Linux Proxy Servers

Linux Proxy Servers Guide

Complete beginner-friendly guide to proxy servers on Linux, covering Arch Linux, CachyOS, and other distributions including Squid, and proxy server configuration.

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Table of Contents

1. Squid Setup
2. Proxy Configuration
3. Client Configuration
4. Troubleshooting

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Squid Setup

Install Squid

Install Squid:

# Arch/CachyOS
sudo pacman -S squid

# Debian/Ubuntu
sudo apt install squid

# Fedora
sudo dnf install squid

Configure Squid

Edit config:

# Edit config
sudo vim /etc/squid/squid.conf

Basic settings:

# HTTP port
http_port 3128

# Allow local network
acl localnet src 192.168.0.0/16
http_access allow localnet

# Deny all others
http_access deny all

Enable Service

Start Squid:

# Enable service
sudo systemctl enable squid

# Start service
sudo systemctl start squid

# Check status
systemctl status squid

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Proxy Configuration

Access Control

Configure ACLs:

# Edit config
sudo vim /etc/squid/squid.conf

Add ACLs:

# Define networks
acl localnet src 192.168.0.0/16
acl worknet src 10.0.0.0/8

# Allow access
http_access allow localnet
http_access allow worknet
http_access deny all

Caching

Configure cache:

# Edit config
sudo vim /etc/squid/squid.conf

Cache settings:

# Cache directory
cache_dir ufs /var/cache/squid 100 16 256

# Cache size (MB)
cache_mem 256 MB

# Maximum object size
maximum_object_size 10 MB

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Client Configuration

Browser Configuration

Configure browser:

1. Open browser settings
2. Network settings → Proxy
3. Manual proxy configuration
4. Enter: Proxy IP and port (3128)

System-Wide Proxy

Using environment variables:

# Set proxy
export http_proxy=http://proxy-server:3128
export https_proxy=http://proxy-server:3128
export no_proxy=localhost,127.0.0.1

# Make permanent
echo 'export http_proxy=http://proxy-server:3128' >> ~/.bashrc

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Troubleshooting

Proxy Not Working

Check logs:

# Check Squid logs
sudo journalctl -u squid

# Check access logs
sudo tail -f /var/log/squid/access.log

# Check cache logs
sudo tail -f /var/log/squid/cache.log

Test Proxy

Test connection:

# Test proxy
curl -x http://localhost:3128 http://example.com

# Test with environment
http_proxy=http://localhost:3128 curl http://example.com

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Summary

This guide covered proxy servers for Arch Linux, CachyOS, and other distributions, including Squid setup, configuration, and troubleshooting.

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Next Steps

• Networking - Network setup
• Web Servers - Web servers
• ArchWiki Proxy: https://wiki.archlinux.org/title/Proxy_server

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This guide covers Arch Linux, CachyOS, and other Linux distributions. For distribution-specific details, refer to your distribution's documentation.