initialize.sh

#!/bin/bash

# Note: This script should run by root user himself, or with sudo permission.
# This is only used for setting up server at the very beginning.

# ==============================================================================
# PRESET VARIABLES
# ==============================================================================

web_base="http://172.18.99.44:8000"
ansible_public_key="ssh-rsa" 
default_dns="8.8.8.8 8.8.4.4"
default_domain=yyang.me
default_workgroup=yyang
vmwaretools_filename="VMwareTools-9.4.5-1618308.tar.gz"

# ==============================================================================
# FUNCTIONS
# ==============================================================================

# arguments: description, default value
# example: confirm_variable "IP address" $current_ip
confirm_variable()
{
  while true; do
    read -p "Please specify your $1 [$2]: " return_confirmed
    if [[ -z $return_confirmed ]]; then
      return_confirmed=$2
    fi
    if [[ ! -z $return_confirmed ]]; then
      break
    fi
    echo "Please specify a non-empty falue for $1."
  done
}

# arguments: case, string (0 for lowercase, 1 for uppercase)
# example: convert_case 0 $string
convert_case()
{
  if [ $1 = 1 ] || [ $1 = "lo" ]; then
    echo $(echo $2 | tr '[A-Z]' '[a-z]')
  else
    echo $(echo $2 | tr '[a-z]' '[A-Z]')
  fi
}

# arguments: log_string
# example: note "Success!"
note()
{
  echo $1 >> /root/server_setup.log
}

# arguments: log_string
# example: log "Success!"
log()
{
  echo "[$(date +"%r")]: $1" >> /root/server_setup.log
}

# arguments: log_string
# example: echolog "Success!"
echolog()
{
  log $1
  echo $1
}


# ---------------------------------------------------------
# STEP 0:
# Understand OS and configuration

echo "Welcome to Steve's VM Setup Script."
echo "We are detecting your operating system."

note
note "Server Setup Initiated."
note "Time: $(date), [$(date +%s)]"

# detects OS information
. /etc/os-release

os_distro=$ID
os_distro_like=$ID_LIKE
os_version=$VERSION_ID
os_arch=$(uname -m | sed 's/x86_//;s/i[3-6]86/32/')
os_pretty_name=$PRETTY_NAME
os_supported=0

log "Operating System: $os_pretty_name"
log "Linux Distro:     $os_distro, like $os_distro_like"
log "Linux Version:    $os_version, $os_arch"

case $os_distro in
  amzn ) ;;
  centos ) 
    case $os_version in
      [1-5] ) echolog "We strongly recommend to upgrade the OS.";;
      6 ) os_supported=1;;
      7 ) os_supported=1;;
      * ) echolog "Unrecognized CentOS version.";;
    esac
    ;;
  ubuntu )
    case $os_version in
      12.04 ) os_supported=1;;
      14.04 ) os_supported=1;;
      * ) echolog "We only support the LTS versions.";;
    esac
    ;;
  rhel ) ;;
  debian ) ;;
  fedora ) ;;
  * ) ;;
esac

if [[ $os_supported = 1 ]]; then
  log "OS Supported:     Yes"
  echo "Your $os_pretty_name is supported. Welcome."
  echo
else
  log "OS Supported:     No"
  echolog "Terminated due to unsupported OS, please contact git@iyyang.com for futher support."
  exit
fi

while true; do
  read -p "This script requires hard interfaces, e.g. keyboard or VM console, to further modify network settings. Are you using hard interfaces? " hardinterface_yn
  echo Your input: $hardinterface_yn
  case $hardinterface_yn in
    [Yy]* ) log "Hard Interface:   Yes"; break;;
    [Nn]* ) echolog "Terminated due to using SSH connection."; exit;;
    * ) echo "Please answer Yes or No.";;
  esac
done

net_conn_name=$default_workgroup
net_dns4=$default_dns
net_network_device=
net_ip4=
net_netmask4=
net_gw4=
net_workgroup=$default_workgroup
net_feature=server
net_domain=$default_domain
net_hostname=
net_confirmed=False

