Migrating Docker Services Between Servers: The Critical Nuance of Upstream Configuration

Introduction

Migrating Docker-based services from one server to another seems straightforward at first: copy the containers, move the volumes, update the DNS. However, there’s a critical detail that can trip you up if you’re using a reverse proxy like Nginx Proxy Manager, Traefik, or Caddy: where you point your upstreams matters more than you might think.

In this article, I’ll walk through a real-world migration scenario where services were consolidated from multiple servers onto a single instance, and the key lesson learned about upstream configuration. Whether you’re new to Docker networking or an experienced DevOps engineer, understanding this nuance will save you hours of troubleshooting.

Understanding the Scenario: Distributed vs. Consolidated Architecture

The Original Architecture

Many organizations start with a distributed infrastructure where services run across multiple machines:

┌─────────────────────┐         ┌─────────────────────┐
│  Server A (Public)  │         │  Server B (Private) │
│                     │         │                     │
│  ┌───────────────┐  │   VPN   │  ┌───────────────┐  │
│  │ Reverse Proxy │  │◄────────►│  │ Service 1     │  │
│  │ (Nginx/Traefik│  │         │  │ Service 2     │  │
│  │  /Caddy)      │  │         │  │ Service 3     │  │
│  └───────────────┘  │         │  └───────────────┘  │
│                     │         │                     │
│  Exposed to Internet│         │  Internal Network  │
└─────────────────────┘         └─────────────────────┘

Why this setup exists:

• Services were deployed at different times
• Different security requirements
• Resource constraints on individual servers
• Legacy infrastructure decisions

In this distributed setup, the reverse proxy (running on the public-facing server) must route traffic to services using external IP addresses and host-mapped ports, since services are on different physical machines.

The Consolidation Goal

As infrastructure matures, there’s often a desire to consolidate services onto fewer servers:

Benefits of consolidation:

• Reduced infrastructure complexity
• Lower operational overhead
• Improved network performance (services on the same host)
• Simplified maintenance and monitoring
• Better resource utilization
• Lower costs

The key insight: Once services are on the same Docker host, you no longer need to point to external IP addresses. You can leverage Docker’s internal networking and use container hostnames instead.

Architecture After Consolidation

┌─────────────────────────────────────────┐
│     Single Server (Public-Facing)      │
│                                         │
│  ┌─────────────────────────────────┐  │
│  │  Reverse Proxy                  │  │
│  │  (Exposed to Internet)           │  │
│  └─────────────────────────────────┘  │
│              │                         │
│              │ Docker Internal         │
│              │ Networking              │
│              ▼                         │
│  ┌─────────────────────────────────┐  │
│  │  Service 1 (container)           │  │
│  │  Service 2 (container)           │  │
│  │  Service 3 (container)           │  │
│  └─────────────────────────────────┘  │
│                                         │
└─────────────────────────────────────────┘

The Problem: Two Approaches to Upstream Configuration

When configuring your reverse proxy to route traffic to backend services, you have two fundamental approaches:

Option 1: Point to External IP Address and Port

Forward Hostname/IP: 192.168.1.100
Forward Port: 8080
Forward Scheme: http

When to use this approach:

• Services are on different physical machines
• Services are connected via VPN or private network
• You’re proxying to non-Docker services
• You need to route through a load balancer
• Services haven’t been consolidated yet

How it works:

• Traffic flows: Internet → Reverse Proxy → Host Network → Target Server IP → Host Port → Container
• Requires ports to be exposed on the host
• Traffic traverses the network between machines

Option 2: Point to Container Hostname and Internal Port

Forward Hostname/IP: myapp-nginx-1
Forward Port: 8080
Forward Scheme: http

When to use this approach:

• All services are on the same Docker host (after consolidation)
• You want to leverage Docker’s internal networking
• You want better network isolation
• You want to avoid port conflicts

How it works:

• Traffic flows: Internet → Reverse Proxy → Docker Network → Container Hostname → Container Port
• No need to expose ports on the host
• Traffic stays within Docker’s network namespace

The critical difference: The first approach routes traffic through the host’s network stack and across the network (VPN/external network), while the second routes directly through Docker’s internal networking on the same host. This is not just a configuration preference—it’s a fundamental architectural improvement enabled by consolidation.

