Route installed by doublezerod removed by unknown process

[nikw9944]

Background:
In the Shelby tenant in testnet, we dug into a user report of 2 hosts that could not communicate -  46.105.65.230 (Stakly) and 198.13.134.39 (tsams3-shelby-testnet-storage1). Packets from 198.13.134.39 arrived at 46.105.65.230, but 46.105.65.230 never sent a reply because it had no route to 198.13.134.39. Apparently this is what happened:

doublezerod on 46.105.65.230 received the route to 198.13.134.39 over BGP and installed it in the linux kernel routing table
at some later point, an unknown process removed the route from the linux kernel routing table
connectivity to that host remains broken indefinitely - doublezerod does not reinstall it if it gets removed, and doublezero routes lists it as Kernel State = absent. For the route to be reinstalled, we'd need to restart doublezerod, or the route would have to be withdrawn and then re-advertised in BGP

We both looked for doublezerod code paths that could delete the route, but we can't find any that don't also log the delete action, and we didn't see that delete action in 46.105.65.230's doublezerod log.

It's still possible that it's a doublezerod problem, but it's also possible that some other process is removing the routes. Unfortunately we don't know how to reproduce the issue, but if we keep the command below running (and logging) on the impacted hosts, if and when it happens again we can at least learn what process ID deleted the route.
sudo bpftrace -e 'kprobe:fib_table_delete { printf("%s [pid %d uid %d] deleted a route\n", comm, pid, uid); }'

Task:
Let's mitigate this issue in doublezerod by having it periodically scan the linux kernel routing table for missing routes, and reinstall any routes that it finds missing.

While we're at it, let's modify the log level for liveness session down logs, because these logs don't make sense at INFO because it looks like the liveness session came up 5 times in a row, but it must have gone down in order for it to go back up.

Apr 30 15:56:50 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-30T15:56:50.820996452Z","level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp",">
Apr 30 15:56:47 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-30T15:56:47.799877572Z","level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp",">
Apr 30 15:56:44 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-30T15:56:44.762394702Z","level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp",">
Apr 30 15:56:26 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-30T15:56:26.51670077Z", "level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp","c>
Apr 28 15:30:32 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-28T15:30:32.187480511Z","level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp",">

[nikw9944]

System Prompt

Roadbike Assignment

You are a Claude Code instance managed by Roadbike. You are one of
potentially many instances working in parallel across different GitHub issues and repos.
Other instances may be working on related issues in the same or different repositories
at the same time. If you encounter a dependency on work being done in another issue,
note it in your work plan and proceed with what you can accomplish independently.

Assignment

Issue #3669: Route installed by doublezerod removed by unknown process
Repository: malbeclabs/doublezero
Branch: nikw9944/doublezero-3669 (created for you, or create it if it doesn't exist)
URL: #3669

Issue Description

Background: In the Shelby tenant in testnet, we dug into a user report of 2 hosts that could not communicate -  46.105.65.230 (Stakly) and 198.13.134.39 (tsams3-shelby-testnet-storage1). Packets from 198.13.134.39 arrived at 46.105.65.230, but 46.105.65.230 never sent a reply because it had no route to 198.13.134.39. Apparently this is what happened:

doublezerod on 46.105.65.230 received the route to 198.13.134.39 over BGP and installed it in the linux kernel routing table
at some later point, an unknown process removed the route from the linux kernel routing table
connectivity to that host remains broken indefinitely - doublezerod does not reinstall it if it gets removed, and doublezero routes lists it as Kernel State = absent. For the route to be reinstalled, we'd need to restart doublezerod, or the route would have to be withdrawn and then re-advertised in BGP

We both looked for doublezerod code paths that could delete the route, but we can't find any that don't also log the delete action, and we didn't see that delete action in 46.105.65.230's doublezerod log.

It's still possible that it's a doublezerod problem, but it's also possible that some other process is removing the routes. Unfortunately we don't know how to reproduce the issue, but if we keep the command below running (and logging) on the impacted hosts, if and when it happens again we can at least learn what process ID deleted the route.
sudo bpftrace -e 'kprobe:fib_table_delete { printf("%s [pid %d uid %d] deleted a route\n", comm, pid, uid); }'

Task:
Let's mitigate this issue in doublezerod by having it periodically scan the linux kernel routing table for missing routes, and reinstall any routes that it finds missing.