if [[ $os_distro = 'centos' ]] && [[ $os_version = 7 ]]; then
  # special implementation for CentOS 7 since it doesn't have net-tools
  net_network_device=$(nmcli dev status | grep ethernet | awk '{ print $1}')  
  net_ip4=$(ip addr | grep $net_network_device | awk '$1 == "inet" {gsub(/\/.*$/, "", $2); print $2}')
else
  IFS=$'\r\n' GLOBIGNORE='*' :
  net_network_device=($(ifconfig | grep eth | awk '{ print $1}'))
  net_ip4=$(ifconfig $net_network_device | grep 'inet addr' | cut -d: -f2 | awk '{print $1}');
fi

if [ -z $net_network_device ]; then
  echolog "Ethernet device not found. Please check your system and run the script again."
  echolog "Terminated due to ethernet device not found."
  exit
fi

while true; do
  # net_ip4
  echo
  rx='([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])'
  while true; do
    confirm_variable "IP address" $net_ip4
    target_ip4=$return_confirmed

    if [[ $target_ip4 =~ ^$rx\.$rx\.$rx\.$rx$ ]]; then
      net_ip4=$target_ip4
      break
    else
      echo "Please enter a valid IP address."
    fi
  done

  # net_netmask4
  net_netmask4="255.255.255.0"

  # net_gw4
  echo
  net_gw4=$(echo $net_ip4 | sed -r 's/([0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)([0-9]{1,3})/\1254/')
  while true; do
    confirm_variable "Gateway" $net_gw4
    target_gw4=$return_confirmed

    if [[ $target_gw4 =~ ^$rx\.$rx\.$rx\.$rx$ ]]; then
      net_gw4=$target_gw4
      break
    else
      echo "Please enter a valid IP address."
    fi
  done

  # net_workgroup
  echo
  confirm_variable "Workgroup" $net_workgroup
  net_workgroup=$return_confirmed

  # net_feature
  echo
  confirm_variable "feature of the machine" $net_feature
  net_feature=$return_confirmed

  # net_hostname
  echo
  net_hostname=$(convert_case lo $net_workgroup)-$(convert_case lo $net_feature)
  net_hostname=$net_hostname-$(echo $net_ip4 | sed -r 's/(\.)/-/g').$net_domain

  # network configuration list
  echo
  echo "Your network configuration is listed below:"
  echo "Ethernet Device:  $net_network_device"
  echo "IP Address:       $net_ip4"
  echo "Netmask:          $net_netmask4"
  echo "Gateway:          $net_gw4"
  echo "DNS:              $net_dns4"
  echo "Workgroup:        $net_workgroup"
  echo "Feature:          $net_feature"
  echo "Domain:           $net_domain"
  echo "Hostmane (generated): $net_hostname"

  # confirm information
  net_options[0]="Yes, please set up my network connection."
  net_options[1]="No, I will need to revise."
  echo "Are those information correct?"
  select net_selection in "${net_options[@]}" "Quit setup." ; do
    case "$REPLY" in
      1 ) break 2;;
      2 ) break;;
      3 ) echo "Goodbye!"; log "User Terminated"; exit;;
      * ) echo "Invalid option. Try another one."; continue;;
    esac
  done
done

log "[Network Configuration]"
log "Ethernet Device:  $net_network_device"
log "IP Address:       $net_ip4"
log "Netmask:          $net_netmask4"
log "Gateway:          $net_gw4"
log "DNS:              $net_dns4"
log "Workgroup:        $net_workgroup"
log "Feature:          $net_feature"
log "Domain:           $net_domain"
log "Hostmane (generated): $net_hostname"

echo
echo "We would want to gather more information before continue installation"

