Docker v29.1.1: Critical DNS Fix

The docker 29.1.1 release notes detail a crucial maintenance update that shipped on November 28, 2025. This release addresses a critical networking regression introduced in a previous version that broke external DNS resolution on all custom bridge networks. The primary change is the reversion of a problematic pull request to restore proper DNS functionality. Users who rely on custom bridge networks for container communication with external services should prioritize this update to resolve DNS failures. This fix prevents cascading issues in microservices architectures where containers need to resolve external hostnames for API calls, database connections, and service discovery.

This maintenance release is recommended for all Docker users running custom bridge networks. Upgrade now to restore broken DNS resolution that could impact container connectivity to external services.

What Changed

• Networking: Reverted a pull request that broke external DNS resolution on all custom bridge networks (moby/moby#51615).
• Notification Settings: Updated change notification settings functionality.

Why It Matters

• Network DNS resolution: Restores external DNS lookup capability for containers on custom bridge networks, enabling containers to resolve external hostnames for API calls and database connections.
• Network stability: Fixes a regression that could break service discovery and external API calls from containers, preventing application failures.
• Infrastructure reliability: Prevents cascading failures in microservices architectures dependent on network resolution, maintaining overall system health.

Who Should Upgrade

This release is particularly relevant for DevOps engineers and system administrators managing Docker environments with custom bridge networks. Teams running microservices architectures where containers need to communicate with external APIs, databases, or services should prioritize this update. Anyone experiencing DNS resolution failures on custom bridge networks since upgrading to Docker 29.1.0 should apply this fix immediately.

How to Upgrade

1. Backup current Docker configuration and container state
2. Review the specific networking fix in GitHub pull request #51615
3. Update Docker using your platform’s package manager (e.g., apt-get upgrade docker-ce)
4. Restart the Docker daemon to apply changes
5. Test DNS resolution on custom bridge networks
6. Monitor container networking functionality in staging before production deployment

Known Issues

• No known issues reported in official notes for this release.

Feature Flow

Official Release Notes

View full docker 29.1.1 release notes on GitHub →