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lab/labsim/labsim-ipv6-ha-test.sh

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IPv6 was never HA, and the WAN becoming HA is what exposed it Reviewed the parked IPv6 task against the PPPoE-HA work of 2026-09-05/06. The gate that parked it ("WI-8 before IPv6") is cleared, but the same work invalidated the assumption the IPv6 design rested on. Verified on the live routers: vyos002 has no tun0, no he-tunnel-follow, no he-secrets, no VLAN 9 prefix and no route6 ::/0 -- only the pre-staged default-deny v6 firewall, which is correctly on both. Failover is now automatic and drill-proven, so every failover takes the whole v6 estate down for as long as vyos002 holds the VIP. Four things that came out of checking rather than reading: - PPPOE-HA.md's "tun0 survived untouched and IPv6 stayed up at 15.5ms" does not follow from its own premise and is corrected in place. The endpoint address is stable, but it MOVES to vyos002, which has nothing to decapsulate protocol 41. wan-drill had no IPv6 check at all, which is why nobody caught it. - A 22-second near-miss: vif53-pin-boot-disable bounced the 10 gig, he-tunnel- follow ticked once and saw the PPPoE address, and vyos-failover restored the route 22s before the second tick would have pointed HE at an address Vodafone reissues on every dial. - VyOS does NOT leave a tunnel down when its source-address is absent (the override's stated reason for leaving IPv6 single-homed). Measured in labsim: it commits rc=0 and brings the link UP -- a blackhole that attracts the v6 default route. The runtime gate is load-bearing, like the PPPoE gate. - The RA link-mtu was pinned at 1480 while the tunnel correctly drops to 1472 on the PPPoE path. Mechanism, mirroring PPPoE HA -- identical config on both, gated at runtime, no commit in the failover path: - vrrp-wan-reconcile: a v6 kernel plane. tun0 and radvd follow the VIP; radvd is stopped BEFORE the WAN goes so its farewell RA (router-lifetime 0) still has a path out. The WAN early-exits became if-blocks so the plane runs every tick. It deliberately does NOT call he-tunnel-follow: that would halve the hysteresis the near-miss above showed we depend on. - he-tunnel-follow: a master guard reading the same vrrp-wan.conf VIP, so the backup copy cannot point HE at its own idle PPPoE line, plus a stubbable HE_UPDATE_URL. - vrrp-wan-install carries both, so --check and the upgrade runbook cover IPv6. - wan-drill measures IPv6 in both timing loops and asserts zero HE API calls across a router failover. labsim finally has an HE endpoint, closing the gap the override itself cited as why this was never rehearsed. Both ISP islands already share the libvirt network, so that becomes the backbone and HE lives behind it on one address reachable over either WAN. Proven in the sim: backup tun=DOWN radvd=inactive, master tun=UP radvd=active, hysteresis then HE call then MTU 1480->1472, and VLAN 9 hosts autoconfiguring from the RA. The end-to-end v6 datapath is NOT yet proven -- inter-island transit crosses libvirt NAT and the return path is lost. Recorded as a KNOWN SIM GAP rather than papered over. The model change is staged, not merged: another agent runs pulumi up on that repo, and the gate must exist on vyos002 before the tunnel does. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01DMVzWZgiKW2wquf5z8S1yH