Why Container Hostnames Are Better (When Possible)

1. Network Isolation and Security

When you use container hostnames, traffic stays within Docker’s network namespace:

Benefits:

• No exposed ports: Services don’t need ports exposed on the host
• Better isolation: Containers communicate through Docker’s network bridge
• Reduced attack surface: Services aren’t directly accessible from the host network
• Internal routing: Traffic doesn’t traverse the host’s network stack

Example:

# With external IP - port must be exposed
services:
  app:
    ports:
      - "8080:8080"  # Required for external access

# With container hostname - no port exposure needed
services:
  app:
    # No ports section needed!

2. Port Independence

Container hostnames use the internal container port, not the host-mapped port:

Benefits:

• Change host ports freely: You can remap host ports without breaking the proxy
• Avoid port conflicts: Multiple services can use the same host port (e.g., 8080) without conflicts
• Portable configuration: Configuration works across different environments
• Simpler setup: No need to coordinate host port assignments

Example scenario:

Service A: Container port 8080, Host port 5001
Service B: Container port 8080, Host port 5002
Service C: Container port 8080, Host port 5003

With container hostnames, all three can use port 8080 internally.
With external IPs, you'd need different host ports for each.

3. Network Resilience

Docker’s internal DNS resolution provides better reliability:

Benefits:

• Automatic service discovery: Docker handles DNS resolution automatically
• Better health checks: Health checks work more reliably within Docker networks
• Container restart resilience: Container restarts don’t break connections as easily
• Load balancing: Docker can handle multiple containers with the same service name

4. Simplified Configuration

Before (External IP):

# Must know exact IP and port
set $server "192.168.1.100";
set $port 8080;

After (Container Hostname):

# Uses Docker's internal DNS
set $server "myapp-nginx-1";
set $port 8080;

The Migration Process: Step by Step

Phase 1: Discovery and Inventory

Before migrating, thoroughly document your current setup. This step is crucial for both beginners and experts.

For beginners: This helps you understand your infrastructure before making changes.

For experts: This creates a rollback plan if something goes wrong.

# Find all running containers
docker ps --format "table {{.Names}}\t{{.Image}}\t{{.Ports}}"

# Identify networks
docker network ls

# Check which network each container is on
docker inspect <container-name> --format '{{range $k, $v := .NetworkSettings.Networks}}{{printf "%s " $k}}{{end}}'

# List all volumes
docker volume ls

# Check container environment variables
docker inspect <container-name> --format '{{range .Config.Env}}{{println .}}{{end}}'

Key Information to Document:

• Container names and their purposes
• Network names and which containers use them
• Port mappings (host:container)
• Volume mounts and their purposes
• Environment variables
• Health check configurations
• Dependencies between services

Create a migration checklist:

[ ] Service 1
    - Container: service1-app-1
    - Network: service1_default
    - Internal Port: 8080
    - Host Port: 5001
    - Volumes: service1_data
    - Dependencies: service1-db-1

[ ] Service 2
    ...

Phase 2: Set Up the Destination Server

On your destination server:

1. Install Docker and Docker Compose# Verify Docker is installed docker --version docker compose version
2. Plan your network strategy
   • Will you recreate the same network names?
   • Will you use a shared network for all services?
   • Document your network architecture
3. Prepare for volume migration
   • Ensure sufficient disk space
   • Plan backup locations
   • Consider transfer methods (scp, rsync, etc.)

Phase 3: Migrate Services

For each service, follow these steps:

Step 3.1: Export Volumes

# On source server
docker run --rm \
  -v <volume-name>:/data \
  -v $(pwd):/backup \
  alpine tar czf /backup/<volume-name>.tar.gz -C /data .

What this does: Creates a compressed backup of your Docker volume data.

Step 3.2: Transfer to Destination

# Using SCP
scp <volume-name>.tar.gz user@destination-server:~/

# Or using rsync (better for large files)
rsync -avz <volume-name>.tar.gz user@destination-server:~/

Step 3.3: Import Volumes

# On destination server
docker volume create <volume-name>
docker run --rm \
  -v <volume-name>:/data \
  -v $(pwd):/backup \
  alpine tar xzf /backup/<volume-name>.tar.gz -C /data

Step 3.4: Deploy Containers

# Copy docker-compose.yml to destination
scp docker-compose.yml user@destination-server:~/myapp/

# On destination server
cd ~/myapp
docker compose up -d

Verify deployment:

docker ps | grep myapp
docker logs myapp-app-1

Phase 4: The Critical Step – Update Reverse Proxy Configuration

This is where the nuance matters most. The approach differs slightly depending on your reverse proxy.

