Implementation:Microsoft Autogen Dotnet Install Script

Knowledge Sources	Microsoft_Autogen
Domains	Installation, DotNet, Shell_Scripting
Last Updated	2026-02-11 17:00 GMT

Overview

A comprehensive Bash script for downloading and installing the .NET SDK and runtime on Unix-like systems (Linux, macOS, FreeBSD).

Description

This is the official .NET installation script from Microsoft, included in the AutoGen repository for .NET development support. It provides a robust, cross-platform solution for installing specific versions of .NET SDK, .NET Runtime, or ASP.NET Core Runtime. The script handles OS detection (including special cases like Alpine Linux musl, RHEL 6), architecture detection (x64, arm, arm64, s390x, ppc64le, loongarch64, riscv64), version resolution from channels or specific version strings, download and validation of installation packages, and extraction to specified directories. It includes extensive error handling, verbose logging options, and support for quality channels (daily, preview, GA).

Usage

Use this script when you need to:

• Install .NET SDK or runtime in CI/CD pipelines
• Set up development environments without package managers
• Install specific .NET versions for compatibility
• Install .NET on systems without official package manager support
• Automate .NET installation across multiple platforms

Code Reference

Source Location

• Repository: Microsoft_Autogen
• File: dotnet/dotnet-install.sh

Signature

#!/usr/bin/env bash
# .NET SDK/Runtime Installation Script
# Copyright (c) .NET Foundation and contributors

# Core Functions:
get_current_os_name()           # Detect OS (linux/osx/freebsd/linux-musl)
get_machine_architecture()      # Detect architecture (x64/arm/arm64/etc)
get_normalized_architecture()   # Normalize architecture names
is_arm64_supported()            # Check if version supports ARM64
get_normalized_os()             # Normalize OS names
get_normalized_quality()        # Normalize quality (daily/preview/ga)
get_normalized_channel()        # Normalize channel (LTS/STS)
get_normalized_product()        # Normalize product (sdk/runtime/aspnetcore)
validate_remote_local_file_sizes() # Verify download integrity
download()                      # Download files with curl or wget
extract()                       # Extract tar.gz archives
install_dotnet()                # Main installation logic

Import

# Script uses standard Unix tools:
# - curl or wget (for downloads)
# - tar (for extraction)
# - uname (for OS/arch detection)
# - tput (for colored output)
# - ldd (for musl detection)

# Script requires bash and sets strict error handling:
set -e          # Exit on error
set -u          # Exit on undefined variable
set -o pipefail # Fail on pipe errors

I/O Contract

Inputs

Name	Type	Required	Description
--channel	string	No	Release channel (LTS, STS, or version like 8.0)
--version	string	No	Specific version or 'latest'
--quality	string	No	Build quality (daily, preview, ga)
--install-dir	path	No	Installation directory (default: $HOME/.dotnet)
--architecture	string	No	Target architecture (x64, arm, arm64, etc.)
--runtime	string	No	Runtime type (dotnet, aspnetcore) - installs runtime instead of SDK
--os	string	No	Override OS detection (osx, linux, freebsd, rhel.6, linux-musl)
--dry-run	flag	No	Display download URL without installing
--no-path	flag	No	Don't add to PATH
--verbose	flag	No	Enable verbose logging
--azure-feed	url	No	Custom Azure feed URL
--uncached-feed	url	No	Custom uncached feed URL
--feed-credential	string	No	Feed authentication token
--runtime-id	string	No	Specific runtime identifier
--skip-non-versioned-files	flag	No	Skip copying non-versioned files
--no-cdn	flag	No	Disable CDN usage
--jsonfile	path	No	Path to JSON file with installation parameters

Outputs

Name	Type	Description
Exit Code	integer	0 on success, non-zero on failure
Installed Files	directory	.NET SDK/runtime files in install directory
Console Output	text	Installation progress and status messages
Error Messages	text	Detailed error information on stderr
Environment Variables	suggestion	PATH update suggestions (if --no-path used)

