6to4: easing the IPv6 transition

6to4 for labs; native dual-stack for database endpoints you care about.

6to4 gives IPv6 connectivity from public IPv4 via automatic tunnels — useful when native prefixes are unavailable.

Fine for

  • Lab dual-stack experiments
  • Early “can monitoring speak IPv6?” checks

Not for primary OLTP paths

Public 6to4 relays are an availability lottery. Prefer native dual-stack or a tunnel broker you control.

Database notes

  • Grants and bind-address must match the protocol clients use
  • Replication must not silently prefer a flaky 6to4 path
  • Label experimental interfaces as such

Bridge for learning. Do not stake primary database endpoints on relays you do not operate.