Step 4.1: Ensure Network Connectivity

Your reverse proxy container must be on the same network as the services it’s proxying to.

Check current networks:

# Replace 'reverse-proxy-container' with your actual container name
docker inspect reverse-proxy-container \
  --format '{{range $k, $v := .NetworkSettings.Networks}}{{printf "%s " $k}}{{end}}'

Connect to the service’s network:

docker network connect <service-network> reverse-proxy-container

Example:

# If your service is on 'myapp_default' network
docker network connect myapp_default nginx-proxy-manager

Why this is necessary: The reverse proxy needs to be on the same Docker network to resolve container hostnames via Docker’s internal DNS. Without this, the proxy can’t find your containers by name.

For beginners: Think of Docker networks like virtual LANs. Containers on the same network can talk to each other by name, but containers on different networks cannot (unless explicitly connected).

Step 4.2: Update the Proxy Configuration

You have multiple methods depending on your reverse proxy:

Method A: Via Web UI (Recommended for beginners)

If using Nginx Proxy Manager, Traefik dashboard, or similar:

1. Log into your reverse proxy’s web interface
2. Find the proxy host/route configuration
3. Update:
   • Forward Hostname/IP: Change from external IP to container hostname
   • Forward Port: Change from host-mapped port to internal container port
4. Save and test

Example (Nginx Proxy Manager):

Before:
  Forward Hostname/IP: 192.168.1.100
  Forward Port: 5001

After:
  Forward Hostname/IP: myapp-nginx-1
  Forward Port: 8080

Method B: Direct Configuration Update (For automation/experts)

For Nginx Proxy Manager:

Nginx Proxy Manager stores configuration in SQLite. You can update it programmatically:

# Find the proxy host ID first
docker exec nginx-proxy-manager python3 -c "
import sqlite3
conn = sqlite3.connect('/data/database.sqlite')
cursor = conn.cursor()
cursor.execute('SELECT id, domain_names, forward_host, forward_port FROM proxy_host')
for row in cursor.fetchall():
    print(row)
conn.close()
"

# Update the configuration
docker exec nginx-proxy-manager python3 -c "
import sqlite3
conn = sqlite3.connect('/data/database.sqlite')
cursor = conn.cursor()
cursor.execute('UPDATE proxy_host SET forward_host = ?, forward_port = ? WHERE id = ?', 
               ('myapp-nginx-1', 8080, <proxy-host-id>))
conn.commit()
print(f'Updated proxy host {<proxy-host-id>}')
conn.close()
"

# Update the generated nginx config file
docker exec nginx-proxy-manager sed -i \
  's/set \$server.*"192.168.1.100";/set $server "myapp-nginx-1";/' \
  /data/nginx/proxy_host/<id>.conf

docker exec nginx-proxy-manager sed -i \
  's/set \$port.*5001;/set $port 8080;/' \
  /data/nginx/proxy_host/<id>.conf

# Reload nginx
docker exec nginx-proxy-manager nginx -t
docker exec nginx-proxy-manager nginx -s reload

For Traefik:

Update your docker-compose.yml or Traefik configuration:

# Before (external IP)
labels:
  - "traefik.http.services.myapp.loadbalancer.server.url=http://192.168.1.100:5001"

# After (container hostname)
labels:
  - "traefik.http.services.myapp.loadbalancer.server.url=http://myapp-nginx-1:8080"

For Caddy:

Update your Caddyfile:

# Before
myapp.example.com {
    reverse_proxy 192.168.1.100:5001
}

# After
myapp.example.com {
    reverse_proxy myapp-nginx-1:8080
}

Step 4.3: Verify Connectivity

Test that your reverse proxy can reach the container:

# Check DNS resolution (from within reverse proxy container)
docker exec reverse-proxy-container getent hosts myapp-nginx-1

# Expected output:
# 172.31.0.3      myapp-nginx-1

If DNS resolution fails:

• Verify the reverse proxy is on the same network
• Check that the service container is running
• Verify the container name is correct

Test direct connectivity:

# From reverse proxy container, test HTTP connection
docker exec reverse-proxy-container wget -qO- --timeout=2 http://myapp-nginx-1:8080 || echo "Connection failed"

Phase 5: Verification and Testing

Before switching DNS or making the change live:

1. Test internal connectivity:# From the server, test direct container access curl -I http://myapp-nginx-1:8080
2. Test through proxy:# Test via reverse proxy (using internal IP or hosts file) curl -I http://<server-ip>/myapp # Or if using domain: curl -I https://myapp.example.com
3. Check logs:# Reverse proxy logs docker logs reverse-proxy-container | tail -50 # Service logs docker logs myapp-nginx-1 | tail -50
4. Monitor for errors:# Watch for connection errors docker logs -f reverse-proxy-container | grep -i error

Common Pitfalls and How to Avoid Them

Pitfall 1: Using Host IP Instead of Container Hostname

Symptom: Proxy works initially but breaks when:

• Containers restart (IPs might change)
• Port mappings change
• Network configuration changes
• Docker daemon restarts

Why it happens: Host IPs and ports are less stable than container hostnames in Docker’s dynamic environment.

Solution: Always use container hostnames for services on the same Docker host.

Example of the problem:

# Fragile - breaks if container restarts or port changes
set $server "172.17.0.5";
set $port 5001;

# Robust - uses Docker's internal DNS
set $server "myapp-nginx-1";
set $port 8080;

Pitfall 2: Using Host-Mapped Ports

Symptom: Configuration breaks when:

• Multiple services need the same port
• Port conflicts occur
• You want to change exposed ports
• You’re trying to run multiple instances

Why it happens: Host ports are a limited resource and must be unique per host.

Solution: Use internal container ports (typically 80, 8080, 3000, etc.). These can be the same across multiple containers.

Example:

❌ Bad: Multiple services trying to use host port 8080
Service A: 8080:8080
Service B: 8081:8080  # Must use different host port

✅ Good: All use same internal port, different hostnames
Service A: myapp-a-1:8080
Service B: myapp-b-1:8080

Pitfall 3: Not Connecting to the Right Network

Symptom: DNS resolution fails:

getent hosts myapp-nginx-1
# Returns nothing or "Host not found"

Why it happens: Docker networks are isolated. Containers can only resolve hostnames of containers on the same network.

Solution: Ensure your reverse proxy is on the same network as your services:

# Check networks
docker network inspect <network-name>

# Connect reverse proxy to service network
docker network connect <service-network> reverse-proxy-container

For beginners: This is like trying to call someone on a different phone network without the right connection. Docker networks are separate until you explicitly connect them.

Pitfall 4: Mixing Approaches Inconsistently

Symptom: Some services work, others don’t, with no clear pattern.

Why it happens: Inconsistent configuration makes troubleshooting difficult and creates maintenance burden.

Solution: Standardize on one approach:

• Same-host services: Always use container hostnames
• External services: Always use IP addresses or FQDNs
• Document your decision so the team knows the pattern

Create a configuration standard:

Our Standard:
- Services on same Docker host: Use container hostname + internal port
- Services on different hosts: Use IP address + host port
- External services: Use FQDN or IP address

Pitfall 5: Not Understanding Port Types

Common confusion: The difference between host ports and container ports.

Host Port: The port exposed on the Docker host (e.g., 5001:8080 means host port 5001) Container Port: The port the application listens on inside the container (e.g., 5001:8080 means container port 8080)

When using container hostnames, you use the container port:

# Container listens on 8080 internally
# Host might map it to 5001 externally
# But with container hostname, use 8080
set $port 8080;  # Container port, not host port!

Best Practices

1. Standardize Your Approach

Decide on a strategy and stick to it:

Decision matrix:

• Same-host services: Use container hostnames
• External services: Use IP addresses or FQDNs
• Document your decision so the team knows the pattern
• Create a runbook for future migrations

Example standard:

# Our Reverse Proxy Configuration Standard

## Same-Host Services (Docker)
- Use: Container hostname + internal port
- Example: `myapp-nginx-1:8080`
- Network: Must be on same Docker network

## External Services
- Use: IP address or FQDN + port
- Example: `192.168.1.100:8080` or `external-service.example.com:443`
- Network: Via host network or VPN

2. Use Named Networks

Instead of relying on default networks, use explicit named networks:

# docker-compose.yml
version: '3.8'

networks:
  app-network:
    name: myapp-network
    driver: bridge

services:
  nginx:
    image: nginx:alpine
    networks:
      - app-network
    # ... other config

  app:
    image: myapp:latest
    networks:
      - app-network
    # ... other config

Benefits:

• Predictable network names
• Easier to connect external containers
• Better documentation
• Easier troubleshooting

3. Document Port Mappings

Create a reference document for your team:

# Service Port Reference

## MyApp Service
- **Container Name:** myapp-nginx-1
- **Internal Port:** 8080 (what the app listens on)
- **Host Port:** 5001 (optional, for direct access)
- **Network:** myapp-network
- **Reverse Proxy Config:** myapp-nginx-1:8080
- **Domain:** myapp.example.com

Why this matters: When someone needs to troubleshoot or add a new service, they know exactly what ports to use.