read -p "Do you wish to install 163.com repo for yum? (Yes/No) [NO] " repo_yn
if [[ $os_distro = 'rhel' ]] || [[ $os_distro = 'amzn' ]]; then
  repo_yn="Not supported"
  echo "Your distribution doesn't support foreign repo."
elif [[ $repo_yn = [Yy]* ]]; then
  repo_yn="Yes"
else
  repo_yn="No"
fi

read -p "Do you wish to upgrade your system packages? (Yes/No) [YES] " upgrade_yn
if [[ $upgrade_yn = [Nn]* ]]; then
  upgrade_yn="No"
else
  upgrade_yn="Yes"
fi

read -p "Do you wish to install ansible management user? (Yes/No) [YES] " ansible_yn
if [[ $ansible_yn = [Nn]* ]]; then
  ansible_yn="No"
else
  ansible_yn="Yes"
fi

read -p "Do you wish to install VMWare Tools? (Yes/No) [YES] " vmwaretools_yn
if [[ $vmwaretools_yn = [Nn]* ]]; then
  vmwaretools_yn="No"
else
  vmwaretools_yn="Yes"
fi

log "[System Settings]"
log "163.com mirror:   $repo_yn"
log "Upgrade packages: $upgrade_yn"
log "Ansible user:     $ansible_yn"
log "VMWare Tools:     $vmwaretools_yn"

log "[Server Setup Started ...]"

# ---------------------------------------------------------
# STEP 1:
# Set up IP address and hostname

# This part of script supports the following operating system:
# CentOS 6, 7;

# set up IP iddress
if [[ $os_distro = 'centos' ]]; then
  if [[ $os_version = 7 ]]; then
    # Note: CentOS 7 no longer has network service
    nmcli con add type ethernet con-name $net_conn_name ifname $net_network_device ip4 $net_ip4/24 gw4 $net_gw4
  elif [[ $os_version = 6 ]]; then
    eth_config_file=/etc/sysconfig/network-scripts/ifcfg-$net_network_device
    # replace if existing
    sed -i.bak -r -e "s/^.*BOOTPROTO.*/BOOTPROTO=static/" \
                  -e "s/^.*ONBOOT.*/ONBOOT=yes/" \
                  -e "s/^.*IPADDR.*/IPADDR=$net_ip4/" \
                  -e "s/^.*NETMASK.*/NETMASK=$net_netmask4/" \
                  -e "s/^.*GATEWAY.*/GATEWAY=$net_gw4/" $eth_config_file
    # append if missing
    if ! grep -xq '^BOOTPROTO' $eth_config_file; then
      echo "BOOTPROTO=static" >> $eth_config_file
    fi
    if ! grep -xq '^ONBOOT' $eth_config_file; then
      echo "ONBOOT=yes" >> $eth_config_file
    fi
    if ! grep -xq '^IPADDR' $eth_config_file; then
      echo "IPADDR=$net_ip4" >> $eth_config_file
    fi
    if ! grep -xq '^NETMASK' $eth_config_file; then
      echo "NETMASK=$net_netmask4" >> $eth_config_file
    fi
    if ! grep -xq '^GATEWAY' $eth_config_file; then
      echo "GATEWAY=$net_gw4" >> $eth_config_file
    fi
    service network restart
  fi
elif [[ $os_distro = 'ubuntu' ]]; then
  # determine the originalethernet configuration file.
  orig_eth_config_file=
  if [[ -f "/etc/network/interfaces.d/$net_network_device.cfg" ]]; then
    orig_eth_config_file=/etc/network/interfaces.d/$net_network_device.cfg
  else
    orig_eth_config_file=/etc/network/interfaces
  fi

  # create temporary directory
  temporary_dictionary="/tmp/network_interface"
  mkdir -p $temporary_dictionary
  awk_string="/^\s*iface?/ || /^\s*mapping?/ || /^\s*auto?/ || /^\s*source?/ || /^\s*allow-?/"
  awk "$awk_string {n++}{print > $temporary_dictionary n \".interfaces\" }" orig_eth_config_file
  eth_config_file=$(find $temporary_dictionary -type f -print0 | xargs -0 grep -l "iface $net_network_device")
  
