Kristoffer Dalby 5228818a12 integration: reproduce HA primary flap to offline node via docker disconnect ...

Add a docker-network-disconnect primitive — `DisconnectFromNetwork`
/ `ReconnectToNetwork` on `TailscaleClient`, backed by
`pool.Client.DisconnectNetwork` — so an integration test can
faithfully simulate the cable-pull scenario the issue reporter
observed in Proxmox. Iptables-based simulations leave the socket
open at the container kernel and miss the bug.

Use it in `TestHASubnetRouterFailoverDockerDisconnect` to assert
the no-flap invariant: once primary has failed over from r1 to r2
and r2 also loses connectivity, primary must not switch back to
the still-offline r1. The assertion fails on the current branch —
the all-unhealthy fallback in `electPrimaryRoutes` flips primary
to the lowest-NodeID candidate regardless of online state. Locking
the failure in via TDD before designing the fix.

Updates #3203

2026-04-29 12:25:40 +00:00

..

tsic.go

integration: reproduce HA primary flap to offline node via docker disconnect

2026-04-29 12:25:40 +00:00