`hermes gateway migrate --multiplex` ran its one fallible step LAST (install +
start the default gateway) with nothing around it. On a fleet whose secondary
ran a system unit as root (#110850) that step raised, leaving the flag on, the
secondary's unit removed and no gateway anywhere, and the re-run hit the
"already multiplexing (flag on)" short-circuit over an empty fleet.
- apply_migration(): the default bring-up runs inside a rollback. On failure the
manifest written before the first destructive step restores the flag and
reinstalls every recorded per-profile gateway with its recorded User=.
- MigrationPlan.interrupted: flag on + manifest present + no live default
gateway is a half-applied migration, not "already multiplexed"; the re-run
resumes from the manifest (target manager and User= read from it, since the
units themselves are gone) instead of refusing. Flag off + leftover manifest
refuses to overwrite it and points at --standalone.
- ProfileGateway.services records EVERY installed unit (user and system) and the
manifest carries them; apply stops/uninstalls all of them and rollback
reinstalls all of them, so a second owner is never left live beside the
multiplexer. The unattended hook treats a two-unit profile as an ambiguous
topology and refuses (review finding on #110205).
- gateway_identity(): an unresolvable User= on a system unit stays None instead
of borrowing the profile directory's owner; the unattended hook treats the
unknown principal as a boundary (review finding on #110205).
- auto_migration_opted_out(): reads the effective config (load_config_readonly
under the default home), so a managed `false` wins over a user `true` and a
YAML string "false" is an opt-out, not a truthy value (review finding on
#110205).
Builds on KoNit-K's #110854 (run_as_user threaded through install, preserved
from the removed system unit).
teknium1
8c82e93132