SRV-LIN1-02 - Configuration Réseau Automatisée

📝 Description

Ce script configure automatiquement l'interface réseau Host-Only du serveur SRV-LIN1-02 avec une IP statique, configure la passerelle et résout les noms de domaine avec le DNS. Il met également à jour le fichier /etc/hosts avec les informations correctes du serveur.

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⚙️ Caractéristiques du script

• Renomme le serveur en SRV-LIN1-02.

• Configure l'interface réseau Host-Only avec une IP statique.

• Définit la passerelle comme.

• Met à jour le fichier resolv.conf avec le serveur DNS.

• Modifie le fichier /etc/hosts avec l'IP correcte pour SRV-LIN1-02.

• Affiche un récapitulatif de la configuration appliquée et demande confirmation avant de redémarrer le service réseau.

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🚀 Commande d'exécution rapide

Pour exécuter ce script de manière automatisée sur votre serveur Debian, utilisez la commande suivante. Cela installera curl si nécessaire, puis téléchargera et exécutera le script en une seule étape :

sudo apt-get install curl -y && sudo bash -c "$(curl -fsSL https://gitlab.com/Ruimmp/cpnv-es/-/raw/LIN1/1.%20Param%C3%A9trage%20du%20R%C3%A9seau%20et%20Services%20Syst%C3%A8mes/cpnv_lin1_srv02_network_setup.sh)"

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⚙️ Le Script en Détail

Voici le code brut du script de la configuration du réseau pour le SRV-LIN1-01. Ce script a été testé sur Debian 12.6.4.

#!/bin/bash

############################################################################################################
# Script Name   : cpnv_lin1_srv02_network_setup.sh
# Author        : Rui Monteiro ([e-mail])
# Created       : 2024-09-28
# Last Updated  : 2024-11-08
#
# Version       : 1.4
#
# Description   : This script automates the network configuration of SRV-LIN1-02, including setting up
#                 the Host-Only network interface with a static IP, configuring the gateway, and setting
#                 up DNS resolution using resolv.conf. It also renames the machine to SRV-LIN1-02.
#
# Features      : - Configures the Host-Only interface with a static IP.
#                 - Sets the gateway and DNS nameservers.
#                 - Configures resolv.conf to ensure proper DNS resolution.
#                 - Renames the machine to SRV-LIN1-02.
#
# Usage         : Run the script with sudo privileges:
#                     sudo bash -c "$(curl -fsSL https://gitlab.com/Ruimmp/cpnv-es/-/raw/LIN1/1.%20Param%C3%A9trage%20du%20R%C3%A9seau%20et%20Services%20Syst%C3%A8mes/cpnv_lin1_srv02_network_setup.sh)"
#                 The script will automatically configure the network interfaces and services.
#                 After completion, reconnect using the new IP address assigned to SRV-LIN1-02.
#
# System Tested : Debian 12.6.4
#
# Prerequisites : - Debian 12.6.4 or compatible Debian-based distribution.
#                 - Sudo privileges for system configuration.
#                 - Internet connection for package installations (if necessary).
#
# Dependencies  : This script requires the following packages:
#                 - resolvconf (For DNS resolution management, if installed).
#
# Return Values : On successful completion, the script:
#                 - Configures the Host-Only interface with the static IP.
#                 - Renames the server to SRV-LIN1-02.
#                 - Sets up DNS resolution with the correct nameservers.
#                 - Provides the system's current network configuration.
#
# Notes         : - Ensure that the network is properly configured and the DNS server is reachable.
#                 - The script modifies /etc/resolv.conf to ensure proper DNS configuration.
############################################################################################################

# Global variables
DNS_SERVER="10.10.10.11"
HOST_ONLY_INTERFACE=$(ip -o link | grep 'ens.*:' | awk -F: '{gsub(/ /,"",$2); print $2}' | grep -v 'lo' | head -n 1)

# Network configuration variables
LOCAL_DOMAIN="lin1.local"
SRV1_IP="10.10.10.11"
SRV2_IP="10.10.10.22"

# Server names
SRV2_HOSTNAME="SRV-LIN1-02"

# Function to update the system
update_system() {
  echo "Updating system packages..."
  apt-get update && apt-get upgrade -y
}

# Function to rename the machine to SRV-LIN1-02
rename_machine() {
  echo "Renaming the machine to $SRV2_HOSTNAME..."

  hostnamectl set-hostname $SRV2_HOSTNAME
  echo "$SRV2_HOSTNAME" >/etc/hostname
  echo "Machine renamed to $SRV2_HOSTNAME."
}

# Function to configure network interfaces
configure_network_interfaces() {
  echo "Configuring network interfaces..."

  cat <<EOF >/etc/network/interfaces
source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface (Host-Only)
auto $HOST_ONLY_INTERFACE
allow-hotplug $HOST_ONLY_INTERFACE
iface $HOST_ONLY_INTERFACE inet static
        address $SRV2_IP/24
        gateway $SRV1_IP
        dns-nameservers $DNS_SERVER
EOF
}

# Function to configure resolv.conf and prevent auto-updates
configure_resolv_conf() {
  echo "Configuring resolv.conf..."