4. Automate Network Connections

Create a script to ensure your reverse proxy is on all necessary networks:

#!/bin/bash
# connect-reverse-proxy.sh
# Ensures reverse proxy is connected to all service networks

REVERSE_PROXY_CONTAINER="nginx-proxy-manager"  # Adjust to your container name

NETWORKS=(
  "myapp-network"
  "auth-service-network"
  "api-service-network"
  # Add all your service networks here
)

for network in "${NETWORKS[@]}"; do
  if docker network inspect "$network" &>/dev/null; then
    docker network connect "$network" "$REVERSE_PROXY_CONTAINER" 2>/dev/null && \
      echo "✓ Connected to $network" || \
      echo "  Already on $network"
  else
    echo "⚠ Network $network does not exist"
  fi
done

Usage:

chmod +x connect-reverse-proxy.sh
./connect-reverse-proxy.sh

Why this matters: When you add new services, you can run this script to ensure connectivity without manual steps.

5. Test Before Cutover

Always test the new configuration before switching DNS or making it live:

Testing checklist:

1. ✅ Update reverse proxy configuration
2. ✅ Verify network connectivity
3. ✅ Test with internal IP or hosts file modification
4. ✅ Verify all functionality works
5. ✅ Check logs for errors
6. ✅ Monitor for a few minutes
7. ✅ Then update DNS or make live

Testing with hosts file (before DNS change):

# On your local machine, temporarily point domain to new server
sudo nano /etc/hosts
# Add: <new-server-ip> myapp.example.com

# Test
curl -I https://myapp.example.com

# If successful, update DNS
# Then remove hosts file entry

6. Version Control Your Configurations

Store your reverse proxy configurations in version control:

# Export Nginx Proxy Manager configs
docker exec nginx-proxy-manager tar czf /tmp/npm-configs.tar.gz /data/nginx/proxy_host/

# Copy to your machine
docker cp nginx-proxy-manager:/tmp/npm-configs.tar.gz ./npm-configs-backup-$(date +%Y%m%d).tar.gz

# Commit to git
git add npm-configs-backup-*.tar.gz
git commit -m "Backup NPM configs before migration"

Real-World Example: Service Migration

Let’s walk through a concrete example of migrating a service from a distributed setup to a consolidated one.

Before: Distributed Setup

Architecture:

• Reverse proxy on Server A (public-facing)
• Application service on Server B (private, via VPN)

Reverse Proxy Configuration:

# Nginx Proxy Manager config
set $forward_scheme http;
set $server         "192.168.1.100";  # External IP (different machine via VPN)
set $port           5001;               # Host-mapped port

Why this was necessary: The application was running on Server B, while the reverse proxy was on Server A. Traffic had to route across the VPN network using the server’s IP address.

Limitations:

• Requires VPN connectivity
• Port must be exposed on host
• Less resilient to network changes
• More complex troubleshooting

After: Consolidated Setup

Architecture:

• Reverse proxy and application service both on Server A

Reverse Proxy Configuration:

# Nginx Proxy Manager config
set $forward_scheme http;
set $server         "myapp-nginx-1";  # Container hostname (same Docker host)
set $port           8080;              # Internal container port

Why this is better: Both the reverse proxy and application are now on the same server. We can use Docker’s internal networking, eliminating the need for external IP routing and VPN traversal.