  # rewrite
  echo "iface $net_network_device inet static" > $eth_config_file
  echo "    address $net_ip4" >> $eth_config_file
  echo "    netmask $net_netmask4" >> $eth_config_file
  echo "    gateway $net_gw4" >> $eth_config_file

  # put everything back
  mv $orig_eth_config_file $orig_eth_config_file.bak
  cat $temporary_dictionary/* >> $orig_eth_config_file
  rm -r $temporary_dictionary

  # restart network service
  ifdown -a && ifup -a
fi

# set up dns
if [[ $os_distro = 'centos' ]]; then
  if [[ $os_version = 7 ]]; then
    nmcli con mod $net_conn_name ipv4.dns "$net_dns4"
  # elif [[ $os_version = 6 ]]; then
  else
    dns_config_file=/etc/resolv.conf
    sed -e 's/^nameserver/# nameserver/' dns_config_file
    IFS=';' read -ra net_dns4_list <<< "$net_dns4"
    for i in "${ADDR[@]}"; do
      echo "nameserver $i" >> dns_config_file
    done
  fi
elif [[ $os_distro = 'ubuntu' ]]; then
  if [[ $os_version = '14.04' ]]; then
    dns_config_file=/etc/resolvconf/resolv.conf.d/head
    IFS=';' read -ra net_dns4_list <<< "$net_dns4"
    for i in "${ADDR[@]}"; do
      echo "nameserver $i" >> dns_config_file
    done
    resolvconf -u
  else
    dns_config_file=/etc/resolv.conf
    sed -e 's/^nameserver/# nameserver/' /etc/resolv.conf
    IFS=';' read -ra net_dns4_list <<< "$net_dns4"
    for i in "${ADDR[@]}"; do
      echo "nameserver $i" >> /etc/resolv.conf
    done
  fi
fi

# set up hostname
if [[ $os_distro = 'centos' ]]; then
  if [[ $os_version = 7 ]]; then
    hostnamectl set-hostname $net_hostname
  elif [[ $os_version = 6 ]]; then
    sed -i.bak -r -e "s/HOSTNAME.*/HOSTNAME=$net_hostname" /etc/sysconfig/network
    if ! grep -xq '^HOSTNAME' /etc/sysconfig/network; then
      echo "HOSTNAME=$net_hostname" >> /etc/sysconfig/network
    fi
    hostname "$net_hostname"
    service network restart
  fi
elif [[ $os_distro = 'ubuntu' ]]; then
  echo "$net_hostname" > /etc/hostname
  hostname -F /etc/hostname

  sed -i.bak -r -e "s/^SET_HOSTNAME.*/#&/" /etc/default/dhcpcd
fi
echo "$net_ip4  $net_hostname" >> /etc/hosts

echolog "Successfully updated network settings..."
echo

# ---------------------------------------------------------
# STEP 2:
# Install and update necessary software packages

# This part of script supports the following operating system:
# CentOS 5, 6, 7; Fedora 15, 16, 17; RHEL (without repo); Amazon (without repo);
# Ubuntu LTS (12.04 Precise and 14.04 Trusty); Debian 6, 7

if [[ $os_distro = 'centos' ]] || [[ $os_distro = 'fedora' ]] || [[ $os_distro = 'rhel' ]] || [[ $os_distro = 'amzn' ]]; then
  pkg_manager="yum"
  dependencies="net-tools perl openssh-clients openssh-server"
  echolog "The system is using yum for package management."
elif [[ $os_distro = 'debian' ]] || [[ $os_distro = 'ubuntu' ]]; then
  pkg_manager="apt"
  dependencies="net-tools perl openssh-client openssh-server"
  echolog "The system is using apt for package management."
else
  echolog "[ERROR]: Cannot detect package manager"
fi

if [[ $pkg_manager = 'yum' ]]; then
  if [[ $repo_yn = 'Yes' ]] && [[ $os_distro = 'centos' ]]; then
    # backup original centos repo
    mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak

