A live migration on 2026-08-24 stopped a production mail server and then
discovered the host's stalwart-cli was 0.13.4 - present, but from when the
CLI shipped with the server, with no `apply` command. The migration needs
v1.0.2+ from the separately-versioned stalwartlabs/cli repository.
Recovery was closed in both directions. v0.16's recovery-mode boot had
already bumped the store schema to v6, so the 0.15.5 binary refused to
reopen it ("expected 5 or below, found 6"). Going forward needed
export.json, which this tool's own failure path had deleted - and
regenerating it required a settings dump from a live v0.15 instance that
could no longer start. The operator restored a day-old snapshot and lost a
day of mail across nine domains.
Three fixes:
1. preflight.CheckExternalTools verifies stalwart-cli exists and is v1.0.2
or later, and that python3 runs - before anything is touched. Every fact
needed to prevent this was available in under a second from a stopped
state. Skipped for a patch upgrade, which invokes neither tool.
2. A failed run no longer deletes its work directory. Cleaning up on every
exit path was right for a sandboxed rehearsal and catastrophic here:
once the service is stopped the settings dump cannot be regenerated, so
deleting it removes the only way forward. The failure now prints the
resume command instead.
3. `run --resume <id>` continues an interrupted run. The checkpoint
machinery existed but never engaged, because run created a new run every
invocation - so a retry re-ran preflight against a binary already moved
aside, and failed. Completed steps are skipped from the checkpoint.
Proven against a VM built to match the failure: stalwart-cli 0.15.5,
accounts and mail seeded.
* preflight refused, service still active, mail still accepted
* a stub CLI passing --version and failing apply left the run stopped
with all eight inputs intact and the resume command printed
* --resume carried it to a clean finish: five seconds of downtime,
listeners regenerated, admin role restored, quotas rebuilt
That failure-path test is the one that should have run before production.
Every earlier test had stalwart-cli installed from the start, and the one
failure I did exercise happened to leave its artifacts behind.
jcoffey-dev
9faa21f4f1