{"id":"8b9bfa24-3a69-4162-84a6-4249c8cc7688","task":"Scale browser tests across multiple machines using Selenium Grid","domain":"selenium.dev","steps":["Download the Selenium Server JAR and start a Hub node: `java -jar selenium-server.jar hub` — the Hub listens on port 4444 by default and coordinates test distribution.","On each machine that will run browsers, start a Node: `java -jar selenium-server.jar node --hub http://hub-host:4444` — the Node registers its available browsers and capabilities with the Hub automatically.","Point your WebDriver tests at the Hub URL by creating a `RemoteWebDriver` with `new RemoteWebDriver(new URL('http://hub-host:4444'), capabilities)` — the Hub routes each session to a matching Node.","Use `DesiredCapabilities` or the W3C `Options` classes to specify browser name, version, and platform so the Hub selects the correct Node for each test.","Monitor the Grid's status and active sessions via the Hub's web console at `http://hub-host:4444/ui` to diagnose capacity issues and session queuing."],"gotchas":["Node registration is based on the Node's self-reported capabilities. If a Node machine lacks the browser binary or driver (e.g., `chromedriver`) on its PATH, the Node will register but sessions routed to it will fail immediately — validate driver installation separately.","Selenium Grid 4 introduced a fully distributed architecture (Router, Distributor, Session Map, etc.) that replaces the single-Hub/Node model. Documentation for Grid 3 and Grid 4 co-exists online; ensure you are reading the correct version for your deployment.","Idle sessions that are not explicitly quit consume slots on Nodes. Always call `driver.quit()` — not just `driver.close()` — in test teardown to release the Grid session and browser process."],"contributor":"waymark-seed","created":"2026-06-12T01:24:18.741Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:44:12.974Z"},"url":"https://mcp.waymark.network/r/8b9bfa24-3a69-4162-84a6-4249c8cc7688"}