2026-09-06 14:30:44 +01:00
#!/bin/bash
# Does IPv6 follow VRRP mastership, and does it do so WITHOUT touching HE?
#
# The WAN became HA on 2026-09-06 and IPv6 did not follow it. Nothing caught
# that, because nothing tested it: wan-drill measured IPv4 only, and PPPOE-HA.md
# recorded "IPv6 stayed up at 15.5ms" from a reading taken outside the failover
# window. This is the matrix that would have caught it.
#
# TWO INVARIANTS, checked independently of any individual test:
#
# 1. At most ONE router ever has a live tunnel. An UP tunnel on a box that
# does not own the source address is not harmless -- see V4, it is a
# BLACKHOLE that will happily attract the v6 default route.
# 2. A ROUTER-level failover calls the HE API ZERO times. The 10 gig address
# is bound to a cloned MAC and follows the VIP to the other box unchanged,
# so there is nothing to tell HE. A non-zero count means something
# re-pointed the tunnel at a PPPoE address -- which the ISP re-issues on
# every dial, so it would be wrong within minutes.
#
# KNOWN SIM GAP, 2026-09-06 -- read this before believing a v6_online failure.
# The MECHANISM is proven here: tun0 up on the master and down on the backup,
# radvd following mastership, he-tunnel-follow's master guard, its hysteresis,
# its HE call and the 1480->1472 MTU switch, and VLAN 9 hosts autoconfiguring
# from the RA (observed: real SLAAC traffic from 2001:db8:187e:9::/64 arriving
# at the endpoint encapsulated).
#
# What is NOT yet proven is the end-to-end v6 DATAPATH, because the sim's
# "internet" is asymmetric: 6in4 packets from the PPPoE island reach the
# endpoint with an outer source of 192.168.122.1 -- the libvirt host's NAT --
# so HE's replies go back to the tunnel remote by a path with no NAT state and
# are lost. Forward works, return does not.
#
# That is a topology fault in the scaffold, not in the thing under test. Fixing
# it means giving the two ISP islands a real transit path that does not traverse
# libvirt NAT. Until then, treat v6_online failures as UNPROVEN rather than as
# evidence the design is wrong -- and do not let that ambiguity leak into
# production sign-off, which is exactly the mistake wan-drill made by asserting
# "IPv6 stayed up" from a reading taken outside the window.
#
# Requires the fake HE endpoint: ./labsim-he-endpoint.sh up
#
# ./labsim-ipv6-ha-test.sh --setup configure the router side (once)
# ./labsim-ipv6-ha-test.sh --list
# ./labsim-ipv6-ha-test.sh V1
# ./labsim-ipv6-ha-test.sh --all
set -uo pipefail
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
R1="${R1:-172.31.1.252}"; R2="${R2:-172.31.1.253}"
VIP="${VIP:-172.31.1.1}"
LAN9="${LAN9:-172.31.9.10}" # VLAN 9 client, for RA tests
HE_ADDR="${HE_ADDR:-192.0.2.10}"
HE_LINK6="${HE_LINK6:-2001:db8:1f1c:f6::1}"
RT_LINK6="${RT_LINK6:-2001:db8:1f1c:f6::2}"
V9_PREFIX="${V9_PREFIX:-2001:db8:187e:9}"
# Mirrors production: one MAC, one lease, whichever router holds the VIP.
WAN_MAC="${WAN_MAC:-02:9f:c2:12:9b:4f}"
PW="${VYOS_PW:-vyos}"; LANPW="${LANPW:-labsim}"
EVID="$SCRIPT_DIR/ipv6-ha-evidence"
HE="$SCRIPT_DIR/labsim-he-endpoint.sh"
SSH=(-o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null
-o LogLevel=ERROR -o ConnectTimeout=6 -o PreferredAuthentications=password)
r() { timeout 45 sshpass -p "$PW" ssh "${SSH[@]}" "vyos@$1" "${@:2}" 2>/dev/null; }
# The Alpine LAN VMs do not offer `password` auth -- reusing the routers' option
# set makes ssh exit 255 before running anything, which reads as "the network is
# broken". Same trap as lan() in labsim-pppoe-ha-test.sh.
LAN_SSH=(-o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null
-o LogLevel=ERROR -o ConnectTimeout=6)
lan9() { timeout 30 sshpass -p "$LANPW" ssh "${LAN_SSH[@]}" "root@$LAN9" "$@" 2>/dev/null; }
