d8b25a67feeea46f3e1311d4e8fb15aedaaad8e8
5
Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
  jakman85andClaude Opus 5
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37a6c94168 |
fix(vpn): two gateways on one pinned PIA server evict each other every 2 minutes
Standing up prod broke dev, and the mechanism is worth spelling out because
"same PIA account, well inside its connection limit" is true and still not enough.
The vaulted .ovpn pins ONE server. With both gateways using it, dev and prod
landed on the SAME server AND were handed the SAME tunnel address — both journals
read `[Server-10779-2a] Peer Connection Initiated with [AF_INET]158.173.241.112:1198`
and `ifconfig 10.72.192.7 255.255.192.0`. Each reconnect steals that address on
that server; the loser then receives nothing, trips `--ping-restart` after 60s,
reconnects and steals it back. Measured cycle: dev restarting at 22:57:05,
22:59:03, 23:01:05 UTC with prod interleaved about a minute off, each ~2 minutes
apart, indefinitely. Neither environment had reliable vpn-class egress — prod's
probes looked green only because they happened to land inside an up-window.
Fix: `vpn_egress_gateway_pia_remote` ("<host> <port>", empty = honour the .ovpn)
rewrites just the `remote` line of the deployed .ovpn, and prod's group_vars sets
it to 158.173.241.135. That is another member of the same PIA Stockholm LB pool —
`sweden.privacy.network` resolved from k3s-prod-3 to
158.173.241.{34,55,112,135,239} — and every server in the pool takes the same
credentials and the same inline CA, so only the address differs. Dev keeps the
.ovpn's .112 untouched, which is why the override is per-group rather than in the
role or a second vaulted .ovpn.
Two details that matter for whoever touches this next:
* The regex is anchored to a line STARTING with `remote` plus whitespace, so
`remote-cert-tls` and `remote-random` are not collateral damage. The task keeps
`no_log: true` — the transformation never widens what is logged.
* A PIA server address is NOT a credential, so it lives in
group_vars/vpn_egress_gateway_prod/vars.yml in the clear, next to the vault
rather than inside it. Keeping it out of the vault is what makes it reviewable.
If prod ever gets its own PIA account, this override can be deleted again.
Co-Authored-By: Claude Opus 5 <[email protected]>
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jakman85andClaude Opus 5
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04606d48b2 |
docs(vpn): stop crediting the nftables kill-switch for a drop it never makes
Four places in the tree told the reader that the host nftables table is the authoritative fail-closed backstop for egress-class=vpn pods: platform/vpn-egress README, egress-steering.yaml, the role README, and the vpn-killswitch test's own GIVEN/THEN prose. It is not, and cannot be — Cilium's eBPF egress-gateway datapath bpf_redirect()s those skbs to the egress device without invoking netfilter POSTROUTING. Corrected with the measurement in each place rather than softened, because a guard the repo trusts and that does not fire is worse than no guard. What replaces the claim, everywhere: vpn-class fails closed because CILIUM drops the traffic when it cannot use its cached egress interface, verified by tcpdump on both the WAN and tun0 during a tunnel stop and a tunnel restart (0 packets out either). The nft table keeps a narrower, now-proven job: node-originated traffic sourced from a tunnel address (killswitch_drop moved 0 -> 3 packets on k3s-prod-3 when such a packet was routed at the WAN). Also recorded: * egress-steering.yaml — `interface: tun0` is resolved ONCE and cached, and the gateway node is what tells Cilium it changed (the egress-uplink node label). A future reader's instinct will be to have the node write to that object; the comment says not to, because it is Flux-managed, and points at the label and `cilium-dbg bpf egress list` as the debugging entry points instead. * egress-steering.yaml — why the new NFS media mounts are not affected by pod-scoped steering: an NFS PV is mounted by the node kernel in the host netns, so podSelector never matches it. The 192.168.0.0/16 exclusion covers the server too, but that is the second reason, not the first. * vpn-killswitch test — its recovery step depends on the re-steer path, and could not have passed before it existed. Its no-leak assertion was always right; only the explanation was wrong. Also states the prerequisite plainly: the test cannot run at all without a labelled gateway node. * platform README — prod is live on k3s-prod-3 with the before/after egress IPs, and the note that prod's vpn-class pods had NO internet beforehand (CEGP with no matching node -> `Gateway IP: Not Found` -> dropped), so arming the gateway restored egress rather than moving it off the WAN. * role README — the standing "add the shared fwmark to the interface contract" escalation is closed as not implementable on Cilium OSS, rather than left open for someone to attempt. DECISIONS-LOG carries the full session entry, including the drafted ADR-0015 / docs-03 amendment for the architect (specs are immutable to agents) and the five things left for the operator — chief among them that a silent gateway outage still has no alert, which is what let the dev gateway sit dead for 80 minutes. Co-Authored-By: Claude Opus 5 <[email protected]> |
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jakman85andClaude Opus 5
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6f698f59af |
fix(vpn): Cilium never re-resolves tun0 — the gateway dies on every reconnect
