Understanding the iptables Tree View
📊 Structure
Tables - Top-level organization (filter, nat, mangle, raw)
Chains - Processing pipelines within tables (INPUT, OUTPUT, FORWARD, etc.)
Rules - Individual firewall rules that match and act on packets
Nested Chains - Custom chains are shown indented under rules that jump to them
🔄 Compression & Simplification
Inline Chains - Custom chains are nested directly under the rules that reference them
Same-Target Compression - Multiple consecutive rules with the same target are grouped together
Docker Enrichment - Container names (🐳) and network names (🐋) are shown when available
🏷️ Symbols & Indicators
✅ ACCEPT - Traffic is allowed through
❌ DROP/REJECT - Traffic is blocked
🐳 Container - Docker container name
🐋 Network - Docker network name
🏠 Private IP - Internal network address
🔁 Loopback - Local traffic (127.0.0.1)
→ JUMP - Rule jumps to another chain
⚡ RETURN - Returns to calling chain
💡 Tip: Rules are evaluated top-to-bottom. The first matching rule determines the action.
Indented chains show the flow when a rule jumps to a custom chain.