log() { printf '\033[36m==>\033[0m %s\n' "$*"; }
pass() { printf ' \033[32mPASS\033[0m %s\n' "$*"; }
fail() { printf ' \033[31mFAIL\033[0m %s\n' "$*"; FAILED=$((FAILED+1)); }
warn() { printf ' \033[33mWARN\033[0m %s\n' "$*"; }
FAILED=0
# --- observations ----------------------------------------------------------
# A destroyed or unreachable router is emphatically NOT holding the tunnel, but
# ssh returns an EMPTY string, and `[ "" = 0 ]` is false -- the pppoe matrix hung
# on exactly this waiting for a dead box to report zero. Default everything to 0.
tun_state() { local v; v="$(r "$1" "ip -br link show tun0 2>/dev/null | awk '{print \$2}'" | tr -d ' \n')"; echo "${v:-absent}"; }
tun_src() { r "$1" 'ip tunnel show tun0 2>/dev/null | sed -nE "s/.* local ([0-9.]+).*/\1/p"' | tr -d ' \n'; }
# Whichever router currently holds the 10 gig lease -- under the cloned MAC only
# one ever does. Read rather than assumed: the address changes when the MAC does.
tengig_addr() { local h a; for h in "$R1" "$R2"; do
a="$(r "$h" 'ip -4 addr show bond0.53 2>/dev/null | sed -nE "s/.*inet ([0-9.]+).*/\1/p"' | tr -d ' \n')"
[ -n "$a" ] && { echo "$a"; return; }
done; echo ""; }
tun_mtu() { local v; v="$(r "$1" 'cat /sys/class/net/tun0/mtu 2>/dev/null' | tr -d ' \n')"; echo "${v:-0}"; }
holder() { for h in "$R1" "$R2"; do
[ "$(r "$h" "ip -4 -o addr show | grep -c ' ${VIP}/'" | tr -d ' \n')" != 0 ] \
&& { echo "$h"; return; }; done; echo none; }
# Ask the ROUTER, not a client: a client can be answered by the wrong path.
v6_online() { [ "$(r "$1" "ping -6 -c1 -W3 $HE_LINK6 >/dev/null 2>&1 && echo y" | tr -d ' \n')" = y ]; }
radvd_on() { [ "$(r "$1" 'systemctl is-active radvd 2>/dev/null' | tr -d ' \n')" = active ]; }
he_calls() { timeout 60 "$HE" calls | tr -d ' \n'; }
# How many routers have a tunnel that is UP. Invariant 1's numerator.
tun_holders() { local n=0 h; for h in "$R1" "$R2"; do
case "$(tun_state "$h")" in UP|UNKNOWN) n=$((n+1)) ;; esac
done; echo "$n"; }
check_invariants() {
local t ok=0
t="$(tun_holders)"
[ "${t:-0}" -le 1 ] || { fail "INVARIANT: $t routers have tun0 up"; ok=1; }
return $ok
}
save_evidence() {
local name="$1"; local d="$EVID/$name"; mkdir -p "$d"
{ echo "=== $(date -Is) ==="
echo "--- HE endpoint ---"; timeout 60 "$HE" status
for h in "$R1" "$R2"; do echo "--- $h ---"
r "$h" 'sudo /config/vrrp-wan-reconcile --status 2>/dev/null
ip -br link show tun0 2>/dev/null; ip tunnel show tun0 2>/dev/null
ip -6 route show default; systemctl is-active radvd
sudo journalctl -t vrrp-wan -t he-tunnel-follow -n 10 --no-pager'
done; } > "$d/state.txt" 2>&1
log "evidence -> ipv6-ha-evidence/$name/"
}
# --- setup ------------------------------------------------------------------
# Applied through REAL VyOS config, unlike the ISP-side scaffold, because "will
# VyOS accept this?" is one of the questions being asked.
vyos_apply() { # host, then set-lines on stdin
local h="$1"
{ printf '#!/bin/vbash\nsource /opt/vyatta/etc/functions/script-template\nconfigure\n'
cat
printf 'commit\nsave\nexit\n'
} | timeout 90 sshpass -p "$PW" ssh "${SSH[@]}" "vyos@$h" \
'cat > /tmp/v6-apply.sh && chmod +x /tmp/v6-apply.sh && sudo /tmp/v6-apply.sh' 2>&1 | tail -3
