# 🌐 Phase 2: Networking

> Goal: Machines communicate — ping, SSH, file transfers

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## 🎯 Exercise 1 — Ping & IPs

```bash
# Check your network
ip addr show eth0
ip route

# Ping the other lab VM
ping -c 4 10.0.1.2        # From alpine-1 → alpine-2
ping -c 4 10.0.1.1        # From alpine-2 → alpine-1

# Check ARP table
ip neigh

# Advanced network tools
ip addr                 # All interfaces
ip route                # Routing table
traceroute 10.0.1.2     # Path between VMs
```

### 📝 Questions:
1. What's the MAC address of the other VM?
2. Can you ping alpine-hop (10.0.1.3) from alpine-1?

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## 🎯 Exercise 2 — SSH Keys

```bash
# Generate an SSH key
ssh-keygen -t ed25519

# Copy to the other VM
ssh-copy-id root@10.0.1.2

# Test passwordless login
ssh root@10.0.1.2 'hostname; uptime'
```

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## 🎯 Exercise 3 — File Transfer

```bash
# SCP (secure copy)
echo "Secret message" > /root/secret.txt
scp /root/secret.txt root@10.0.1.2:/root/

# RSYNC (sync directories)
rsync -av /root/lab/ root@10.0.1.2:/root/lab-backup/
```

---

## 🎯 Exercise 4 — Network Services

```bash
# Check listening ports
ss -tlnp

# Start a simple HTTP server on alpine-1
python3 -m http.server 8080 &

# Access it from alpine-2
curl http://10.0.1.1:8080/

# Kill the server
kill %1
```

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## ✅ Phase 2 Checklist
- [ ] Ping between VMs
- [ ] SSH key-based auth
- [ ] File transfer with `scp` / `rsync`
- [ ] Network services

**Previous:** [[Phase 1 - Walking]] | **Next:** [[Phase 3 - Users and Files]]