smom-dbis-138/docs/deployment/BIDIRECTIONAL_CONFIGURATION_GUIDE.md

Bidirectional Bridge Configuration Guide

Date: 2025-01-18
Purpose: Complete guide for configuring full bidirectional bridge between ChainID 138 and Ethereum Mainnet

Overview

This guide provides step-by-step instructions for configuring both directions of the cross-chain bridge:

• ChainID 138 → Ethereum Mainnet
• Ethereum Mainnet → ChainID 138

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Prerequisites

Required

1. Admin Private Key: Must have access to bridge admin accounts
2. RPC Access:
   • Mainnet RPC: https://eth.llamarpc.com or similar
   • ChainID 138 RPC: http://192.168.11.211:8545 (VMID 2101)
3. Chain Selectors:
   • Mainnet: 5009297550715157269 ✅ (Known)
   • ChainID 138: See selector determination below

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Step 1: Determine ChainID 138 Selector

Option A: Use networks.json Value

From networks.json:

"chainSelector": "5009297550715157269"

Note: This is the same as Mainnet. Verify if correct for your CCIP implementation.

To use:

export CHAIN138_SELECTOR="5009297550715157269"
# Or add to .env:
echo "CHAIN138_SELECTOR=5009297550715157269" >> .env

Option B: Use Chain ID Directly (Custom CCIP)

For custom CCIP implementations, the selector may be the chain ID:

export CHAIN138_SELECTOR="138"
# Or add to .env:
echo "CHAIN138_SELECTOR=138" >> .env

Option C: Official Chainlink CCIP Selector

If using official Chainlink CCIP:

1. Query Chainlink CCIP Directory
2. Contact Chainlink for ChainID 138 registration
3. Use official selector provided

Helper Script

Run the helper script to check sources:

./scripts/configuration/find-chain-selector.sh

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Step 2: Configure ChainID 138 → Mainnet (Direction 1)

Status: ✅ Ready to execute (doesn't require ChainID 138 selector)

./scripts/configuration/configure-chain138-to-mainnet.sh

What it does:

• Configures WETH9 Bridge on ChainID 138 to send to Mainnet
• Configures WETH10 Bridge on ChainID 138 to send to Mainnet
• Uses Mainnet selector (5009297550715157269) which is known

Expected Output:

✓ WETH9 Bridge configured (ChainID 138 → Mainnet)
✓ WETH10 Bridge configured (ChainID 138 → Mainnet)

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Step 3: Configure Mainnet → ChainID 138 (Direction 2)

Status: ⚠️ Requires ChainID 138 selector

# Ensure CHAIN138_SELECTOR is set in .env or environment
./scripts/configuration/configure-mainnet-to-chain138.sh

What it does:

• Configures WETH9 Bridge on Mainnet to send to ChainID 138
• Configures WETH10 Bridge on Mainnet to send to ChainID 138
• Uses ChainID 138 selector (from environment)

Expected Output:

✓ WETH9 Bridge configured (Mainnet → ChainID 138)
✓ WETH10 Bridge configured (Mainnet → ChainID 138)

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Step 4: Full Bidirectional Configuration (Alternative)

Use the full configuration script (if selector is set):

# Ensure CHAIN138_SELECTOR is in .env
./scripts/configuration/configure-bridge-destinations.sh

This script configures both directions in one run.

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Step 5: Verify Configuration

Verify all bridge configurations:

./scripts/configuration/verify-bridge-configuration.sh

Expected Output:

• Mainnet bridges should show ChainID 138 selector in destinations
• ChainID 138 bridges should show Mainnet selector in destinations

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Configuration Summary

Bridge Addresses

Bridge	Mainnet Address	ChainID 138 Address
CCIPWETH9Bridge	0x3304b747E565a97ec8AC220b0B6A1f6ffDB837e6	0x3304b747E565a97ec8AC220b0B6A1f6ffDB837e6
CCIPWETH10Bridge	0x8078A09637e47Fa5Ed34F626046Ea2094a5CDE5e	0x8078A09637e47Fa5Ed34F626046Ea2094a5CDE5e

Chain Selectors

Chain	Selector	Status
Ethereum Mainnet	5009297550715157269	✅ Known
ChainID 138	See Step 1	⚠️ To be determined

Destination Configuration

ChainID 138 Bridges → Mainnet:

• Destination Selector: 5009297550715157269
• Receiver WETH9 Bridge: 0x3304b747E565a97ec8AC220b0B6A1f6ffDB837e6
• Receiver WETH10 Bridge: 0x8078A09637e47Fa5Ed34F626046Ea2094a5CDE5e

Mainnet Bridges → ChainID 138:

• Destination Selector: <CHAIN138_SELECTOR> (from Step 1)
• Receiver WETH9 Bridge: 0x3304b747E565a97ec8AC220b0B6A1f6ffDB837e6
• Receiver WETH10 Bridge: 0x8078A09637e47Fa5Ed34F626046Ea2094a5CDE5e

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Troubleshooting

Configuration Fails

Check:

• PRIVATE_KEY is set and correct
• Private key has admin access to bridges
• RPC endpoints are accessible
• ChainID 138 selector is correct

Error: "destination already exists":

• Destination may already be configured
• Verify with verify-bridge-configuration.sh

Error: "only admin":

• Private key doesn't have admin access
• Verify admin address: cast call <BRIDGE> "admin()" --rpc-url <RPC>

Selector Issues

If selector is incorrect:

1. Bridges can be reconfigured with correct selector
2. Use removeDestination() to remove incorrect entry
3. Use addDestination() with correct selector

To check current destinations:

cast call <BRIDGE_ADDRESS> "getDestinationChains()(uint64[])" --rpc-url <RPC>

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Testing After Configuration

Test ChainID 138 → Mainnet

1. Approve WETH9 on ChainID 138 for bridge
2. Send small amount via bridge
3. Verify receipt on Mainnet

Test Mainnet → ChainID 138

1. Approve WETH9 on Mainnet for bridge
2. Send small amount via bridge
3. Verify receipt on ChainID 138

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Quick Start (If Selector Known)

# 1. Set selector in .env
echo "CHAIN138_SELECTOR=5009297550715157269" >> .env  # Or appropriate value

# 2. Configure ChainID 138 → Mainnet
./scripts/configuration/configure-chain138-to-mainnet.sh

# 3. Configure Mainnet → ChainID 138
./scripts/configuration/configure-mainnet-to-chain138.sh

# 4. Verify
./scripts/configuration/verify-bridge-configuration.sh

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Status

✅ Configuration scripts ready

• ChainID 138 → Mainnet: Ready to execute
• Mainnet → ChainID 138: Ready to execute (requires selector)

⚠️ Selector determination needed

• See Step 1 for selector options
• Use helper script: find-chain-selector.sh

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Next Steps: Determine ChainID 138 selector and run configuration scripts for full bidirectional setup.