René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"NS queries hang/fail silently on JDK 25 Linux (works on JDK 21)","articleBody":"Environment:\n  - dnsjava: 3.6.2\n  - JDK 25 (Eclipse Temurin), Linux (Alpine container on Debian 12 host)\n  - Spring Boot application, long-running process\n  - Resolver: ExtendedResolver with explicit servers (8.8.8.8, 1.1.1.1), no system DNS discovery involved\n\nWhat happens:\n\nNS queries issued via ExtendedResolver consistently fail or return no results when running under JDK 25 on Linux. No exception is thrown, queries appear to time out silently. The same code, same configuration, same DNS servers work correctly under JDK 21 without any changes.\n\nWhat we tried:\n  - Increased query timeout to 20s, no change\n  - Forced TCP transport, no change\n  - Switched dnsjava's NIO selector to poll() to address potential epoll edge-triggered race, no change\n  - Replaced virtual thread executors with a bounded platform thread pool, no change\n\nDowngrading the runtime from JDK 25 to JDK 21 resolves the issue immediately.","author":{"url":"https://github.com/anurlien1","@type":"Person","name":"anurlien1"},"datePublished":"2026-06-04T01:41:10.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/408/dnsjava/issues/408"}