Measured on k3s-dev-3, not reasoned about. Three findings, one of which had the dev gateway silently dead for ~80 minutes before this change: 1. Cilium caches (egress IP, egress ifindex) when it first resolves the CEGP's `interface: tun0` and does NOT re-resolve when tun0 changes. Every tunnel restart re-creates tun0 with a NEW ifindex, so vpn-class egress is blackholed from then on. Observed: node had tun0 at ifindex 1987 while `cilium-dbg bpf egress list` still said 1986; pod curl timed out. Forcing a re-apply moved the map to 1987 and egress recovered instantly. `egress-gateway-reconciliation- trigger-interval: 1s` does NOT cover netlink link events — dev has that same 1s setting and still did not self-heal, 20s+ after recovery. Fix: vpn-egress-resteer.sh publishes "<tun0 addr>-<ifindex>" as a node label. A node update makes the gateway re-process the policy (verified: cached ifindex 1986 -> 1987 within 10s). A node label, not an annotation on the policy, because the policy is Flux-managed GitOps and the node's labels are already this role's territory. Fired by the OpenVPN up-script on every connect, plus a 2-minute convergence timer for the boot case where the kube-API is not up yet. Proof: `systemctl stop` then `start` of the tunnel now recovers on its own (map 1989 -> 1990, PIA IP returns); before this commit the identical sequence stayed broken indefinitely. 2. The nft kill-switch CANNOT see the traffic it claims to guard. A counters-only diagnostic table on the gateway node recorded, while a vpn-class pod egressed: 0 packets in forward and 0 in postrouting for both the pod CIDR and the PIA range, against 45166 packets on the same postrouting hook for WAN traffic and 16 packets for a node-originated curl out tun0. Cilium's eBPF datapath bpf_redirect()s these skbs to the egress device without invoking netfilter. So `ip saddr @set oifname != tun0 drop` can never fire for vpn-class pods. What actually fails closed is Cilium's own drop when the cached egress interface is unusable — tcpdump during a tunnel stop AND during a restart showed 0 packets leaving either the WAN or tun0. Every rule now carries a `counter` so the claim stays falsifiable, and every comment that called this table the authoritative vpn-class backstop is corrected rather than left to mislead the next reader. Also removed the `meta mark 0x1c8 oifname != tun0 drop` rule and its variable: nothing stamps that mark (the only Cilium mark on the node is 0x200/0xf00, the L7-proxy rule to table 2004), the traffic never reaches netfilter anyway, and a live rule matching an arbitrary mark is a hazard to whatever picks it next. 3. The up-script flushed the nft source set on every connect, so a packet still sourced from the previous tunnel address matched neither the ip-rule nor the drop rule. The set is now additive (`add element` is idempotent; the down-script already retained it): an element can only ever tighten the guard. Finding 2 means that window could not have leaked POD traffic, but node-originated tunnel traffic does traverse netfilter, and additive is free. Kill-switch reloads no longer disarm the guard either: the .nft file uses `table` + `flush table`, which clears rules but leaves the named set's elements intact, so an Ansible run cannot empty the set mid-flight. Co-Authored-By: Claude Opus 5 <[email protected]> |
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jakman85andClaude Opus 4.8
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1c4d86319c |
vpn_egress_gateway: retain nft src set on tunnel-down (explicit fail-closed backstop)
The down-script previously flushed the kill-switch source set on tunnel-down, which disarmed the 'ip saddr @vpn_egress_gateway_src oifname != tun0 drop' rule exactly when the tunnel was down — leaving fail-closed to ride only on the stale SNAT source being non-routable (could leak if the edge NATed it). Retain the set instead: the drop rule stays armed so any vpn-class packet leaving the WAN while the tunnel is down is EXPLICITLY dropped (edge-independent). Safe because the up-script flush+re-adds the source on every reconnect. Validated behavior: WS-NET fault-injection on k3s-dev-3 (2026-08-24). Co-Authored-By: Claude Opus 4.8 <[email protected]> |
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jakman85andClaude Opus 4.8
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2c109e2a31 |
feat(vpn): node-level split-tunnel egress gateway Ansible role (ADR-0015)
Author the vpn_egress_gateway role + playbook that stands up the NODE-level PIA OpenVPN tunnel on egress-gateway node(s) — the host half of ADR-0015. The CiliumEgressGatewayPolicy steering vpn-class pods is separate GitOps against the same contract (group vpn_egress_gateway, node label homelab.keithjackson.dev/egress-gateway=true, host iface tun0). Honors all four ADR-0015 invariants: - Split-tunnel (inv 1&2): OpenVPN route-noexec + pull-filter ignore redirect-gateway => installs no routes; policy routing in a dedicated table (51820) with `ip rule from <tun0-addr>` steers ONLY Cilium-SNAT'd vpn-class traffic. Node default route stays on the WAN, tunnel up or down. - Scoped nftables kill-switch (inv 3&4): own inet table, policy accept, drops only tunnel-sourced (@vpn_egress_gateway_src set) packets not leaving tun0 => vpn-class fails closed (blackhole), node/internet-class fail open (WAN), never matched. PIA creds + the proven sweden-aes-128-cbc-udp-ip .ovpn come from Ansible vault (host-side per ADR-0015/docs-07); vault keys documented, no secret values committed. ansible-lint (production) + yamllint clean. Not deployed: green conformance is gated on the live tunnel (operator host creds) — see role README. Co-Authored-By: Claude Opus 4.8 <[email protected]> |