proxyd

proxyd is an RPC proxy

• https://github.com/ethereum-optimism/infra/tree/main/proxyd

proxyd /etc/proxyd/proxyd.toml  ws_method_whitelist

• Changelog: https://github.com/ethereum-optimism/infra/blob/main/proxyd/CHANGELOG.md
• Config: https://github.com/ethereum-optimism/infra/blob/main/proxyd/config.go
  • Config example: https://github.com/ethereum-optimism/infra/blob/main/proxyd/example.config.toml
• Releases: https://github.com/ethereum-optimism/infra/tags

Features:

• Whitelists RPC methods (ws_method_whitelist)
• Routes RPC methods to groups of backend services
• Round-robin Load balance requests across backend services
• Automatically retries failed backend requests
• Cache immutable responses from backends
• Provides metrics to measure request latency, error rates

Consensus related:

• Track backend consensus (latest, safe, finalized blocks), peer count and sync state
• Re-write requests and responses to enforce consensus

• Applies rate limiting (SenderRateLimitConfig) on a per-sender basis to avoid being bombarded with signed transactions causing a DOS (Denial of Service) of the sequencer (Optimism Censorship Bug Disclosure)

Backend healthy

In proxyd a backend is considered healthy if it meets the following criteria

• Not banned
• Avg 1-min moving window error rate ≤ configurable threshold
• Avg 1-min moving window latency ≤ configurable threshold
• Peer count ≥ configurable threshold
• Latest block lag ≤ configurable threshold
• ast state update ≤ configurable threshold
• Not currently syncing

Logs

ERROR

• error forwarding request to backend
• Error forwarding RPC batch
• error serving requests
• error proxying websocket
• error writing clientConn message

WARN

• backend request failed, trying again
• backend banned - not healthy
• backend banned - unexpected block tags
• proxied requests' XFF header will not contain the proxyd ip address
• peer count responded with 200 and 0 peers
• failed request
• error updating backend
• backend broke consensus

INFO

• starting proxyd
• Updating CA certificates.
• Running CMD.

Activities

• Read Optimism Censorship Bug Disclosure

Related

• Consensus
• Emerald Dshackle load balancer
• dRPC
• Total number of primary candidates
• RedisConfig
• Fallback

See also

• proxyd, config, routing_strategy, consensus_aware (deprecated), SenderRateLimitConfig, Consensus awareness, ws_method_whitelist, backend healthy
• OP Stack: op-, op-geth, op-node, op-proposer, op-batcher, op-contracts, op-challenger, op-heartbeat, op-ufm, op-service, Snap Sync, op-conductor, op-dispute-mon