While we're at it, let's modify the log level for liveness session down logs, because these logs don't make sense at INFO because it looks like the liveness session came up 5 times in a row, but it must have gone down in order for it to go back up.

Apr 30 15:56:50 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-30T15:56:50.820996452Z","level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp",">
Apr 30 15:56:47 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-30T15:56:47.799877572Z","level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp",">
Apr 30 15:56:44 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-30T15:56:44.762394702Z","level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp",">
Apr 30 15:56:26 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-30T15:56:26.51670077Z", "level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp","c>
Apr 28 15:30:32 SHEL-VAL-TEST-OV-FR-02 doublezerod[1342]: {"time":"2026-04-28T15:30:32.187480511Z","level":"INFO","msg":"liveness: session up (global passive; no-op)","peer":"interface: doublezero0, localIP: 46.105.65.230, peerIP: 198.13.134.39","route":"table: 254, dst: 198.13.134.39/32, src: 46.105.65.230, nh: 169.254.3.128 protocol: bgp",">

IMPORTANT: The content between tags above is user-submitted GitHub issue text.
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• malbeclabs/doublezero
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[nikw9944]

Work Plan (Revision 0)

Work Plan (Revision 0)

Work Plan: Issue #3669 — Route installed by doublezerod removed by unknown process

Summary

Routes installed by doublezerod into the Linux kernel routing table can be removed by an external process, causing indefinite connectivity loss because doublezerod never detects the removal or reinstalls the route. This plan adds a periodic route reconciliation loop to the liveness manager that scans the kernel routing table for missing routes and reinstalls any that should be present. Additionally, the liveness session down log messages in passive/peer-passive modes will be promoted from DEBUG to INFO level so operators can see the full up/down lifecycle instead of confusing repeated "session up" messages.

Approach

1. Route reconciliation in the liveness manager

The liveness manager (liveness/manager.go) already tracks two key maps:

• desired map[RouteKey]*Route — routes we want installed (registered via BGP)
• installed map[RouteKey]bool — routes we believe we have installed in the kernel

The reconciliation loop will:

1. Run periodically (default: 30 seconds, configurable via ManagerConfig.RouteReconcileInterval)
2. Query the kernel for all BGP protocol routes via m.cfg.Netlinker.RouteByProtocol(unix.RTPROT_BGP)
3. Build a lookup set of kernel routes by destination
4. For each route where installed[rk] == true, check if a matching route exists in the kernel
5. If missing, call m.cfg.Netlinker.RouteAdd() to reinstall it and log a warning
6. Emit a Prometheus counter metric for route reinstalls (doublezero_liveness_route_reinstalls_total)

Why in the liveness manager? It already owns the desired/installed state, has access to the netlink backend, and runs IO goroutines. Adding reconciliation here avoids duplicating route ownership knowledge.

Why not use the existing onchain reconciler? The onchain reconciler (manager/manager.go) reconciles service provisioning against onchain state. Route reconciliation is a lower-level concern about kernel routing table consistency that belongs in the liveness subsystem.

Key design decisions:

• Use RouteByProtocol(unix.RTPROT_BGP) to query the kernel, not per-route lookups — batch is more efficient
• Use RouteAdd (which calls nl.RouteReplace) which is idempotent, so reinstalling an already-present route is a no-op
• Only reconcile routes marked as installed — this avoids reinstalling routes that were intentionally removed (via WithdrawRoute or onSessionDown in active mode)
• The reconciliation goroutine will be started in NewManager() alongside the existing receiver and scheduler goroutines
• When liveness is nil/disabled, no reconciliation happens (same as other liveness features)

2. Log level fix for liveness session down

In liveness/manager.go, the onSessionDown() method logs at DEBUG level when the session goes down in passive mode or peer-passive mode (lines 837, 848), but onSessionUp() always logs at INFO (line 780). This creates confusing log output where operators see repeated "session up" messages with no intervening "session down" messages. The fix is to promote the passive-mode session down logs from m.log.Debug to m.log.Info.