# `vbash -c` never starts a config session and commit fails to stderr, which
# a helper like this discards -- the T4 matrix in labsim-pppoe-ha-test.sh ran
# its whole policy sweep against the default while printing the mode it
# thought it was testing. Always read the value back.
}
setup() {
log "--setup: router-side IPv6, both routers"
# THE CLONED MAC, first and on its own. Production pins f0:9f:c2:12:9b:4f on
# vif 53 so the 10 gig lease follows the VIP and the tunnel source is the
# SAME address on either box. The sim never had it -- each router took its
# own lease -- so the sim could not reproduce the one property the whole
# IPv6-HA design leans on, and invariant 2 would have been untestable here.
local h pref v9
for h in "$R1" "$R2"; do
log " $h: pinning the cloned WAN MAC $WAN_MAC"
vyos_apply "$h" <<EOF
set interfaces bonding bond0 vif 53 mac '$WAN_MAC'
EOF
done
# A new MAC means a NEW lease, so the tunnel source cannot be hardcoded --
# discover it. Hardcoding the pre-change address here would have configured
# every tunnel with a source neither router owns, i.e. the V4 blackhole, on
# both boxes, while the matrix reported setup success.
local src="" i
for i in $(seq 1 30); do
src="$(tengig_addr)"; [ -n "$src" ] && break
sleep 5
done
[ -n "$src" ] || { fail "no router took a 10 gig lease after the MAC change -- cannot set a tunnel source"; return 1; }
log " 10 gig lease under the cloned MAC: $src"
# Credentials pointing at the stub. HE_UPDATE_URL is read AFTER the secrets
# file is sourced, so putting it here overrides the production default
# without the script needing a sim-specific branch.
for h in "$R1" "$R2"; do
printf 'HE_USER=sim\nHE_UPDATE_KEY=sim\nHE_TUNNEL_ID=1\nHE_UPDATE_URL=http://%s/nic/update\n' "$HE_ADDR" \
| timeout 30 sshpass -p "$PW" ssh "${SSH[@]}" "vyos@$h" \
'cat > /tmp/he-secrets && sudo install -o root -g vyattacfg -m 0640 /tmp/he-secrets /config/he-secrets' >/dev/null
done
for h in "$R1" "$R2"; do
[ "$h" = "$R1" ] && { pref=high; v9=1; } || { pref=low; v9=2; }
log " $h (RA preference $pref, bond0.9 ::${v9})"
vyos_apply "$h" <<EOF
set interfaces tunnel tun0 encapsulation 'sit'
set interfaces tunnel tun0 source-address '$src'
set interfaces tunnel tun0 remote '$HE_ADDR'
set interfaces tunnel tun0 address '$RT_LINK6/64'
set interfaces tunnel tun0 mtu '1480'
set protocols static route6 ::/0 next-hop '$HE_LINK6'
set interfaces bonding bond0 vif 9 address '${V9_PREFIX}::${v9}/64'
set service router-advert interface bond0.9 prefix ${V9_PREFIX}::/64 preferred-lifetime '604800'
set service router-advert interface bond0.9 link-mtu '1472'
set service router-advert interface bond0.9 default-preference '$pref'
set system task-scheduler task he-tunnel-follow executable path '/config/he-tunnel-follow'
set system task-scheduler task he-tunnel-follow executable arguments 'run'
set system task-scheduler task he-tunnel-follow interval '1m'
