How to run a local dev node

A local Arbitrum Nitro dev node can help you deploy and test smart contracts in a fully controlled environment. This how-to walks you through the process of deploying and running a full development environment on your local machine that includes a Nitro dev node, a dev-mode geth L1, and multiple instances with different roles.

Note that the node is now Stylus-enabled by default, and the setup instructions remain the same as for running a Stylus dev node.

Step 1. Install prerequisites

You'll need docker and docker compose to run your node. Follow the instructions in their site to install them.

Step 2. Clone the nitro-testnode repo

You'll need the release branch.

  `git clone -b release --recurse-submodules https://github.com/OffchainLabs/nitro-testnode.git && cd nitro-testnode`

Step 3. Run your node

./test-node.bash --init

Step 4. Successive runs

To relaunch the node after the first installation, run the following command.

./test-node.bash

Clear local data

Note that running with the --init flag will clear all chain data and redeploy!

Rollup contract addresses and chain configuration

You can obtain the rollup chain configuration by running the following command. The chain configuration also includes the addresses of the core contracts.

docker exec nitro-testnode-sequencer-1 cat /config/l2_chain_info.json

You can find other available configuration files by running:

docker exec nitro-testnode-sequencer-1 ls /config

Token bridge

An L1-L2 token bridge can be deployed by using the parameter --tokenbridge. The list of contracts can be found by running:

docker compose run --entrypoint sh tokenbridge -c "cat l1l2_network.json"

Running an L3 chain

An L3 chain can be deployed on top of the L2 chain, by using the parameter --l3node. Its chain configuration can be found by running:

docker exec nitro-testnode-sequencer-1 cat /config/l3_chain_info.json

When deploying an L3 chain, the following parameters are also available:

--l3-fee-token: Uses a custom gas token for the L3 (symbol $APP), deployed on L2 at address 0x9b7c0fcc305ca36412f87fd6bd08c194909a7d4e --l3-token-bridge: Deploys an L2-L3 token bridge. The list of contracts can be found by running docker compose run --entrypoint sh tokenbridge -c "cat l2l3_network.json".

Additional arguments

You can find a list of additional arguments to use with test-node.bash by using --help.

./test-node.bash --help

Helper scripts

The repository includes a set of helper scripts for basic actions like funding accounts or bridging funds. You can see a list of the available scripts by running:

./test-node.bash script --help

If you want to see information of a particular script, you can add the name of the script to the help command.

./test-node.bash script send-l1 --help

Here's an example of how to run the script that funds an address on L2. Replace 0x11223344556677889900 with the address you want to fund.

./test-node.bash script send-l2 --to address_0x11223344556677889900 --ethamount 5

Blockscout

Nitro comes with a local Blockscout block explorer. To access it, add the param --blockscout when running your node.

./test-node.bash --blockscout

The block explorer will be available at http://localhost:4000

Default endpoints and addresses

Node RPC endpoints are available at:

Node	Chain id	RPC endpoint
L1 geth devnet	1337	http://localhost:8545
L2 nitro devnet	412346	http://localhost:8547 and ws://localhost:8548
L3 nitro (if enabled)	333333	http://localhost:3347

Some important addresses:

Role	Public address	Private key
Sequencer	0xe2148eE53c0755215Df69b2616E552154EdC584f	0xcb5790da63720727af975f42c79f69918580209889225fa7128c92402a6d3a65
Validator	0x6A568afe0f82d34759347bb36F14A6bB171d2CBe	0x182fecf15bdf909556a0f617a63e05ab22f1493d25a9f1e27c228266c772a890
L2 rollup owner	0x5E1497dD1f08C87b2d8FE23e9AAB6c1De833D927	0xdc04c5399f82306ec4b4d654a342f40e2e0620fe39950d967e1e574b32d4dd36
L3 rollup owner (if enabled)	0x863c904166E801527125D8672442D736194A3362	0xecdf21cb41c65afb51f91df408b7656e2c8739a5877f2814add0afd780cc210e
L3 sequencer (if enabled)	0x3E6134aAD4C4d422FF2A4391Dc315c4DDf98D1a5	0x90f899754eb42949567d3576224bf533a20857bf0a60318507b75fcb3edc6f5f
Dev account (prefunded with ETH in all networks)	0x3f1Eae7D46d88F08fc2F8ed27FCb2AB183EB2d0E	0xb6b15c8cb491557369f3c7d2c287b053eb229daa9c22138887752191c9520659

You can fund other addresses by using the scripts send-l1 and send-l2 as explained here.

Private keys publicly known

Do not use any of these addresses in a production environment.

Optional parameters

Here, We show a list of the parameters that might be useful when running a local devnode. You can also use the flag ./test-node.bash --help to get them.

Flag	Description
--build	Rebuilds Docker images
--dev	Builds Nitro and Blockscout Dockers from source instead of pulling them. Disables simple mode
--init	Removes all the data, rebuilds, and deploys a new rollup
--pos	L1 is a proof-of-stake chain (using Prysm for consensus)
--validate	Validates all blocks in WASM, heavy computation
--l3node	Deploys an L3 node on top of the L2
--l3-fee-token	Sets up the L3 chain to use a custom fee token. Only valid if --l3node flag is provided
--l3-fee-token-decimals	Number of decimals to use for a custom fee token. Only valid if --l3-fee-token flag is provided
--l3-token-bridge	Deploys an L2-L3 token bridge. Only valid if --l3node flag is provided
--batchposters	Batch posters [0-3]
--redundantsequencers	Redundant sequencers [0-3]
--detach	Detaches from nodes after running them
--blockscout	Builds or launch the Blockscout
--simple	Runs a simple configuration. One node as a sequencer/batch-poster/staker (default unless using --dev)
--tokenbridge	Deploy an L1-L2 token bridge
--no-tokenbridge	Opt out of building or launching the token bridge
--no-run	Does not launch nodes (useful with build or init)
--no-simple	Runs a full configuration with separate sequencer/batch-poster/validator/relayer