ubuntu_specifics

Sources: Format Pen Drive, mirror-for-download-older-release

Software Installation steps:Software Installation steps UBUNTU

#Environment setup.: append following to /etc/bash.bashrc or /etc/profile file for system level environment variables

export variable=value or export PATH=$PATH:new_path

#Change hostname:

vim /etc/hostname

#change ip address:

vim /etc/network/interfaces

auto lo

iface lo inet loopback

auto eth0

iface eth0 inet dhcp

# The host only network interface

auto eth1

iface eth1 inet static

        address 192.168.56.6

        netmask 255.255.255.0

        broadcast 192.168.56.255

How to allow sudo user to switch into root without password prompt

Add this line in visudo.

    hadoop  ALL=(ALL:ALL) NOPASSWD: ALL

GUI on Ubuntu server 14.04

sudo apt-get install --no-install-recommends ubuntu-desktop

DESKTOP ubuntu 14

gnome-system-monitor    #launch system-monitor from console.

unity-control-center        #launch settings panel from console.

cat /proc/sys/vm/swappiness    #view the vm.swappiness Linux Kernel Parameter

sysctl -w vm.swappiness=0    #setting the vm.swappiness Linux Kernel Parameter

ll /var/cache/apt/archives  #installed packages can be viewed in 

tail -n25 /var/log/apt/history.log    #How to check apt-get usage history

Install Gnome desktop on ubuntu 14.4.

1st method to install i

    sudo apt-get install gnome-shell

    sudo apt-get install ubuntu-gnome-desktop

2nd method

    sudo add-apt-repository ppa:gnome3-team/gnome3-staging

    sudo add-apt-repository ppa:gnome3-team/gnome3

    sudo apt-get update

    sudo apt-get dist-upgrade

Stop services.

service mysql stop  #stops mysql

teamviewer --daemon stop ##stops teamviewer process

Grab screen shot of specific area on screen.

Shift + Printscreen #enables you to select any area on screen, once selected will be captured. to exit selection mode can hit esc.

#Install docker:

wget https://download.docker.com/linux/ubuntu/dists/trusty/pool/stable/amd64/docker-ce_17.06.0~ce-0~ubuntu_amd64.deb

sudo dpkg -i docker-ce_17.06.0~ce-0~ubuntu_amd64.deb

netstat -tulnp | grep 80 #lists following processes running on various port and with pid.

dnsmasq # dnsmasq provides services as a DNS cacher and a DHCP server.

ntpd # It is a complete implementation of the Network Time Protocol (NTP) version 4.

aolserver4-nsd # NSD is a complete implementation of an authoritative DNS nameserver. Upon startup, NSD will read the database specified with -f database argument and put itself into background and answers queries on port 53 or a different port specified with -p port option. The database is created if it does not exist. By default, NSD will bind to all local interfaces available. Use the -a ip-address[@port] option to specify a single particular interface address to be bound. If this option is given more than once, NSD will bind its UDP and TCP sockets to all the specified ip-addresses separately. If IPv6 is enabled when NSD is compiled an IPv6 address can also be specified.

Lost controll over brightness.

#updated file /etc/default/grub

#GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"

#Launch disk utility from terminal.

gnome-disks

Samba configuration:

sudo apt-get install samba                #This installs sambaserver

sudo smbpasswd -a <user who will access shared folder>   #This adds specified user into sambaserver

Append following to /etc/samba/smb.conf

[<SHARE FOLDER NAME>]  #Square braces are required and the text within, will be used while accessing the shared folder.

path=/home/... folder to be shared

valid users = <user who will access shared folder>

read only = no

Restart smbd service

service smbd restart

Test list of shared resources via samba

testparm

systemctl is-enabled smbd  #Check if service is enabled to start on boot.

systemctl disable smbd # Disables service to start at boot.

Identify and stop unwanted services running on different ports. using "nmap"

#nmap Lists all open port, service names on given IP. I found microsoft-ds running on port 445 with netbios-ssn on 139, postfix on 25, ssh(sshd) on 22, ftp(vsftpd) on 21, http(nginx) on 80.

nmap -PN <OWN IP> 

#To identify service name or process id use :

netstat -tulnp | grep <PORT_NUMBER>

#Stopped smdb and postfix. using :

systemctl disable <SERVICE NAME>

systemctl stop <SERVICE NAME>

#Manage applications in Launcher.

gsettings list-schemas

gsettings list-keys com.canonical.Unity.Launcher

gsettings get com.cannonical.Unity.Launcher

gsettings get com.canonical.Unity.Launcher favorites #List out all applications shown in launcher

desktop-file-validate <DESKTOP_FILE> #validates the file for any syntactical errors

desktop-file-install <DESKTOP_FILE> #installs the desktop file