EOF
done
# RA link-mtu is 1472, the PPPoE figure, on BOTH -- deliberately not 1480.
# It cannot be reconciled at runtime (it needs a commit, and the tunnel plane
# is commit-free on purpose), so advertise the lower of the two paths and be
# correct on either WAN. Production pinned 1480 and was wrong whenever the
# WAN fell back.
log " setup done -- run V0 to check the baseline"
}
# --- tests ------------------------------------------------------------------
V0() { # baseline
log "V0 baseline: the VIP holder owns the tunnel, the backup does not"
local h o; h="$(holder)"; o=$([ "$h" = "$R1" ] && echo "$R2" || echo "$R1")
[ "$h" = none ] && { fail "no VIP holder"; return; }
case "$(tun_state "$h")" in UP|UNKNOWN) pass "master $h has tun0 up" ;;
*) fail "master $h tun0 is $(tun_state "$h")" ;; esac
case "$(tun_state "$o")" in DOWN|absent) pass "backup $o tun0 is $(tun_state "$o")" ;;
*) fail "backup $o tun0 is $(tun_state "$o") -- it should be held down" ;; esac
v6_online "$h" && pass "master reaches HE over v6" || fail "master has no IPv6"
radvd_on "$h" && pass "master is advertising on VLAN 9" || fail "master radvd not running"
radvd_on "$o" && fail "backup is ALSO advertising -- two default routers on VLAN 9" \
|| pass "backup is not advertising"
check_invariants
save_evidence V0-baseline
}
V1() { # clean failover: v6 follows, and HE is never called
log "V1 clean failover: IPv6 follows, HE API untouched"
local from to t0 before after i
from="$(holder)"; to=$([ "$from" = "$R1" ] && echo "$R2" || echo "$R1")
before="$(he_calls)"
log " master=$from -> expecting $to (HE calls so far: ${before:-0})"
t0=$(date +%s)
r "$from" 'sudo mkdir -p /run/vrrp-wan && sudo touch /run/vrrp-wan/force-fault'
local took=""
for i in $(seq 1 36); do
sleep 5
[ "$(holder)" = "$to" ] && v6_online "$to" && { took=$(( $(date +%s) - t0 )); break; }
done
[ -n "$took" ] && pass "IPv6 reached $to in ${took}s" \
|| fail "IPv6 never followed to $to within 180s"
case "$(tun_state "$from")" in DOWN|absent) pass "$from released its tunnel" ;;
*) fail "$from still has tun0 $(tun_state "$from") -- blackhole risk" ;; esac
after="$(he_calls)"
# THE invariant this test exists for.
[ "${after:-0}" = "${before:-0}" ] \
&& pass "HE API not called (${after:-0} total) -- the address followed the MAC" \
|| fail "HE API called $(( ${after:-0} - ${before:-0} )) time(s) during a ROUTER failover"
check_invariants
save_evidence V1-clean-failover
r "$from" 'sudo rm -f /run/vrrp-wan/force-fault'
sleep 40
}
V2() { # 10 gig down on the master: HE must be told, exactly once
log "V2 10 gig down: he-tunnel-follow re-points the tunnel and tells HE"
local h before after mtu i ok=no
h="$(holder)"; before="$(he_calls)"
local tengig; tengig="$(tengig_addr)"
r "$h" 'sudo ip link set bond0.53 down'
# he-tunnel-follow runs on a 1m task-scheduler with a 2-tick hysteresis, so
# allow well past 2 minutes before calling it a failure.
for i in $(seq 1 30); do
sleep 10
[ "$(tun_src "$h")" != "$tengig" ] && { ok=yes; break; }
done
[ "$ok" = yes ] && pass "tunnel source moved to $(tun_src "$h") after $((i*10))s" \
|| fail "tunnel source never left the 10 gig address"
mtu="$(tun_mtu "$h")"
[ "$mtu" = 1472 ] && pass "MTU dropped to 1472 for the PPPoE path" \
|| fail "MTU is $mtu, want 1472 -- large transfers will hang"
after="$(he_calls)"
[ "$(( ${after:-0} - ${before:-0} ))" -ge 1 ] \
&& pass "HE API called $(( ${after:-0} - ${before:-0} )) time(s), as it must be here" \
|| fail "HE was never told -- it still points at an address this box no longer has"
v6_online "$h" && pass "IPv6 still up over PPPoE" || fail "IPv6 down on the PPPoE path"
save_evidence V2-tengig-down
r "$h" 'sudo ip link set bond0.53 up'
sleep 60
}
V3() { # a cold backup must not advertise, dial, or blackhole
log "V3 cold backup: no tunnel, no RA, no HE call"
local h o before after
h="$(holder)"; o=$([ "$h" = "$R1" ] && echo "$R2" || echo "$R1")
before="$(he_calls)"
r "$o" 'sudo systemctl restart vrrp-wan-reconcile.service' >/dev/null
sleep 20
case "$(tun_state "$o")" in DOWN|absent) pass "backup tunnel stays $(tun_state "$o")" ;;
*) fail "backup brought tun0 up while not holding the VIP" ;; esac
radvd_on "$o" && fail "backup is advertising on VLAN 9" || pass "backup is silent on VLAN 9"
after="$(he_calls)"
[ "${after:-0}" = "${before:-0}" ] && pass "backup made no HE call" \
|| fail "the BACKUP called the HE API -- it would point HE at its own idle line"
save_evidence V3-cold-backup
}
V4() { # the assumption the production override was built on
log "V4 a tunnel whose source-address is absent: what does VyOS actually do?"
