Node Configuration
This document outlines various configuration options for the EN. Currently, the Node requires the definition of numerous environment variables. To streamline this process, we provide prepared configs for the ZKsync Era - for both mainnet and testnet. You can use these files as a starting point and modify only the necessary sections.
You can also see directory docker-compose-examples if you want to run external-node on your machine with recommended default settings.
Database
The Node uses two databases: PostgreSQL and RocksDB.
PostgreSQL serves as the main source of truth in the EN, so all the API requests fetch the state from there. The
PostgreSQL connection is configured by the DATABASE_URL
. Additionally, the DATABASE_POOL_SIZE
variable defines the
size of the connection pool.
RocksDB is used in components where IO is a bottleneck, such as the State Keeper and the Merkle tree. If possible, it is
recommended to use an NVME SSD for RocksDB. RocksDB requires two variables to be set: EN_STATE_CACHE_PATH
and
EN_MERKLE_TREE_PATH
, which must point to different directories. When running a Node inside Docker Compose, Kubernetes
etc., these paths should point to dirs in a persistent volume (or 2 separate volumes). Persistent volumes must be
exclusive to a node; i.e., they must not be shared among nodes concurrently or transferred from one node to another.
Failing to adhere to this rule may result in RocksDB corruption or
the Node crashing on start.
L1 Web3 client
Node requires a connection to an Ethereum node. The corresponding env variable is EN_ETH_CLIENT_URL
. Make sure to set
the URL corresponding to the correct L1 network (L1 mainnet for L2 mainnet and L1 sepolia for L2 testnet).
Note: Currently, the Node makes 2 requests to the L1 per L1 batch, so the Web3 client usage for a synced node should not be high. However, during the synchronization phase the new batches would be persisted on the Node quickly, so make sure that the L1 client won’t exceed any limits (e.g. in case you use Infura).
Exposed ports
The dockerized version of the server exposes the following ports:
- HTTP JSON-RPC: 3060
- WebSocket JSON-RPC: 3061
- Prometheus listener: 3322
- Healthcheck server: 3081
While the configuration variables for them exist, you are not expected to change them unless you want to use the Node outside provided Docker environment (not supported at the time of writing).
API limits
There are variables that allow you to fine-tune the limits of the RPC servers, such as limits on the number of returned entries or the limit for the accepted transaction size. Provided files contain sane defaults that are recommended for use, but these can be edited, e.g. to make the Node more/less restrictive.
Some common API limits config:
EN_MAX_RESPONSE_BODY_SIZE_MB
(default is 10 i.e. 10MB) controls max size of a single response. Hitting the limit will result in errors similar to: “Response is too big (…)”.EN_MAX_RESPONSE_BODY_SIZE_OVERRIDES_MB
overrides max response size for specific RPC methods. E.g., setting this var toeth_getLogs=100,eth_getBlockReceipts=None
sets max response size foreth_getLogs
to 100MB and disables size limiting foreth_getBlockReceipts
, while other RPC methods will use theEN_MAX_RESPONSE_BODY_SIZE_MB
setting.EN_REQ_ENTITIES_LIMIT
(default 10,000) controls max possible limit of entities to be requested at once. Hitting the limit will result in errors similar to: “Query returned more than 10000 results (…)”
JSON-RPC API namespaces
There are 7 total supported API namespaces: eth
, net
, web3
, debug
- standard ones; zks
- rollup-specific one;
pubsub
- a.k.a. eth_subscribe
; en
- used by Nodes while syncing. You can configure what namespaces you want to
enable using EN_API_NAMESPACES
and specifying namespace names in a comma-separated list. By default, all but the
debug
namespace are enabled.
Logging and observability
MISC_LOG_FORMAT
defines the format in which logs are shown:plain
corresponds to the human-readable format, while the other option isjson
(recommended for deployments).RUST_LOG
variable allows you to set up the logs granularity (e.g. make the Node emit fewer logs). You can read about the format here.MISC_SENTRY_URL
andMISC_OTLP_URL
variables can be configured to set up Sentry and OpenTelemetry exporters.- If Sentry is configured, you also have to set
EN_SENTRY_ENVIRONMENT
variable to configure the environment in events reported to sentry.