  # Overwrite the resolv.conf file with the desired nameserver
  echo "domain localdomain" >/etc/resolv.conf
  echo "search localdomain" >>/etc/resolv.conf
  echo "nameserver $DNS_SERVER" >>/etc/resolv.conf

  # Prevent resolv.conf from being automatically updated
  echo "Preventing automatic updates to resolv.conf..."
  sudo sed -i '/domain-name, domain-name-servers, domain-search, host-name,/d' /etc/dhcp/dhclient.conf
}

# Function to update /etc/hosts with the static IP and FQDN for SRV2
update_local_hostname() {
  echo "Updating /etc/hosts with the correct IP and FQDN for $SRV2_HOSTNAME..."

  # Check if there is an existing entry for SRV2's IP and FQDN, and update or add it
  if grep -q "$SRV2_IP" /etc/hosts; then
    sed -i "s/$SRV2_IP.*/$SRV2_IP       $SRV2_HOSTNAME.$LOCAL_DOMAIN/g" /etc/hosts
  else
    # If not present, add the new entry
    echo "$SRV2_IP       $SRV2_HOSTNAME.$LOCAL_DOMAIN" >>/etc/hosts
  fi

  echo "/etc/hosts updated with $SRV2_IP $SRV2_HOSTNAME.$LOCAL_DOMAIN."
}

# Function to apply network configuration changes
apply_network_configuration() {
  echo "Applying network configurations..."
  echo "Reconnect using the new IP address: $SRV2_IP"
  systemctl restart networking.service
}

# Function to display final information
display_info() {
  echo "#######################################"
  echo "#         Network Setup Summary       #"
  echo "#######################################"

  # Check if the machine hostname is correctly set
  echo ""
  echo "Hostname Verification:"
  if [ "$(hostname)" = "$SRV2_HOSTNAME" ]; then
    echo "  Hostname is set to $SRV2_HOSTNAME (configured correctly)"
  else
    echo "  Error: Hostname is not set correctly"
  fi

  # Check Host-Only Interface configuration in /etc/network/interfaces
  echo ""
  echo "Host-Only Interface ($HOST_ONLY_INTERFACE):"
  if grep -q "address $SRV2_IP" /etc/network/interfaces; then
    echo "  IP Address: $SRV2_IP (configured correctly in /etc/network/interfaces)"
  else
    echo "  Error: IP Address not configured correctly in /etc/network/interfaces"
  fi

  # Check if DNS Server is correctly set in resolv.conf
  echo ""
  echo "DNS Server Configuration:"
  if grep -q "nameserver $DNS_SERVER" /etc/resolv.conf; then
    echo "  DNS Server: $DNS_SERVER (configured correctly)"
  else
    echo "  Error: DNS Server not correctly configured in /etc/resolv.conf"
  fi

  # Check if /etc/hosts was updated
  echo ""
  echo "/etc/hosts File:"
  if grep -q "$SRV2_IP" /etc/hosts; then
    echo "  /etc/hosts updated with IP $SRV2_IP and hostname $SRV2_HOSTNAME"
  else
    echo "  Error: /etc/hosts not updated correctly"
  fi

  echo ""
  echo "############################################################"
  echo "#  Summary of network configuration changes above          #"
  echo "############################################################"
}

# Function to wait for user confirmation before reconnection
wait_for_user_confirmation() {
  echo ""
  echo "#######################################"
  echo "# Press Enter to confirm the changes  #"
  echo "# Your SSH session will be terminated #"
  echo "# Reconnect using the new IP address  #"
  echo "#######################################"
  read -p ""
}

# Main function to run all configurations
main() {
  rename_machine
    update_local_hostname
  update_static_ip_hostname
  configure_network_interfaces
  configure_resolv_conf
  display_info
  wait_for_user_confirmation
  apply_network_configuration
}

# Execute the script
main

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📋 Résultats et valeurs de sortie

Après l'exécution du script, voici un exemple des résultats attendus :

#######################################
#         Network Setup Summary       #
#######################################

Hostname Verification:
  Hostname is set to SRV-LIN1-02 (configured correctly)

Host-Only Interface (ens33):
  IP Address: 10.10.10.22 (configured correctly in /etc/network/interfaces)

DNS Server Configuration:
  DNS Server: 10.10.10.11 (configured correctly)

/etc/hosts File:
  /etc/hosts updated with IP 10.10.10.22 and hostname SRV-LIN1-02

############################################################
#  Summary of network configuration changes above          #
############################################################

#######################################
# Press Enter to confirm the changes  #
# Your SSH session will be terminated #
# Reconnect using the new IP address  #
#######################################