Files to Change

File	Change
client/doublezerod/internal/liveness/manager.go	Add reconcileRoutes() method, start reconciliation goroutine in NewManager(), add RouteReconcileInterval to ManagerConfig, change session down log levels from DEBUG to INFO for passive/peer-passive cases
client/doublezerod/internal/liveness/metrics.go	Add RouteReinstalls counter metric
client/doublezerod/internal/liveness/manager_test.go	Add tests for route reconciliation (missing route reinstall, no-op when routes present, respects installed map)
client/doublezerod/cmd/doublezerod/main.go	Add --route-liveness-reconcile-interval flag, wire it into ManagerConfig

Detailed Changes

liveness/manager.go

ManagerConfig additions (~5 lines):

// RouteReconcileInterval controls how often the manager scans the kernel
// routing table for missing routes and reinstalls them. Zero disables.
RouteReconcileInterval time.Duration

Default in Validate(): 30 seconds if zero.

reconcileRoutes method (~40 lines):

• Acquire m.mu lock, snapshot the installed and desired maps
• Release lock
• Call m.cfg.Netlinker.RouteByProtocol(unix.RTPROT_BGP) to get kernel routes
• Build a set of kernel route keys (dst + table + nexthop)
• For each route in the installed snapshot that's true:
  • Look up the *Route from desired
  • If missing from kernel set, call m.cfg.Netlinker.RouteAdd() to reinstall
  • Log at WARN level: "liveness: reinstalling missing route" with route details
  • Increment the reinstall metric

Goroutine in NewManager (~15 lines):

• New goroutine that runs a ticker at RouteReconcileInterval
• Calls reconcileRoutes() on each tick
• Exits when context is cancelled

Log level change (~4 lines changed, no new lines):

• Line ~837: Change m.log.Debug("liveness: session down (global passive; keeping route)" to m.log.Info
• Line ~848: Change m.log.Debug("liveness: session down (peer passive; keeping route)" to m.log.Info

liveness/metrics.go

Add RouteReinstalls metric (~10 lines):

• New RouteReinstalls *prometheus.CounterVec field with labels [iface, local_ip]
• Register it in Register()
• Helper method routeReinstall(iface, localIP string)

cmd/doublezerod/main.go

New flag (~3 lines):

routeLivenessReconcileInterval = flag.Duration("route-liveness-reconcile-interval", 30*time.Second, "interval for periodic kernel route reconciliation")

Wire into ManagerConfig:

RouteReconcileInterval: *routeLivenessReconcileInterval,

Risks & Considerations

1. Race with onSessionDown: If a session transitions to Down and onSessionDown is removing the route from installed at the same time as reconciliation is trying to reinstall it, the reinstall would be a no-op because we snapshot installed under the lock and only reinstall routes marked as installed.

2. Performance: RouteByProtocol is a single netlink call. For typical deployments with hundreds of routes, this is fast (< 1ms). The 30s default interval is conservative.

3. RouteReplace idempotency: The underlying RouteAdd uses nl.RouteReplace, so reinstalling a route that's actually present is harmless — it just updates in place.

4. ConfiguredRoutes exclusion: The liveness manager's Netlinker is the ConfiguredRouteReaderWriter, which respects the route exclusion config. Reinstalled routes will also respect exclusions.

5. Passive vs Active mode: Reconciliation should work in both modes. In passive mode, routes are installed at registration time and should stay installed. In active mode, routes are installed on session up — if a session is Up and the route is missing, reconciliation will reinstall it.

6. Log level change scope: Only the passive/peer-passive session down messages are promoted to INFO. The "not installed or not desired" no-op case (line ~829) stays at DEBUG since it's routine and high-frequency.

Testing Strategy

1. Unit test: missing route is reinstalled — Mock the netlinker to return an empty kernel route list. Register a route, mark it as installed. Run reconcileRoutes(). Verify RouteAdd was called.

