commands.md

Change mode

chmod +x upgrade_ubuntu.sh

First do a dist-upgrade

sudo ./upgrade_ubuntu.sh --dist-upgrade

Then reboot

sudo reboot

Then do the release upgrade after reboot

sudo ./upgrade_ubuntu.sh --release-upgrade

To see the logs:

cat /var/log/dist-upgrade/main.log cat /var/log/dist-upgrade/apt.log

upgrade_ubuntu.sh

#!/bin/bash
# =============================================================================
# Azure Ubuntu VM Upgrade Script
# Purpose: Update packages or upgrade the OS release on an Azure Ubuntu VM.
# Usage:
#   sudo bash azure_ubuntu_upgrade.sh [--release-upgrade [22.04|24.04]] [--dist-upgrade]
#   Without options, performs a safe apt upgrade only.
# =============================================================================

set -euo pipefail

# Configuration
AZURE_AGENT_PKG="walinuxagent"
CLOUD_INIT_PKG="cloud-init"
UPDATE_MANAGER_PKG="update-manager-core"

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m'

# -----------------------------------------------------------------------------
# Helper functions
# -----------------------------------------------------------------------------
log_info()  { echo -e "${GREEN}[INFO]${NC} $*"; }
log_warn()  { echo -e "${YELLOW}[WARN]${NC} $*"; }
log_error() { echo -e "${RED}[ERROR]${NC} $*" >&2; exit 1; }

check_root() {
    if [[ $EUID -ne 0 ]]; then
        log_error "This script must be run as root (use sudo)."
    fi
}

is_azure_vm() {
    # Check if running on Azure by looking for the Azure agent
    systemctl is-active --quiet walinuxagent 2>/dev/null || dpkg -l walinuxagent &>/dev/null
}

# -----------------------------------------------------------------------------
# Package update (safe)
# -----------------------------------------------------------------------------
perform_package_update() {
    log_info "Updating package lists..."
    apt update -y

    log_info "Upgrading all packages..."
    apt upgrade -y

    # Upgrade Azure-specific packages explicitly
    if is_azure_vm; then
        log_info "Azure VM detected – ensuring Azure agent and cloud‑init are up to date..."
        apt install --only-upgrade -y "$AZURE_AGENT_PKG" "$CLOUD_INIT_PKG" || true
    fi

    # Optionally clean up
    apt autoremove -y
    apt autoclean
    log_info "Package update completed."
}

# -----------------------------------------------------------------------------
# Distribution upgrade (apt dist-upgrade)
# -----------------------------------------------------------------------------
perform_dist_upgrade() {
    log_info "Performing full distribution upgrade (apt dist-upgrade)..."
    apt update -y
    apt dist-upgrade -y
    apt autoremove -y
    apt autoclean
    log_info "Distribution upgrade completed. Please reboot if kernel was updated."
}

# -----------------------------------------------------------------------------
# OS release upgrade (e.g., 20.04 to 22.04)
# -----------------------------------------------------------------------------
perform_release_upgrade() {
    # Install update-manager-core if missing
    if ! dpkg -l "$UPDATE_MANAGER_PKG" &>/dev/null; then
        log_info "Installing $UPDATE_MANAGER_PKG..."
        apt install -y "$UPDATE_MANAGER_PKG"
    fi

    log_info "Ensuring current system is fully updated before release upgrade..."
    perform_package_update

    log_info "Upgrading to the next available LTS release (non‑interactive)..."
    export DEBIAN_FRONTEND=noninteractive
    echo "libc6 libraries/restart-without-asking boolean true" | debconf-set-selections

    # Use -d to allow upgrade before the first point release
    do-release-upgrade -f DistUpgradeViewNonInteractive --allow-third-party -m server

    log_warn "Release upgrade completed. A system reboot is strongly recommended."
}

# -----------------------------------------------------------------------------
# Main script
# -----------------------------------------------------------------------------
check_root

RELEASE_UPGRADE=false
TARGET_VERSION=""
DIST_UPGRADE=false

# Parse arguments
while [[ $# -gt 0 ]]; do
    case "$1" in
        --release-upgrade)
            RELEASE_UPGRADE=true
            if [[ -n "${2:-}" && "$2" != --* ]]; then
                TARGET_VERSION="$2"
                shift
            fi
            ;;
        --dist-upgrade)
            DIST_UPGRADE=true
            ;;
        *)
            log_error "Unknown option: $1"
            ;;
    esac
    shift
done

# Pre‑flight check: is this an Azure VM?
if is_azure_vm; then
    log_info "Running on an Azure VM."
else
    log_warn "Azure agent not detected – proceeding, but Azure‑specific steps may be skipped."
fi

# Execute requested operations
if $RELEASE_UPGRADE; then
    log_warn "======================================================================"
    log_warn "  WARNING: You are about to perform a major OS release upgrade."
    log_warn "  Ensure you have a recent snapshot/backup of the VM's OS disk."
    log_warn "======================================================================"
    read -rp "Type 'yes' to continue: " confirm
    if [[ "$confirm" != "yes" ]]; then
        log_info "Aborted by user."
        exit 0
    fi
    perform_release_upgrade "$TARGET_VERSION"
elif $DIST_UPGRADE; then
    perform_dist_upgrade
else
    perform_package_update
fi

log_info "Script completed successfully."