    # download the new repo file
    curl -o /etc/yum.repos.d/CentOS-Base.repo $web_base/repos/$os_distro-$os_version
    chmod 644 /etc/yum.repos.d/CentOS-Base.repo
  elif [[ $repo_yn = 'Yes' ]] && [[ $os_distro = 'fedora' ]]; then
    # download the repo file
    curl -o /etc/yum.repos.d/fedora-163.repo $web_base/repos/fedora-163.repo
    curl -o /etc/yum.repos.d/fedora-updates-163.repo $web_base/repos/fedora-updates-163.repo
  fi

  # clean up yum
  yum clean all
  yum makecache

  # installing upgrades
  if [[ $upgrade_yn = "Yes" ]]; then
    yum -y upgrade
  fi
  # installing dependencies
  yum -y install $yum_dependencies
elif [[ $pkg_manager = 'apt' ]]; then
  # replace 163 repo
  if [[ $repo_yn = "Yes" ]]; then
    sed -i.bak -r "s_http://[a-zA-Z0-9\.]*_http://mirrors.163.com_" /etc/apt/sources.list
  fi
  # installing upgrades
  if [[ $upgrade_yn = "Yes" ]]; then
    apt-get -y update
    apt-get -y upgrade
    apt-get clean
  fi
  # installing dependencies
  apt-get -y install $apt_dependencies
fi

echolog "Successfully updated software packages..."
echo

# ---------------------------------------------------------
# STEP 3:
# Set up ansible user and update sshd services

# This part of script supports all modern operating systems.

if [[ $ansible_yn = "Yes" ]]; then
  # add ansible user
  useradd ansible

  # ad ssh key
  mkdir -p /home/ansible/.ssh
  echo $ansible_public_key > /home/ansible/.ssh/authorized_keys

  # chown
  chown -R ansible /home/ansible

  # sudo
  sed -i.bak -r 's/(^root.*)/&\nansible\tALL=(ALL)\tNOPASSWD:ALL/' /etc/sudoers
  chmod 440 /etc/sudoers

  echolog "Successfully added ansible user..."
  echo
fi

# SSHD set up is mandatory.
sshd_config_file=/etc/ssh/sshd_config

# attempt to modify in situ first.
sed -i.bak -r -e "s/^\s*#*\s*PermitRootLogin [a-z\-]*/PermitRootLogin no/" \
              -e "0,/PermitRootLogin no/! s/PermitRootLogin no/#deleted/" \
              -e "s/^\s*#*\s*PasswordAuthentication [a-z\-]*/PasswordAuthentication no/" \
              -e "0,/PasswordAuthentication no/! s/PasswordAuthentication no/#deleted/" \
              -e "/^#deleted/ D" $sshd_config_file

# reject root login if not set
if ! grep -xq '^PermitRootLogin no' $sshd_config_file; then
  echo >> $sshd_config_file
  echo "# Reject root login" >> $sshd_config_file
  echo "PermitRootLogin no" >> $sshd_config_file
fi

# reject password authentication if not set
if ! grep -xq '^PasswordAuthentication no' $sshd_config_file; then
  echo >> $sshd_config_file
  echo "# Reject password authentication" >> $sshd_config_file
  echo "PasswordAuthentication no" >> $sshd_config_file
fi

echolog "Successfully revised SSHD permissions..."
echo

# ---------------------------------------------------------
# STEP 4:
# Install VMWare Tools.

# This part of script supports all modern operating systems, however CentOS 7 has problem with current VMWare tools.

if [[ $vmwaretools_yn = "Yes" ]]; then
  # download
  cd /root
  curl -O $web_base/packages/$vmwaretools_filename

  tar -xvzf $vmwaretools_filename

  cd vmware*
  ./vmware-install.pl

  echolog "Successfully Installed VMWare Tools..."
fi

echolog "Goodbye."
echo