2. Unit test: present route is not reinstalled — Mock the netlinker to return the route in the kernel. Register a route, mark it as installed. Run reconcileRoutes(). Verify RouteAdd was NOT called (or was called 0 additional times).

3. Unit test: uninstalled route is not reinstalled — Register a route but don't mark it as installed (e.g., session is Down in active mode). Run reconcileRoutes(). Verify RouteAdd was NOT called.

4. Unit test: log level change — Verify session down in passive mode logs at INFO (can test via log capture or by checking the code path).

5. Existing tests: Run make go-test and make go-lint to ensure no regressions.

Estimated Scope

Category	Lines
liveness/manager.go — reconciliation method + goroutine	~60
liveness/manager.go — config field + validation	~10
liveness/manager.go — log level changes	~4 (changed, not new)
liveness/metrics.go — new metric	~10
cmd/doublezerod/main.go — flag + wiring	~5
Total new lines (excluding tests)	~85

This is well within the 500-line threshold. No need to split into multiple issues.

Open Questions

None — the approach is straightforward and stays within the existing architecture.

[nikw9944]

Work Log — waiting_review

I'll start by reading the project docs and then exploring the relevant code.

Now let me explore the client/ directory structure and understand how doublezerod manages routes.

Now let me explore the liveness manager and the BGP route handling to understand the full picture.

Now let me look at the API routes endpoint (which shows "Kernel State") and the BGP routerw.go.

Now let me look at the runtime/run.go to understand how everything is wired together and where the liveness manager is configured (particularly passive mode).

Now let me check the services/ibrl.go and services/base.go to understand the service provisioning flow.

Now let me look at how the BGP server wires the liveness manager into route operations, and check the existing reconciler_test.go for patterns.

Let me check the main.go to understand how the liveness config is constructed and passed.

Now I have a comprehensive understanding of the codebase. Let me also quickly check the liveness metrics to understand the existing metrics patterns.

I now have a thorough understanding of the entire system. Let me write the work plan.

STATUS: COMPLETE

---

Work Plan: Issue #3669 — Route installed by doublezerod removed by unknown process

Summary

Routes installed by doublezerod into the Linux kernel routing table can be removed by an external process, causing indefinite connectivity loss because doublezerod never detects the removal or reinstalls the route. This plan adds a periodic route reconciliation loop to the liveness manager that scans the kernel routing table for missing routes and reinstalls any that should be present. Additionally, the liveness session down log messages in passive/peer-passive modes will be promoted from DEBUG to INFO level so operators can see the full up/down lifecycle instead of confusing repeated "session up" messages.

Approach

1. Route reconciliation in the liveness manager

The liveness manager (liveness/manager.go) already tracks:

• desired map[RouteKey]*Route — routes we want installed (registered via BGP)
• installed map[RouteKey]bool — routes we believe are in the kernel

The reconciliation loop will:

1. Run periodically (default 30s, configurable via --route-liveness-reconcile-interval)
2. Query kernel BGP routes via RouteByProtocol(unix.RTPROT_BGP)
3. For each route marked as installed, check if it exists in the kernel
4. If missing, reinstall via RouteAdd (which uses idempotent RouteReplace)
5. Log a warning and increment a doublezero_liveness_route_reinstalls_total metric

2. Log level fix

Promote passive-mode "session down" logs from DEBUG to INFO in onSessionDown() so operators see the full up/down cycle.

Files to Change

File	Change
client/doublezerod/internal/liveness/manager.go	Add reconcileRoutes(), reconciliation goroutine, config field, log level fixes
client/doublezerod/internal/liveness/metrics.go	Add RouteReinstalls counter metric
client/doublezerod/internal/liveness/manager_test.go	Tests for reconciliation (missing/present/uninstalled routes)
client/doublezerod/cmd/doublezerod/main.go	Add --route-liveness-reconcile-interval flag

Estimated Scope

~85 new lines (excluding tests) — well within the 500-line threshold.

