The live suite asserted the datapath over IPv4 only. Give every guest a
ULA IPv6 address next to its v4 one and twin every v4 assertion point,
sharing the impairment window (one filter application, both families
asserted) so the runtime grows by minutes, not double.
- harness: configure_ios(eth_ipv6=), ping() dispatches to `ping ipv6`,
docker_bring_up_ipv6 (the Docker daemon leaves eth0 with
disable_ipv6=1 on v6-less bridge networks, so the interfaces-file
route cannot work), family-aware docker_wait_address, pcap_records
scans every record (a leading DAD/MLD frame must not mask the
sampled ethertype), and pcap_icmp_rtt measures the wire round trip
from capture timestamps;
- scenarios: connectivity/delay/suspend/isolation/churn checks in both
families, captures assert 86dd next to 0800, the libpcap bpf drops
are asserted family-selective (icmp vs icmp6, each killing its own
family and leaving the other alive), the eBPF classifier modes on
both families, marker v6 twins with an echo-specific expression
(bare icmp6 also matches DAD/MLD and would break the exact counts),
the v6 sharkd replay, and the link-local matrix gains the 86dd
all-nodes row; serial (HDLC) legs stay v4-only;
- the dynamips-emulated classic IOS under-reports its `ping ipv6` RTT
by ~40 % of a delayed round trip (pcap-verified: the wire carries the
v6 echo exchange in the same ~230 ms as v4 while the console reports
~130 ms), so the dynamips-family scenarios assert the v6 delay from
the capture's own timestamps — recorded in tests/e2e/README.md.
Full suite: 17 passed in 58m50s.
The 'impairment cleared' asserts used avg < 50 on three-packet IOS pings;
the unimpaired baseline is 20-45 ms with 4 ms quantization, and host
scheduling jitter pushed averages to 54/56 in two full-suite runs
(esw, dynamips) — a margin, not an impairment (the qdisc asserts pass,
success is 100 %). The contrasted delayed regime is >= 150 ms, so a
100 ms bound still separates the two cleanly. Docker's sub-millisecond
veth asserts keep their 50 ms bound (three orders of magnitude of
headroom, never observed to flake).
Same guard the ethernet-switch scenario already carries: NetworkManager
can release an NM-managed TAP from its bridge shortly after
(re-)enslavement (docs/bugs/networkmanager-tap-release.md). Applied to
the Dynamips, QEMU, IOU, IOL-runner and switch-cascade scenarios after
their nodes have booted (no-op where nmcli/NetworkManager is absent).
This keeps those tests deterministic on un-declared hosts.
The L2-anchor spec's behavioral guarantee — an idle link stays silent for
5 s once the enslavement burst settles — only ran in the Dynamips and
Docker suites. It now also runs in QEMU, IOU, the IOL container, the
switch fast path and the switch cascade, which covers every host-device
creation path:
* tap create (Dynamips/QEMU/IOU anchors), docker create_veth (Docker host
ends; the cascade's race-loser end is hardened after create by the
server), bridge add_nio_tap (the IOL container anchor, the fifth
creator), and the brctl switch bridges, whose multicast snooping is off
precisely so the bridge role can reach silence;
* each scenario silences its guests first (IOS interfaces shut through
the console; Docker guests' links down) and re-verifies the ping after;
* the cascade measures 8 devices at once (four absorbed router anchors,
both cascade ends, both switch bridges).
IOL 158 s, cascade 293 s, ESW fast path 378 s, QEMU 428 s, IOU 308 s —
all green.
The filter matrix (cls_bpf, the eBPF classifier) only ran on Docker veth
host ends; the IOU and IOL-container scenarios now spot-check it on their
TAP anchors and prove a filter survives a node restart:
* bpf "icmp" drops everything with clsact on the anchor, both ends, and
clears back to an empty qdisc;
* frequency_drop 3 (the eBPF every-nth mode) measured 56 % round-trip
loss (1 - (2/3)^2 = 55.6 % expected) in both scenarios;
* the IOU test applies delay 100 before a router stop/start: the fresh
anchor gets netem back (tc level) and the restarted router's pings
measure RTT >= 150 ms until the filter is cleared (a re-attach that
dropped the filter would show ~100 ms).
IOU file 492 s, IOL file 182 s, both green.
The spec's gns3-server alignment section promised three assertions the
suites never carried; they land in harness.py and run in every kernel
scenario (plus the relay controls' anchor checks):
- E.1 assert_pure_l2: anchors and bridges carry no L3 identity (addrgenmode
none, no address in /proc/net/if_inet6, no ip -o -4 addr) -- the kernel
scenarios' anchors and per-link/switch bridges, relay-mode anchors and
the switch's relay TAPs alike (hardening is a creation-time property,
not a datapath one);
- E.2 assert_idle_silence (Dynamips suite): guest interfaces shut to
silence IOS's own CDP/keepalives, settle 2.5 s, then a 5 s window of
zero traffic over both anchors and the per-link bridge;
- assert_forwarding: every attached port reports brport/state == 3 -- a
bridge left DOWN keeps its ports disabled and forwards nothing, with no
error anywhere; the assertion is the only signal.
harness.l2only_supported() probes a throwaway uBridge once (link l2only
against a nonexistent device: 208 = command present, 202-Unknown command
= old build); without the command the assertions skip -- the spec's
degradation contract, mirroring the tc-capability skip.
The first live run caught a fifth-creator gap: the switch's relay port
TAPs (minted implicitly by bridge add_nio_tap) carried a live fe80::.
Delivered uBridge-side per the spec (fb72758: the transient TAP is
hardened at creation, attaches untouched); the server needed no change,
and the relay-control E.1 check is that creator's end-to-end coverage.
Two real iol-xe containers (Cisco CML iol-runner images, real IOS-XE on
the telnet console) against an isolated instance, the real uBridge with
the swappable bridge TAP leg:
* kernel link reports kernel_datapath; anchors exist from node start
and the per-link bridge enslaves exactly the two of them;
* real ICMP crosses the [unix <-> tap] port-bridge relay; delay 100
lands as netem on both anchors with the measured RTT growing >= 150 ms
and returning < 50 ms when cleared;
* suspend admin-downs the anchor and kills the traffic; resume
restores; AF_PACKET capture writes a real pcap;
* link delete/re-create swaps the port leg out and back in with the
ping returning; node stop leaves no gx devices and a start recreates
the whole wiring from the NIO; project delete cleans everything;
* the relay control on a relay-configured instance keeps the link off
the kernel and still pings (anchors may exist idle — the same
semantics as QEMU's and Dynamips' anchors: the server flag decides
attachment, not anchor birth).
Harness: create_iol_router (the appliance's template properties),
docker_images, iol_anchor_name, stage_iol_base_config (the shipped
iol-xe-base.txt copied into the isolated instance's configs dir — the
GNS3_IOL_STARTUP_CONFIG lookup path), boot_wait(straight_prompt=True)
for images that boot from NVRAM straight into the CLI with no 'Press
RETURN' sentinel, and GNS3_E2E_DEBUG=1 to run the isolated instance
with debug logging (the uBridge command stream lands in server.log —
how the ensure-anchor EBUSY was pinned down).