Benefits:

• No VPN required for internal routing
• Port doesn’t need to be exposed on host
• More resilient to network changes
• Simpler troubleshooting
• Better performance (no network hop)

The Migration Steps

1. Verify network connectivity:# Connect reverse proxy to application network docker network connect myapp-network nginx-proxy-manager # Verify connection docker network inspect myapp-network | grep nginx-proxy-manager
2. Update configuration (via web UI or database):
   • Change Forward Hostname/IP: 192.168.1.100 → myapp-nginx-1
   • Change Forward Port: 5001 → 8080
3. Verify DNS resolution:docker exec nginx-proxy-manager getent hosts myapp-nginx-1 # Expected: 172.31.0.3 myapp-nginx-1
4. Test connectivity:# From reverse proxy container docker exec nginx-proxy-manager wget -qO- http://myapp-nginx-1:8080
5. Reload reverse proxy:# For Nginx Proxy Manager docker exec nginx-proxy-manager nginx -s reload # Or restart container docker restart nginx-proxy-manager
6. Verify end-to-end:curl -I https://myapp.example.com

When to Use Each Approach

Use Container Hostnames When:

✅ Services are on the same Docker host (after consolidation)
✅ You want better network isolation
✅ You want to avoid port conflicts
✅ You want more portable configurations
✅ You’re using Docker Compose or similar orchestration
✅ You’ve migrated from a distributed setup to a consolidated one
✅ You want to reduce exposed attack surface

Use IP Addresses When:

✅ Services are on different physical hosts (original distributed setup)
✅ Services are connected via VPN or external network
✅ You’re proxying to non-Docker services
✅ You need to route through a load balancer
✅ You’re dealing with external services
✅ You haven’t yet consolidated services onto one host
✅ Services are in different data centers or cloud regions

Migration Path

If you’re consolidating services, you’ll transition from IP addresses (distributed) to container hostnames (consolidated) as part of the migration process:

Distributed Setup
    ↓
[Plan Migration]
    ↓
[Migrate Services]
    ↓
[Update Reverse Proxy: IP → Container Hostname]
    ↓
[Verify & Test]
    ↓
Consolidated Setup

Understanding Docker Networking (For Beginners)

If you’re new to Docker networking, here are the key concepts:

What is a Docker Network?

A Docker network is like a virtual LAN (Local Area Network) that allows containers to communicate with each other. By default, Docker creates an isolated network for each container, but you can create shared networks.

Container Hostnames

When containers are on the same Docker network, they can reach each other using their container names as hostnames. Docker’s built-in DNS resolves these names automatically.

Example:

# Container named "myapp-nginx-1" on network "myapp-network"
# Can be reached as: http://myapp-nginx-1:8080
# From any other container on the same network

Internal vs. External Ports

Internal Port (Container Port): The port your application listens on inside the container (e.g., 8080)

External Port (Host Port): The port exposed on the Docker host (e.g., 5001)

Port Mapping: 5001:8080 means host port 5001 maps to container port 8080

When using container hostnames: You use the internal/container port (8080), not the external/host port (5001).

Network Types

Bridge Network (default): Containers on the same bridge network can communicate. This is what you’ll use most often.

Host Network: Container shares the host’s network stack. Rarely needed.

Overlay Network: For Docker Swarm multi-host networking. Advanced use case.

For most scenarios, bridge networks are what you want.

Conclusion

The migration process itself is straightforward, but the upstream configuration detail is where many people stumble. The key takeaway:

When consolidating services from a distributed setup (multiple machines) to a single instance, you can and should switch from external IP addresses to container hostnames. For services on the same Docker host, always use container hostnames and internal ports. This provides better isolation, port independence, and network resilience.

The Migration Benefit: By consolidating services onto one instance, you eliminate the need for complex network routing and external IP addressing. This architectural improvement simplifies your infrastructure while improving performance and security.

By following this approach, you’ll have:

• ✅ More maintainable configurations
• ✅ Better security through network isolation
• ✅ Fewer port conflicts
• ✅ More portable setups
• ✅ Easier troubleshooting
• ✅ Better performance (no network hops)

The next time you’re migrating Docker services, remember: it’s not just about moving containers and volumes—it’s about understanding how your reverse proxy connects to them.

Whether you’re a beginner learning Docker networking or an experienced engineer optimizing infrastructure, this nuance can make the difference between a smooth migration and hours of troubleshooting.

Additional Resources

Official Documentation

• Docker Networking Documentation
• Docker Compose Networking
• Nginx Proxy Manager Documentation
• Traefik Documentation
• Caddy Documentation

Learning Resources

• Docker Networking Deep Dive
• Understanding Docker Bridge Networks
• Reverse Proxy Best Practices

Tools

• Docker Network Inspector
• Container Network Analysis Tools

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Have you encountered similar challenges during migrations? What strategies worked best for you? Share your experiences and tips—this helps the entire community learn and improve!