The SKIP_INIT volume bridge replicated init.sh's seed + mount --bind script
via docker exec *after* the container started. That copied the mechanism but
not the invariant that makes init.sh safe — the entrypoint position, which
guarantees the volume is in place before the application runs. The exec runs
concurrently with the NOS boot, so whether the NOS loaded its persisted
config or the overlay's factory copy was a timing race:
- single node stop/start on an idle system won it (exec ~1s, SR Linux reads
its startup config at ~2-4s) — the save/stop/start round-trip passed;
- a server restart + project reload lost it (concurrent node starts queue on
the Docker API, delaying the exec by seconds) — SR Linux booted factory
while the persisted config.json sat intact on the host;
- XRd was immune (systemd boots tens of seconds before XR touches
/xr-storage), which is why the race was never observed on it.
Replace the bridge entirely:
- new DockerVM._prepare_volumes hook (no-op in the base class) runs in
create() after the image is present, before the container is created;
VendorDockerVM overrides it to seed each volume's host directory from the
image (throwaway docker create container + docker cp -a, nothing
executes). The .gns3_perms marker gates the seeding: a volume that ever
started is never re-seeded, so saved configuration is never overwritten
with factory content (also the upgrade path for existing nodes).
- VendorDockerVM._mount_binds now binds the volumes directly at their real
in-container paths (/etc/opt/srlinux) instead of /gns3volumes aliases, so
the persisted config is visible to the NOS from the very first process.
- _setup_skip_init_volumes and its start() call are gone; the container-side
_fix_permissions targets the volume paths directly (the direct binds
exist for the whole container lifetime, unlike the old bridge).
The volume-list computation (validation + overlap de-duplication) moves
into DockerVM._persistent_volume_list so create-time seeding and _mount_binds
cannot drift apart.
docker-exec-console.md gains a "Terminal geometry and size forwarding"
section: the WS binary control-frame protocol ({"cols","rows"} -> NAWS /
asyncssh resize), the tall 511x10000 default and when it is applied or
restored, the exec-creation race handling, the GNS3_CONSOLE_RESIZE=0
knob for paging CLIs, and the SR Linux flicker root cause with the
measured numbers (rows-driven ~2.4x output inflation on CPR-answering
clients; width-independent; sr_cli's scroll-append re-rendering is
inherent and identical outside GNS3).
vendor-nos-xrd.md: the appliance recipe now includes
GNS3_CONSOLE_RESIZE=0 with the rationale (shared exec + XR pager vs
browser resizes). New troubleshooting entry for the flicker symptom.
Document the SR Linux gns3a (35-adapter full chassis, matching
GNS3_INTERFACE_NAMES + custom_adapters), the three server-side schema fixes
needed for it to load (DockerConsoleType.docker_exec,
ApplianceV1_6.custom_adapters, extra_volumes docker-block passthrough), and
the symbol-theme behaviour that rewrites any :/symbols/-prefixed symbol to
the category default at load time (so router_cloud.svg cannot be used from
an appliance; use a custom symbol under symbols_path instead).
The reconnect-blank-screen bug: when sr_cli exited (quit / idle timeout /
crash) the while-true wrapper restarted it mid-session with no client
attached, so its startup CPR probe (\e[6n) went unanswered and the TUI
degraded/blocked. On reconnect lazy_started=True skipped recreation, so the
client saw a blank screen.
Fix: drop the while-true wrapper. Now when the CLI exits, the exec pty
closes (EOF), the broadcast task ends, and the next client connection
detects the dead upstream via _upstream_alive() and recreates the exec —
with a terminal attached, so CPR is answered. A live exec is reused
(just a Ctrl-L redraw).
_LazyExecTelnetServer is extracted from a closure to module level so the
reconnect/recreate logic is unit-testable. Add 9 tests covering
_upstream_alive states and the recreate-on-death / reuse-if-live /
close-half-dead-writer / no-while-true behaviors.
Full Docker suite (120) passes.
Override _mount_binds in VendorDockerVM: for GNS3_SKIP_INIT containers the
/etc/network volume (GNS3's own network config consumed by init.sh's ifup)
is dead weight — init.sh never runs and the NOS manages its own
interfaces. The override removes the bind, filters /etc/network out of
self._volumes (keeping GNS3_VOLUMES and the bridge/fix passes consistent)
and deletes the host-side skeleton directory created by the base class.
Without GNS3_SKIP_INIT the mount is kept, matching base behaviour.
_persistent_volumes() is removed — the mount override is now the single
filter point.
GNS3_SKIP_INIT containers never run init.sh, so /etc/network (GNS3's own
network config consumed by init.sh's ifup) has no consumer — the NOS
manages its own interfaces. VendorDockerVM._persistent_volumes() filters it
out for both _setup_skip_init_volumes and _fix_permissions, saving one
docker exec per pass. The shared _mount_binds is untouched, and without
GNS3_SKIP_INIT the full volume list is returned so behaviour matches the
base class.
Document why host-user ownership of volume files during runtime is
harmless for SR Linux (root processes, self-healing daemons like aaamgr
rewriting its managed files, ACL-based access) and the deviation from the
standard init.sh model, with the escape hatch of dropping the start-time
fix pass for strict-ownership NOS images.
Also document the boot-ordering caveat: the volume bridge comes up after
the NOS boots, so early boot reads overlay defaults — verify the
save/stop/start closed loop, and add troubleshooting entry #10 for config
present on the host but not applied after restart.
Document the aaamgr_local_user.json case: SR Linux's aaamgr daemon rewrites
the file during boot as the image's srlinux user (uid 1002) after the
start-time permission pass, leaving it unreadable until the stop-time pass.
Trace the warning to the file-browser API chain (Show in file manager ->
list_node_files -> magic.from_file) and note the impact is limited to the
file_type field.
The host-side pass could not work for unprivileged GNS3 processes: the
.gns3_perms marker is created root-owned by the container-side touch, and
chowning root-owned files from the host requires root.
Rewrite VendorDockerVM._fix_permissions to run the busybox
record/chmod/chown script inside the container (as root) on the
/gns3volumes bind-mount targets — they exist for the container's whole
lifetime and do not depend on the mount --bind bridge, so a container
restart can no longer make the fix hit the overlay copy. A
stopped/exited container is skipped (logged) instead of restarted; the
next start's pass fixes ownership.
Replace the container-side _fix_permissions for vendor NOS containers with a
host-side pass that walks the node's project directories directly (they are
the Docker bind-mount sources): records mode:uid:gid into .gns3_perms and
chowns to the GNS3 user. No docker exec, no container restart — the base
implementation restarts an exited container just to chown, and after the
restart the mount --bind bridge is gone so it would fix the overlay copy
instead of the host files.
The pass runs at start (after _setup_skip_init_volumes seeds and bridges the
volumes) so the controller can read project files while the node runs, and
again at stop for files written during runtime.
Update docker-exec-console.md: VendorDockerVM architecture, hook points,
class-selection factory, volume-persistence lifecycle, and new
troubleshooting entries.