# The production override says such a tunnel "would simply stay down", and
# treats that as the reason it was safe to leave IPv6 single-homed. Measured
# on the sim backup 2026-09-06: the commit SUCCEEDS and the link comes up
# anyway -- it is a blackhole, not an inert node. That is why the runtime
# gate is load-bearing rather than a nicety, exactly like the PPPoE gate.
local o h; h="$(holder)"; o=$([ "$h" = "$R1" ] && echo "$R2" || echo "$R1")
r "$o" 'sudo ip link set tun0 up' >/dev/null; sleep 3
case "$(tun_state "$o")" in
UP|UNKNOWN) pass "confirmed: VyOS leaves it UP with no source address (blackhole)" ;;
*) warn "this VyOS version keeps it $(tun_state "$o") -- the override's assumption holds here; re-check the production version before relying on it" ;;
esac
v6_online "$o" && fail "the backup somehow reached HE -- two live tunnels" \
|| pass "and it carries nothing, as expected"
# Hand it straight back to the reconciler rather than leaving it up.
r "$o" 'sudo systemctl restart vrrp-wan-reconcile.service' >/dev/null
sleep 15
case "$(tun_state "$o")" in DOWN|absent) pass "the reconciler put it back down" ;;
*) fail "the reconciler did NOT re-close the gate -- this is the load-bearing bit" ;; esac
save_evidence V4-absent-source-address
}
V5() { # never two live tunnels, even mid-transition
log "V5 both routers momentarily master: never two live tunnels"
local from to i worst=0 n
from="$(holder)"; to=$([ "$from" = "$R1" ] && echo "$R2" || echo "$R1")
r "$from" 'sudo mkdir -p /run/vrrp-wan && sudo touch /run/vrrp-wan/force-fault'
# Sample THROUGH the transition rather than at the ends. The interesting
# window is the one where both boxes briefly think they are in charge.
for i in $(seq 1 24); do
n="$(tun_holders)"; [ "${n:-0}" -gt "$worst" ] && worst="$n"
sleep 5
done
[ "$worst" -le 1 ] && pass "at most $worst live tunnel throughout the transition" \
|| fail "saw $worst live tunnels at once -- HE would receive two claimants"
r "$from" 'sudo rm -f /run/vrrp-wan/force-fault'
save_evidence V5-transition-invariant
sleep 40
}
V6() { # RA deprecation: does a VLAN 9 host drop the dead gateway?
log "V6 RA deprecation: the client must stop using a demoted router"
local h before
h="$(holder)"
before="$(lan9 'ip -6 route show default 2>/dev/null | head -1')"
if [ -z "$before" ]; then
warn "VLAN 9 client has no IPv6 default route -- SLAAC may not have run; skipping"
return
fi
log " client default was: $before"
r "$h" 'sudo mkdir -p /run/vrrp-wan && sudo touch /run/vrrp-wan/force-fault'
sleep 45
local after; after="$(lan9 'ip -6 route show default 2>/dev/null | head -1')"
log " client default now: ${after:-<none>}"
# radvd emits a final RA with router-lifetime 0 on a graceful stop. Either
# the client moved to the new master or it dropped the route entirely; both
# are correct. Still pointing at the demoted box is not.
if [ "$after" = "$before" ]; then
fail "client still points at the demoted router -- the farewell RA did not land"
else
pass "client stopped using the demoted router"
fi
r "$h" 'sudo rm -f /run/vrrp-wan/force-fault'
save_evidence V6-ra-deprecation
sleep 40
}
V7() { # replay the 2026-09-06 near-miss, but slowly
log "V7 slow WAN restore: does the hysteresis still hold?"
