should be able to connect to VNC server using SERVER_IP:1

Install HandBrake on Ubuntu 18.04

September 17, 2019

by ServerOk with No Comment Ubuntu

HandBreak is an OpenSource Video transcoder available from https://handbrake.fr. It can convert video to various format.

Latest version of Handbreak available in Ubuntu PPA. To install, enable Handbreak PPA

add-apt-repository ppa:stebbins/handbrake-releases

1	add-apt-repository ppa:stebbins/handbrake-releases

Install handbreak with

apt install handbrake-gtk handbrake-cli

1	apt install handbrake-gtk handbrake-cli

Install Linux KVM on Ubuntu

September 17, 2019

by ServerOk with No Comment Ubuntu

Linux KVM is virtualisation software that allow you to create virtual machine under linux. To install on Ubuntu, run

apt install -y qemu-kvm

1	apt install -y qemu-kvm

Install libvirtd, this allow you to easily create KVM virtual machines and allow remote connection from virt-manager GUI application.

apt install -y libvirt-bin

1	apt install -y libvirt-bin

Enable and start libvirt

systemctl enable libvirtd
systemctl start libvirtd

1 2	systemctl enable libvirtd systemctl start libvirtd

At this stage, you should be able to connect to KVM server form your computer using virt-manager.

You need to create a bridge network interface (“br0”), for this, follow instructions at Linux KVM Bridge network on Ubuntu.

Downloading ISO

Before you can setup any VM, you need to download ISO image for the OS. Here i downloaded ISO image for Ubuntu 19.04

cd /var/lib/libvirt/images
wget http://mirrors.piconets.webwerks.in/ubuntu-mirror/ubuntu-releases/19.04/ubuntu-19.04-live-server-amd64.iso

1 2	cd /var/lib/libvirt/images wget http://mirrors.piconets.webwerks.in/ubuntu-mirror/ubuntu-releases/19.04/ubuntu-19.04-live-server-amd64.iso

Once downloaded, you should be able to select this ISO image in virt-manager when creating a VM.

See Linux KVM

Set default editor in Ubuntu

September 13, 2019

by ServerOk with No Comment Ubuntu

To set default editor in Ubuntu/Debian, run

update-alternatives --config editor

1	update-alternatives --config editor

Ubuntu default editor

See update-alternatives

Install drivers on Ubuntu

August 31, 2019

by ServerOk with No Comment Ubuntu

To install drivers on Ubuntu using command line, run

boby@sok-01:~$ sudo ubuntu-drivers devices
== /sys/devices/pci0000:00/0000:00:01.1/0000:01:00.0 ==
modalias : pci:v000010DEd00001F82sv00001458sd00003FCBbc03sc00i00
vendor   : NVIDIA Corporation
driver   : nvidia-driver-430 - distro non-free recommended
driver   : xserver-xorg-video-nouveau - distro free builtin

boby@sok-01:~$

boby@sok-01:~$ sudo ubuntu-drivers devices

== /sys/devices/pci0000:00/0000:00:01.1/0000:01:00.0 ==

modalias : pci:v000010DEd00001F82sv00001458sd00003FCBbc03sc00i00

vendor : NVIDIA Corporation

driver : nvidia-driver-430 - distro non-free recommended

driver : xserver-xorg-video-nouveau - distro free builtin

boby@sok-01:~$

This list all drivers available for your hardware. You can install a driver with apt. In this cuase, i have 2 drivers available

driver   : nvidia-driver-430 - distro non-free recommended
driver   : xserver-xorg-video-nouveau - distro free builtin

1 2	driver : nvidia-driver-430 - distro non-free recommended driver : xserver-xorg-video-nouveau - distro free builtin

First driver is recommended by Ubuntu. To install, run

apt install nvidia-driver-430

1	apt install nvidia-driver-430

Install Driver using Software & Updates

Start software and updates application.

Click on Additional Drivers tab. You will see available drivers for your computer.

install ShadowSocks client in Ubuntu 18.04

August 26, 2019

by ServerOk with No Comment Ubuntu

ShadowSocks client is part of shadowsocks package. This include both client and server. If you are looking to install server, see Install ShadowSocks server on Debian 10

To install ShadowSocks, run

apt install -y shadowsocks

1	apt install -y shadowsocks

ShadowSocks client is called sslocal, get installed in /usr/bin/sslocal.

On Ubuntu, no start up script provided with this package, so you need to create one or manually run sslocal when required.

