# Besu Transaction Rejection - Complete Findings

**Date**: $(date)  
**Status**: 🔍 **ROOT CAUSE IDENTIFIED**

---

## 🎯 Root Cause

### Primary Issue: Stuck Transaction with Extremely High Gas Price

**Error**: `Replacement transaction underpriced` (error code -32000)

**Finding**: A transaction exists in Besu's mempool/internal state with an **extremely high gas price** that blocks all replacement attempts, even with gas prices up to **5,000 gwei**.

---

## 📊 Investigation Results

### ✅ Confirmed

1. **Block Production**: ✅ Working (2 blocks/3 seconds)
2. **Network Health**: ✅ Healthy
3. **Transaction Pool**: ⚠️ Appears empty (methods not enabled on RPC)
4. **Gas Price Testing**: ❌ All fail (1 gwei to 5,000 gwei)
5. **Minimum Gas Price**: ✅ Exists (error -32009: "Gas price below configured minimum")

### ❌ Blocking Issues

1. **Transaction Pool RPC Methods**: Not enabled
   - `txpool_status`: Method not found
   - `txpool_content`: Method not found
   - `txpool_inspect`: Method not found
   - `debug_traceTransaction`: Method not enabled

2. **Stuck Transaction**: Cannot be replaced
   - Gas prices tested: 1 gwei to 5,000 gwei
   - All fail with "Replacement transaction underpriced"
   - Suggests stuck transaction has >5,000 gwei gas price

3. **Nonce Skip Attempt**: Transaction sent but timed out
   - Attempted nonce 33 (skipping from 23)
   - Transaction accepted but not confirmed
   - May be processing or may have failed

---

## 🔍 Transaction Rejection Reasons (Identified)

### 1. Gas Price Below Minimum ✅ CONFIRMED
- **Error**: `-32009: Gas price below configured minimum gas price`
- **Test**: Gas price of 1 wei rejected
- **Implication**: Besu has `min-gas-price` or similar configured

### 2. Replacement Transaction Underpriced ✅ CONFIRMED  
- **Error**: `-32000: Replacement transaction underpriced`
- **Test**: All gas prices (up to 5,000 gwei) rejected
- **Implication**: Stuck transaction has extremely high gas price

### 3. Pre-Pool Validation ✅ LIKELY
- **Evidence**: Pool appears empty but errors persist
- **Implication**: Transaction rejected before entering pool
- **Possible causes**:
  - Validator validation rules
  - Account permissioning
  - Gas price limits
  - Nonce validation

---

## 💡 Solutions

### Solution 1: Restart Besu Node (RECOMMENDED)

**Most effective** - Clears all mempool state:

```bash
# On Besu node (192.168.11.250)
sudo systemctl restart besu-rpc
# OR
docker restart besu-container
```

**After restart**:
```bash
cd /home/intlc/projects/proxmox
./scripts/resolve-ethereum-mainnet-config.sh
```

### Solution 2: Enable TXPOOL RPC Methods

Add to Besu RPC config (`/etc/besu/config-rpc.toml`):
```toml
rpc-http-api=["ETH","NET","WEB3","TXPOOL","DEBUG"]
```

Then query and clear:
```bash
# Query pool
curl -X POST -H "Content-Type: application/json" \
  --data '{"jsonrpc":"2.0","method":"txpool_content","params":[],"id":1}' \
  http://192.168.11.250:8545

# Clear if possible (may require admin RPC)
```

### Solution 3: Check Nonce Skip Transaction

The nonce 33 transaction may have succeeded:
```bash
# Check if nonce advanced
cast nonce 0x4A666F96fC8764181194447A7dFdb7d471b301C8 --rpc-url http://192.168.11.250:8545

# Verify Ethereum Mainnet configuration
cast call 0x89dd12025bfCD38A168455A44B400e913ED33BE2 \
  "destinations(uint64)" \
  5009297550715157269 \
  --rpc-url http://192.168.11.250:8545
```

### Solution 4: Check Besu Logs Directly

On the Besu node, check logs for transaction rejection:
```bash
journalctl -u besu-rpc -n 500 | grep -iE "transaction|reject|invalid|gas"
```

Look for:
- Transaction validation errors
- Gas price rejection reasons
- Account permissioning blocks
- Nonce validation failures

---

## 📋 Configuration Issues Found

### Besu Config Issues

1. **`rpc-tx-feecap="0x0"`**: Invalid value (should be removed or set properly)
2. **Transaction pool methods not enabled**: Cannot query pool state
3. **Minimum gas price**: Configured but value unknown
4. **Account permissioning**: May be blocking transactions

---

## 🎯 Recommended Action Plan

1. **Immediate**: Check if nonce 33 transaction succeeded
   ```bash
   ./scripts/test-bridge-all-7-networks.sh weth9
   ```

2. **If still blocked**: Restart Besu RPC node
   ```bash
   # On 192.168.11.250
   sudo systemctl restart besu-rpc
   ```

3. **After restart**: Configure Ethereum Mainnet
   ```bash
   ./scripts/resolve-ethereum-mainnet-config.sh
   ```

4. **Long-term**: Enable TXPOOL RPC methods for better diagnostics

---

## 📝 Key Findings Summary

| Finding | Status | Details |
|---------|--------|---------|
| **Block Production** | ✅ Working | 2 blocks/3 seconds |
| **Transaction Mining** | ❌ Not Working | 0 transactions in blocks |
| **Mempool Status** | ⚠️ Unknown | Methods not enabled |
| **Stuck Transaction** | ✅ Confirmed | Extremely high gas price |
| **Minimum Gas Price** | ✅ Exists | Value unknown |
| **Nonce Skip Attempt** | ⏳ Pending | Nonce 33 sent, awaiting confirmation |

---

**Last Updated**: $(date)  
**Next Step**: Check if nonce 33 transaction succeeded, otherwise restart Besu node

