uBridge cannot reach sockets bind-mounted from the node's projects
directory: the path exceeds AF_UNIX's 107-byte sun_path cap. The /proc
detour from the previous commit is a dead end too - the runner drops
from root to the server uid, which makes the process non-dumpable and
its /proc/<pid>/root unreadable for the unprivileged server.
Instead, mirror how CML itself runs the image (source=<scratch>/tmp,
target=/tmp in its node definition): bind a per-node directory from the
runtime directory (<XDG_RUNTIME_DIR>/gns3/unixio/<node-id>, next to the
uBridge control sockets) at the image's socket directory. The path is
short, the directory is owned by the server user (whom the agent drops
its privileges to), and it is removed with the node. A socket directory
covered by a persisted volume keeps working as before.
IOLDockerVM persists only /tmp/run (nested bind at /tmp/run) and cleans
stale sockets/netio dirs from the socket directory on start, skipping
the cleanup when the container is already running. A failed wiring now
stops uBridge so the next start does not hit 'bridge already exist'.
The unix-socket NIO no longer requires the socket directory to be a
persisted volume: uBridge references the sockets through
/proc/<container-pid>/root<dir>/..., which is always well under the
107-byte sun_path cap (a project directory path alone exceeds it) and
leaves the sockets ephemeral in the container's own filesystem.
This replaces the runtime-dir symlink alias and its cleanup, and the
mount-time volume enforcement. IOLDockerVM now persists only /tmp/run
(the IOL working directory: startup-config + NVRAM) as a nested bind
instead of the whole /tmp; stale socket cleanup is gone with it, as
containers are recreated on every start.
Run Cisco CML containerized IOL images (e.g. iol-xe/iol-xe:17-18-02,
driven by virl.lab/cmd/iol-runner) as GNS3 Docker router nodes:
- VendorDockerVM: generic GNS3_UNIX_SOCKET_NIO/GNS3_UNIX_SOCKET_DIR knobs
wiring adapters through AF_UNIX datagram socket pairs
(add_nio_unix cNN.sock sNN.sock) instead of TAP + move_to_ns; node
creation fails if the socket dir is not a persisted volume.
- IOLDockerVM (GNS3_IOL_RUNNER=1): forces skip-init + unix-socket NIO +
/config,/tmp volumes, writes iol-config.json on every start (num-eth
tracks adapters, runner drops to the server uid/gid so the sockets are
reachable), pre-creates tmp/run, cleans stale sockets after unclean
kills, and makes reload a graceful stop + full start (NVRAM flush +
rewiring). Console stays telnet on PID 1 stdio.
- Manager selects the node class from console_type or GNS3_* environment
markers (create-time, like console_type).
- Image-free tests (25) and feature documentation.
