Templates reference a config file with the GNS3_IOL_STARTUP_CONFIG
environment knob; the controller materializes the file content into
startup_config_content on node creation (sent once, knob consumed —
the same pattern as the IOU startup_config mapping). The compute builds
the content into the node's nvram_<app id> at the next start using the
IOU nvram_import utility (IOL and IOU share the nvram container format,
verified against iol-xe 17.18.02): valid config at boot, no setup
dialog, %h hostname substitution, hostname rewrite on rename.
Semantics verified against the runner: IOL boots from NVRAM whenever it
holds a config, so a plain stop/start never re-applies the startup
config and 'write memory' survives restarts; an explicit content edit
(PUT) is re-applied on the next start and wins over the saved config,
like IOU.
IOL interface MACs derive from the application ID (aabb.cc{app}{iface}),
so ids must be unique across opened projects sharing computes — the same
reason IOU has its allocator. IOL Docker nodes draw from the upper half
(512-1022, netiomux's fixed peer is 1023) so the two node types can
neither collide nor starve each other; IOU behavior is unchanged.
The controller sniffs the same GNS3_IOL_RUNNER environment marker the
compute uses to select IOLDockerVM (both the nested-properties and
template/top-level-kwarg shapes), stores the id in node properties like
IOU does, and passes it through the Docker create payload. Without an
allocation the compute falls back to a stable node-derived id in the
same upper range.
IOL derives interface MACs from its application ID. With a constant
local-app every node shared the same MACs, and linked routers dropped
each other's frames as MAC loops — ARP never resolved and pings were
100% lost even though the whole uBridge datapath was forwarding.
Derive local-app from the node UUID (stable across restarts, kept in
1..1022) and align remote-app with the netiomux convention CML uses
(1023). Verified end to end: two iol-xe nodes, Ethernet0/0 link,
ARP resolves both ways, ping 4/5 (first loss = ARP), graceful
stop/start keeps the NVRAM config.
IOL interfaces come in 4-port units (Ethernet0/0-3, Ethernet1/0-3, ...),
addressed like IOU as (adapter_number, port_number 0-3):
- IOLDockerVM builds EthernetAdapter(interfaces=4) per adapter and asks
the runner for adapters x 4 interfaces (num-eth).
- DockerVM threads port_number through the NIO/capture API (the compute
routes parsed it from the URL but dropped it); single-port adapters
keep the historical bridge{N} names and command sequence, multi-port
adapters get one bridge per port (bridge{a}_{p}).
- The unix-socket NIO wiring addresses sockets flat across adapters:
adapter x ports-per-adapter + port, so single-port images keep their
exact socket layout.
- The controller port list for GNS3_IOL_RUNNER docker nodes is generated
by StandardPortFactory with the IOU naming (Ethernet{segment0}/{port0},
segment size 4); plain docker nodes keep eth{N}.
_get_container_ifname only names the kernel interface inside the
container's network namespace (single call site: docker move_to_ns) -
IOL never uses that path, and the controller port list never reads it.
Name the ports through the template's custom_adapters instead (the
mechanism SR Linux appliances use for mgmt0/e1-1): adapter N shows as
Ethernet{N/4}/{N%4}, matching the IOS CLI, with no server-side changes.
Name ports after the IOL interface they map to (Ethernet0/0, one 4-port
unit per adapter range) via the _get_container_ifname override point, so
the GNS3 UI matches the IOS CLI. Display only — the flat adapter number
remains the socket index.
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.
