Johnathan Corgan 26a579b1c9 Claim a free address range for the sidecar network instead of hardcoding one ...

Making the sidecar network name unique per run exposed a latent problem
rather than causing a new one. With a fixed name, compose found any
existing network and reused it, which quietly masked the fact that the
address range was hardcoded. With a unique name there is nothing to
reuse, so the range is requested every time and the run fails outright if
anything already holds it.

Claim the range instead of assuming it. The suite now tries to create its
network on a candidate range and, if the daemon reports an overlap, moves
to the next candidate. The daemon's own address pool becomes the arbiter,
so two concurrent runs cannot land on the same range at all - as opposed
to a range derived from the run identifier, which only makes a collision
unlikely, and a collision is the precise failure being avoided.

The node addresses are derived from whichever range is claimed rather than
written alongside it, including the gateway address the isolation check
probes. Moved to a range that nothing in the tree claims and that sits
outside the daemon's default pool.

Only an overlap is worth advancing on. Any other creation failure is real
and is reported with the daemon's own message, rather than being retried
sixty-four times and buried - a lesson from a failure elsewhere in the
harness this week that was undiagnosable because its error output was
discarded.

All three nodes now attach to the pre-created network as external, so
teardown removes it explicitly.

Verified: three concurrent claims take three distinct ranges; a
non-overlap error fails fast rather than looping; the suite passes 18/18;
and the claimed gateway address is confirmed pingable when not firewalled,
so the isolation assertions still mean something.

2026-07-19 07:17:19 +00:00

..

test-sidecar.sh

Claim a free address range for the sidecar network instead of hardcoding one

2026-07-19 07:17:19 +00:00