Move pure resolver logic out of anycast_linux.go into anycast.go so it's
unit-testable on any host. Reshape anycastTarget from a single
{hostIface, via} into a sorted list of nexthops; multiple Ready pods on
the same node binding the same anycast IP now contribute one nexthop
each.
installAnycastRoute uses RTA_MULTIPATH (via netlink.Route.MultiPath)
when the target has more than one nexthop. Single-nexthop targets keep
the simple via-route shape so 1-pod-per-node keeps rendering identically
to today's production form in `ip route show`.
flock-agent writes net.ipv{4,6}.fib_multipath_hash_policy = 1 at
startup so the kernel hashes flows on (saddr, daddr, sport, dport, proto)
rather than just IPs. Best-effort — runs privileged in production, so
it works; falls back to L3 hash on environments where the write fails
(only matters for the multi-pod-per-node case anyway).
resolveAnycastTargets sorts nexthops by canonical(via) for stable
comparison so a quiet reconcile pass doesn't churn the kernel route.
8 new unit tests cover: 1-pod, 2-pods-same-anycast (multi-nexthop),
NotReady drop, no-Ready omits the IP, pending skipped, mixed v6+v4,
family mismatch warns, determinism.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
New pkg/agent/netpol implementing standard networking.k8s.io/v1
NetworkPolicy. Pipeline:
pods + policies + namespaces → Translate → Render → Apply
Supports ingress + egress, all three peer types (podSelector,
namespaceSelector, ipBlock with except), numeric ports + port ranges,
default-deny semantics derived from PolicyTypes (or inferred from
non-empty Spec.Egress when unset).
Apply path is `nft -f -` shell-out — single transaction, atomic, kernel
guarantees partial-failure rollback. Idempotent dedup via last-applied
script. Reconcile triggers: informer events, 30s self-heal tick, every
CNI ADD/DEL.
Verified against the three live cluster NetPols (calico-apiserver,
remote-proxies/lodge-home-assistant, storage/garage-admin-restrict).
Fuzz target stitches Translate + Render with random selector and peer
inputs; 21 unit tests cover the policy semantics.
Named ports skip with a warn — deferred until kubelet exposes them in a
form that doesn't require shadowing pod state.
Dockerfile: + nftables.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
CNI ADD now adds anycast IPs to the pod's lo interface (NOT eth0 — design
doc rationale: avoid NDP/ARP DAD conflicts when N replicas share an IP).
Allocation persists the anycast list.
AnycastReconciler:
desired = { ip → flock<8hex> } from
committed allocations × pod.Status.PodReady=True
diff against advertised, install/remove host /128 (v6) or /32 (v4)
re-render bird.conf with the active set
Triggers: 2s tick, AfterCommit (per ADD/DEL), Pod informer Ready
transitions (PodCache.OnReadyChange callback).
The bird template already supported Anycast6/Anycast4 via the export
filter — this turn finally drives those slices from runtime.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
When Calico shuts down on a flock-labeled node, calico-node sets
NetworkUnavailable=True with reason CalicoIsDown. Nothing replaces it,
so kubelet's NodeController applies node.kubernetes.io/network-
unavailable:NoSchedule and new pods can't land.
flock-agent now patches Status.Conditions every 60s with
NetworkUnavailable=False (reason=FlockReady). RBAC: nodes/status patch.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
Calico fenced off via Tigera Installation CR (apps@2121892). flock-agent
now renders bird.conf with the per-node BGP peers; bird sidecar reloads
on changes (debounced 500ms). Re-render tick every 15s reacts to
NodeConfig updates.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
Calico's calico-node still runs on every node (Tigera-Operator-managed
via ArgoCD with selfHeal). Two birds with the same ASN can't peer to
crt001 from the same source. Use a manual static route on crt001 for
the flock /64 for the first cutover; switch to live BGP after Calico is
fenced off flock-labeled nodes.
The bird sidecar stays running with the bootstrap config (kernel +
device only, no BGP), so flipping live BGP on later is a single-line
change in runtime_linux.go.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
Donavan Fritz