Usage Examples

Install Latest SDK

# Install latest stable .NET SDK to default location (~/.dotnet):
./dotnet-install.sh

# Install to custom directory:
./dotnet-install.sh --install-dir /opt/dotnet

Install Specific Version

# Install .NET 8.0 SDK:
./dotnet-install.sh --channel 8.0

# Install exact version:
./dotnet-install.sh --version 8.0.303

# Install latest version from channel:
./dotnet-install.sh --channel 8.0 --version latest

Install Runtime Only

# Install .NET Runtime (not full SDK):
./dotnet-install.sh --runtime dotnet --channel 8.0

# Install ASP.NET Core Runtime:
./dotnet-install.sh --runtime aspnetcore --channel 8.0

Architecture-Specific Installation

# Install ARM64 SDK on Apple Silicon Mac:
./dotnet-install.sh --architecture arm64 --channel 8.0

# Install x64 SDK (for Rosetta emulation):
./dotnet-install.sh --architecture x64 --channel 8.0

Preview/Daily Builds

# Install preview builds:
./dotnet-install.sh --channel 9.0 --quality preview

# Install daily builds (latest nightly):
./dotnet-install.sh --channel 9.0 --quality daily

Dry Run Mode

# Display download URL without installing:
./dotnet-install.sh --channel 8.0 --dry-run

# Verbose dry run for debugging:
./dotnet-install.sh --channel 8.0 --dry-run --verbose

CI/CD Usage

# Typical CI installation:
curl -sSL https://dot.net/v1/dotnet-install.sh | bash /dev/stdin \
  --channel 8.0 \
  --install-dir ./dotnet \
  --no-path

# Add to PATH:
export PATH="$PWD/dotnet:$PATH"
export DOTNET_ROOT="$PWD/dotnet"

Multiple Version Installation

# Install .NET 6, 8, and 9 side by side:
./dotnet-install.sh --channel 6.0 --install-dir ~/.dotnet
./dotnet-install.sh --channel 8.0 --install-dir ~/.dotnet
./dotnet-install.sh --channel 9.0 --install-dir ~/.dotnet

# All versions coexist in ~/.dotnet

Key Functions

OS Detection

The script detects the operating system using uname and /etc/os-release:

• Darwin → osx
• Linux → linux (or linux-musl for Alpine-based distros)
• FreeBSD → freebsd
• Special handling for RHEL 6 and musl-based distributions

Architecture Detection

Detects CPU architecture and normalizes names:

• x86_64, amd64 → x64
• armv7l → arm
• aarch64, arm64 → arm64 (with 32-bit OS detection)
• s390x, ppc64le, loongarch64, riscv64 → same
• Default fallback: x64

ARM64 Compatibility

Special logic for Apple Silicon Macs:

• Checks if .NET version supports ARM64 (6.0+)
• Falls back to x64 with Rosetta emulation for older versions
• Validates Rosetta is installed before attempting x64 installation

Download Logic

Prefers curl over wget with automatic fallback:

• Validates required tools exist (check_min_reqs)
• Supports custom feeds and authentication
• Performs file size validation after download
• Retries on failure with detailed error messages

Version Resolution

Resolves versions from channels:

• Channel → Latest patch version (e.g., 8.0 → 8.0.303)
• LTS → Long-term support channel
• STS → Standard-term support channel
• latest → Most recent build from channel

Platform Support

Operating Systems

• Linux (glibc-based distributions)
• Linux (musl-based: Alpine)
• macOS (Intel and Apple Silicon)
• FreeBSD
• RHEL 6 (legacy support)

Architectures

• x64 (AMD64/Intel 64-bit)
• arm (32-bit ARM)
• arm64 (64-bit ARM/AArch64)
• s390x (IBM Z)
• ppc64le (PowerPC 64-bit Little Endian)
• loongarch64 (LoongArch)
• riscv64 (RISC-V 64-bit)

Error Handling

The script includes comprehensive error handling:

• Validates prerequisites (curl/wget)
• Checks architecture support
• Verifies download integrity
• Validates extracted files exist
• Provides colored error messages with context
• Suggests fixes for common issues

Common Errors

• curl/wget missing → Install required download tool
• Unsupported architecture → Check if .NET supports your platform
• Version not found → Verify channel and version exist
• Download failed → Check network and feed URLs
• Extraction failed → Check disk space and permissions

Related Pages

• Microsoft_Autogen_Dotnet_Build_Workflow - Uses this script in CI pipeline
• Cross_Platform_Installation - Installation best practices
• DotNet_SDK - .NET development environment
• Version_Management - Managing multiple SDK versions