Create a service file

vi /lib/systemd/system/shadowsocks-local@.service

1	vi /lib/systemd/system/shadowsocks-local@.service

Add following content

[Unit]
Description=Shadowsocks client mode service
Documentation=man:sslocal(1)
After=network-online.target

[Service]
Type=simple
User=nobody
Group=nogroup
ExecStart=/usr/bin/sslocal -q -c /etc/shadowsocks/%i.json
Restart=on-failure
RestartSec=30

[Install]
WantedBy=multi-user.target

[Unit]

Description=Shadowsocks client mode service

Documentation=man:sslocal(1)

After=network-online.target

[Service]

Type=simple

User=nobody

Group=nogroup

ExecStart=/usr/bin/sslocal -q -c /etc/shadowsocks/%i.json

Restart=on-failure

RestartSec=30

[Install]

WantedBy=multi-user.target

Now we need to create a configuration file with your ShadowSocks server IP and password.

mkdir /etc/shadowsocks/
vi /etc/shadowsocks/local.json

1 2	mkdir /etc/shadowsocks/ vi /etc/shadowsocks/local.json

Add following content

{
    "server":"YOUR_SERVER_IP",
    "server_port":8044,
    "local_address": "127.0.0.1",
    "local_port":8044,
    "password":"PASSWORD",
    "timeout":300,
    "method":"aes-256-cfb",
    "fast_open": false,
    "workers": 1,
    "prefer_ipv6": false
}

{

"server":"YOUR_SERVER_IP",

"server_port":8044,

"local_address": "127.0.0.1",

"local_port":8044,

"password":"PASSWORD",

"timeout":300,

"method":"aes-256-cfb",

"fast_open": false,

"workers": 1,

"prefer_ipv6": false

}

“server” = IP of the server where you installled ShadowSocks server.
“server_port” = Port used by ShadowSocks server
“password” = ShadowSocks server password.

local_port can be anything you like.

Enable shadowsocks service

systemctl enable shadowsocks-local@local

1	systemctl enable shadowsocks-local@local

To start

systemctl start shadowsocks-local@local

1	systemctl start shadowsocks-local@local

To see status

systemctl status shadowsocks-local@local

1	systemctl status shadowsocks-local@local

Now you can configure your browser or other sock proxy supported application using 127.0.0.1:8044. Here is how to configure firefox

Setting up MineCraft Server in Ubuntu

August 20, 2019

by ServerOk with No Comment Ubuntu

To setup MineCraft server on Ubuntu, first you need to install Java.

apt install openjdk-8-jre -y

1	apt install openjdk-8-jre -y

Create a user to run minecraft

useradd -m --shell /bin/bash minecraft

1	useradd -m --shell /bin/bash minecraft

You can set a password if you want direct SSH login to this user or login as root, then “su – minecraft”.

passwd minecraft

1	passwd minecraft

Download minecraft server .jar file from

https://www.minecraft.net/en-us/download/server/

At the time of writing, i downloaded

wget https://launcher.mojang.com/v1/objects/3dc3d84a581f14691199cf6831b71ed1296a9fdf/server.jar

1	wget https://launcher.mojang.com/v1/objects/3dc3d84a581f14691199cf6831b71ed1296a9fdf/server.jar

Don’t use above link as it can get older, always go to minecraft site and get new link, so you get latest minecraft server jar file.

You can start minecraft server with command

java -Xmx1024M -Xms1024M -jar server.jar nogui

1	java -Xmx1024M -Xms1024M -jar server.jar nogui

First time when you run, it exit with some error related to EULA.

You need to edit file

vi eula.txt

1	vi eula.txt

Set

eula=true

eula=true

Now minecraft will run. You can create a run.sh file with following command for starting minecrat easily.

vi ~/start.sh

1	vi ~/start.sh

Paste following content

#!/bin/bash

java -Xmx1024M -Xms1024M -jar server.jar nogui

#!/bin/bash

java -Xmx1024M -Xms1024M -jar server.jar nogui

To make the file executable, chmod it 755

chmod 755 ~/start.sh

1	chmod 755 ~/start.sh

When you start minecraft from terminal/ssh, it get closed when you disconnect. To keep minecraft server running after you disconnect, use tmux or screen.

networking

August 18, 2019

by ServerOk with No Comment Ubuntu

On Ubuntu 19.04, networking service is provided by package ifupdown

apt install -y ifupdown

1	apt install -y ifupdown

By default this package is not installed. So if you add network interface configuration in /etc/network/interfaces, it won’t work.

Ubuntu 18.04 + use netplan instead of ifupdown/networking service to configure network interfaces.

Linux KVM Bridge network on Ubuntu

Configure OVH Bridge Network from command line

Ubuntu Configure systemd-resolved

August 18, 2019

by ServerOk with No Comment Ubuntu

Latest Ubuntu/Debian use systemd-resolved for DNS resolution. On a fresh Ubuntu 19.04 install DNS failed to resolve.

root@ubuntu19:/# ping serverok.in
ping: serverok.in: Temporary failure in name resolution
root@ubuntu19:/#

root@ubuntu19:/# ping serverok.in

ping: serverok.in: Temporary failure in name resolution

root@ubuntu19:/#

To fix this, create file

mkdir /etc/systemd/resolved.conf.d/
vi /etc/systemd/resolved.conf.d/dns_servers.conf

1 2	mkdir /etc/systemd/resolved.conf.d/ vi /etc/systemd/resolved.conf.d/dns_servers.conf

Add content

[Resolve]
DNS=8.8.8.8 1.1.1.1

1 2	[Resolve] DNS=8.8.8.8 1.1.1.1

Restart systemd-resolved

systemctl restart systemd-resolved

1	systemctl restart systemd-resolved

You can find systemd-resolvd status with command

resolvectl status
systemd-resolve --status

1 2	resolvectl status systemd-resolve --status

To resolve a domain, use

resolvectl query serverok.in

1	resolvectl query serverok.in