📝 Update Phase 1 & 2 with Alpine-specific fixes (ash vs bash, rsync install, SSH key details)

Midori's Linux Dojo 🌸/Phase 1 - Walking/Exercises.md

@@ -68,28 +68,53 @@ uname -r                # Kernel version
 ## 🎯 Exercise 3 — File Permissions
 
 ```bash
-# Check permissions
-ls -la /root/lab/notes/
+# Step 1 — Check current permissions
 ls -la /root/lab/
 
-# Change permissions
-chmod 644 /root/lab/notes/hello.txt
-chmod 755 /root/lab/scripts
+# Step 2 — Understand the columns
+# -rw-r--r--  1  root  root  20  May 21  file
+# ─┬─ ─┬─ ─── permissions, owner, group, size, date, name
+#  │   └── user/group/other  (r=read, w=write, x=execute)
+#  └── file type (-=file, d=directory)
 
-# Create a script
+# Step 3 — Create a script
+# ⚠️ Alpine uses ash, NOT bash! Use #!/bin/sh
+mkdir -p /root/lab/scripts
 echo '#!/bin/sh' > /root/lab/scripts/sayhello.sh
 echo 'echo "Hello from a script!"' >> /root/lab/scripts/sayhello.sh
+# 🔴 If you use #!/bin/bash it will say "not found"!
+
+# Step 4 — Check permissions before making it executable
+ls -la /root/lab/scripts/sayhello.sh
+# Try to run it — should fail (no +x)
+./root/lab/scripts/sayhello.sh || echo "Failed! Need +x permission"
+
+# Step 5 — Add execute permission
 chmod +x /root/lab/scripts/sayhello.sh
+ls -la /root/lab/scripts/sayhello.sh
 ./root/lab/scripts/sayhello.sh
 
-# Test permissions
+# Step 6 — Change permissions with numeric mode
+chmod 644 /root/lab/scripts/sayhello.sh
+ls -la /root/lab/scripts/sayhello.sh
+
+# Step 7 — Remove execute permission
 chmod -x /root/lab/scripts/sayhello.sh
-./root/lab/scripts/sayhello.sh   # What happens?
+./root/lab/scripts/sayhello.sh || echo "Permission denied!"
+
+# Step 8 — Work with directories (need +x to enter)
+mkdir -p /root/lab/secret
+echo "classified" > /root/lab/secret/data.txt
+chmod 700 /root/lab/secret
+ls -la /root/lab/ | grep secret
+ls /root/lab/secret
 ```
 
 ### 📝 Questions:
-1. What do the numbers `644`, `755`, and `+x` mean?
-2. What happens when you remove execute permission from a script?
+1. What does `ls -la` show? Describe each column.
+2. What does `+x`, `-x`, `644`, `755`, `700` mean?
+3. Why does a script need `+x` but `cat file.txt` doesn't?
+4. Why does a directory need `+x` to be accessible?
 
 ---
 

Midori's Linux Dojo 🌸/Phase 2 - Networking/Exercises.md

@@ -1,6 +1,6 @@
 # 🌐 Phase 2: Networking
 
-> Goal: Machines communicate — ping, SSH, file transfers
+> Goal: Machines communicate — ping, SSH, file transfers, services
 
 ---
 
@@ -18,50 +18,76 @@ 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
+# tcpdump (packet capture) — Alpine needs install first
+apk add tcpdump
+tcpdump -i eth0 -c 5 icmp &
+ping -c 3 10.0.1.2
 ```
 
 ### 📝 Questions:
 1. What's the MAC address of the other VM?
 2. Can you ping alpine-hop (10.0.1.3) from alpine-1?
+3. What subnet are you on? How many usable hosts?
 
 ---
 
 ## 🎯 Exercise 2 — SSH Keys
 
 ```bash
-# Generate an SSH key
+# Step 1 — Generate an SSH key pair
 ssh-keygen -t ed25519
+# Press Enter for all prompts (no passphrase)
 
-# Copy to the other VM
+# Step 2 — What just got created?
+ls -la ~/.ssh/
+# id_ed25519      ← your PRIVATE key (NEVER share this!)
+# id_ed25519.pub  ← your PUBLIC key (safe to share)
+
+# Step 3 — Copy your public key to alpine-2
 ssh-copy-id root@10.0.1.2
+# Enter root password for alpine-2 when prompted
 
-# Test passwordless login
+# Step 4 — Test passwordless login!
 ssh root@10.0.1.2 'hostname; uptime'
+# Should work WITHOUT asking for a password 🎉
+
+# Step 5 — See what ssh-copy-id did
+ssh root@10.0.1.2 'cat ~/.ssh/authorized_keys'
 ```
 
+### 💡 How it works
+Your public key is appended to `~/.ssh/authorized_keys` on the target. When you SSH, the server checks if you have the matching **private key** — no password needed! 🔑
+
 ---
 
-## 🎯 Exercise 3 — File Transfer
+## 🎯 Exercise 3 — File Transfer (SCP & RSYNC)
 
 ```bash
-# SCP (secure copy)
-echo "Secret message" > /root/secret.txt
-scp /root/secret.txt root@10.0.1.2:/root/
+# SCP — single files
+echo "CCNA study notes" > /root/study.txt
+scp /root/study.txt root@10.0.1.2:/root/
 
-# RSYNC (sync directories)
+# Verify
+ssh root@10.0.1.2 'cat /root/study.txt'
+
+# RSYNC — directories (need to install on Alpine)
+apk add rsync
 rsync -av /root/lab/ root@10.0.1.2:/root/lab-backup/
+
+# Verify the backup
+ssh root@10.0.1.2 'ls -la /root/lab-backup/'
 ```
 
+### 📝 Questions:
+1. What's the difference between `scp` and `rsync`?
+2. What does the `-a` flag in `rsync -av` mean? (hint: check `man rsync`)
+
 ---
 
 ## 🎯 Exercise 4 — Network Services
 
 ```bash
-# Check listening ports
+# Check what's listening on your VM
 ss -tlnp
 
 # Start a simple HTTP server on alpine-1
@@ -70,16 +96,33 @@ python3 -m http.server 8080 &
 # Access it from alpine-2
 curl http://10.0.1.1:8080/
 
-# Kill the server
+# See the connection in your server logs
+# Kill the server when done
 kill %1
 ```
 
 ---
 
+## 🎯 Bonus: CCNA Challenge
+
+```bash
+# From alpine-1, can you SSH to alpine-hop?
+ssh root@10.0.1.3
+
+# Check the routing table
+ip route
+
+# Why can alpine-1 reach alpine-hop (10.0.1.3)?
+# Why can't alpine-1 reach the internet?
+```
+
+---
+
 ## ✅ Phase 2 Checklist
-- [ ] Ping between VMs
-- [ ] SSH key-based auth
+
+- [ ] Ping and ARP (`ip neigh`)
+- [ ] SSH key generation and passwordless login
 - [ ] File transfer with `scp` / `rsync`
-- [ ] Network services
+- [ ] Running a network service
 
 **Previous:** [[Phase 1 - Walking]] | **Next:** [[Phase 3 - Users and Files]]