# On 2026-09-06 vif53-pin-boot-disable bounced the 10 gig, he-tunnel-follow
# ticked once and saw the PPPoE address, and vyos-failover restored the 10
# gig 22 SECONDS before the second tick would have pushed HE at an address
# Vodafone reissues on every dial. 22s of margin is not a safety property.
# Here the restore is deliberately slower than the hysteresis window.
local h before after tengig
h="$(holder)"; before="$(he_calls)"; tengig="$(tengig_addr)"
r "$h" 'sudo ip link set bond0.53 down'
sleep 200 # > 2 ticks of a 1m scheduler
r "$h" 'sudo ip link set bond0.53 up'
sleep 90
after="$(he_calls)"
if [ "$(( ${after:-0} - ${before:-0} ))" -ge 1 ]; then
warn "HE was updated $(( ${after:-0} - ${before:-0} )) time(s) and then had to move back -- this is the 2026-09-06 shape, now reproduced deliberately. Either widen HYSTERESIS or make vif53-pin-boot-disable hold he-tunnel-follow off for the bounce."
else
pass "no HE churn across a slow WAN bounce"
fi
# Whatever happened, the tunnel must end up back on the 10 gig.
local i
for i in $(seq 1 24); do
[ "$(tun_src "$h")" = "$tengig" ] && break
sleep 10
done
[ "$(tun_src "$h")" = "$tengig" ] && pass "tunnel returned to the 10 gig address" \
|| fail "tunnel stuck on $(tun_src "$h") after the 10 gig came back"
save_evidence V7-slow-restore
}
preflight() {
log "preflight"
local rc=0
[ "$(timeout 60 "$HE" status | grep -c 'API bound : nohost')" = 1 ] \
|| { fail "the fake HE endpoint is not answering -- run ./labsim-he-endpoint.sh up"; rc=1; }
local h
for h in "$R1" "$R2"; do
[ "$(tun_state "$h")" = absent ] \
&& { fail "$h has no tun0 -- run --setup first"; rc=1; }
[ "$(r "$h" 'systemctl is-active vrrp-wan-reconcile.timer')" = active ] \
|| { fail "$h vrrp-wan-reconcile.timer not active"; rc=1; }
# The reconciler must be the version that knows about the v6 plane, or
# every result below measures the OLD behaviour while printing the new
# test names -- the failure mode this repo has already been bitten by.
r "$h" 'grep -q v6_take /config/vrrp-wan-reconcile' \
|| { fail "$h has a vrrp-wan-reconcile with no IPv6 plane -- run migration/vrrp-wan-install"; rc=1; }
done
# Line the sim's endpoint up with whoever actually holds the tunnel. The real
# HE remembers where it was pointed; a rebuilt sim endpoint does not, and
# he-tunnel-follow will not re-assert because from its side nothing changed.
# Does NOT count as an API call, so the invariant-2 assertions stay honest.
local m src
m="$(holder)"; src="$(tun_src "$m")"
if [ -n "$src" ]; then
timeout 60 "$HE" point "$src" >/dev/null 2>&1 \
|| { fail "could not point the sim HE endpoint at $src"; rc=1; }
fi
[ "$rc" -eq 0 ] && pass "HE endpoint answering and pointed at $src, both routers have tun0 and a v6-aware reconciler"
return $rc
}
case "${1:---all}" in
--list) echo "V0 baseline | V1 clean failover | V2 10gig-down | V3 cold backup | V4 absent source-address | V5 transition invariant | V6 RA deprecation | V7 slow restore"; exit 0 ;;
--setup) setup; exit 0 ;;
--all) preflight || exit 1; V0; V1; V2; V3; V4; V5; V6; V7 ;;
*) preflight || exit 1; "$1" ;;
esac
echo
[ "$FAILED" -eq 0 ] && { echo "ALL PASS"; exit 0; }
echo "$FAILED check(s) FAILED"; exit 1