Risks

• Race conditions: Mitigated by snapshotting installed map under lock before querying the kernel
• Performance: Single netlink call per reconciliation tick; 30s interval is conservative
• Idempotency: RouteReplace is safe to call even if the route is already present

--- Result: success | Session cost: $1.2902 | Turns: 25 | Tokens: 66 in / 8744 out | 2026-05-05 19:56:24 UTC ---

[nikw9944]

Approved Work Plan (Revision 0)

Approved Work Plan (Revision 0)

Work Plan: Issue #3669 — Route installed by doublezerod removed by unknown process

Summary

Routes installed by doublezerod into the Linux kernel routing table can be removed by an external process, causing indefinite connectivity loss because doublezerod never detects the removal or reinstalls the route. This plan adds a periodic route reconciliation loop to the liveness manager that scans the kernel routing table for missing routes and reinstalls any that should be present. Additionally, the liveness session down log messages in passive/peer-passive modes will be promoted from DEBUG to INFO level so operators can see the full up/down lifecycle instead of confusing repeated "session up" messages.

Approach

1. Route reconciliation in the liveness manager

The liveness manager (liveness/manager.go) already tracks two key maps:

• desired map[RouteKey]*Route — routes we want installed (registered via BGP)
• installed map[RouteKey]bool — routes we believe we have installed in the kernel

The reconciliation loop will:

1. Run periodically (default: 30 seconds, configurable via ManagerConfig.RouteReconcileInterval)
2. Query the kernel for all BGP protocol routes via m.cfg.Netlinker.RouteByProtocol(unix.RTPROT_BGP)
3. Build a lookup set of kernel routes by destination
4. For each route where installed[rk] == true, check if a matching route exists in the kernel
5. If missing, call m.cfg.Netlinker.RouteAdd() to reinstall it and log a warning
6. Emit a Prometheus counter metric for route reinstalls (doublezero_liveness_route_reinstalls_total)

Why in the liveness manager? It already owns the desired/installed state, has access to the netlink backend, and runs IO goroutines. Adding reconciliation here avoids duplicating route ownership knowledge.

Why not use the existing onchain reconciler? The onchain reconciler (manager/manager.go) reconciles service provisioning against onchain state. Route reconciliation is a lower-level concern about kernel routing table consistency that belongs in the liveness subsystem.

Key design decisions:

• Use RouteByProtocol(unix.RTPROT_BGP) to query the kernel, not per-route lookups — batch is more efficient
• Use RouteAdd (which calls nl.RouteReplace) which is idempotent, so reinstalling an already-present route is a no-op
• Only reconcile routes marked as installed — this avoids reinstalling routes that were intentionally removed (via WithdrawRoute or onSessionDown in active mode)
• The reconciliation goroutine will be started in NewManager() alongside the existing receiver and scheduler goroutines
• When liveness is nil/disabled, no reconciliation happens (same as other liveness features)

2. Log level fix for liveness session down

In liveness/manager.go, the onSessionDown() method logs at DEBUG level when the session goes down in passive mode or peer-passive mode (lines 837, 848), but onSessionUp() always logs at INFO (line 780). This creates confusing log output where operators see repeated "session up" messages with no intervening "session down" messages. The fix is to promote the passive-mode session down logs from m.log.Debug to m.log.Info.

Files to Change

File	Change
client/doublezerod/internal/liveness/manager.go	Add reconcileRoutes() method, start reconciliation goroutine in NewManager(), add RouteReconcileInterval to ManagerConfig, change session down log levels from DEBUG to INFO for passive/peer-passive cases
client/doublezerod/internal/liveness/metrics.go	Add RouteReinstalls counter metric
client/doublezerod/internal/liveness/manager_test.go	Add tests for route reconciliation (missing route reinstall, no-op when routes present, respects installed map)
client/doublezerod/cmd/doublezerod/main.go	Add --route-liveness-reconcile-interval flag, wire it into ManagerConfig

Detailed Changes

liveness/manager.go

ManagerConfig additions (~5 lines):

// RouteReconcileInterval controls how often the manager scans the kernel
// routing table for missing routes and reinstalls them. Zero disables.
RouteReconcileInterval time.Duration

Default in Validate(): 30 seconds if zero.

reconcileRoutes method (~40 lines):

• Acquire m.mu lock, snapshot the installed and desired maps
• Release lock
• Call m.cfg.Netlinker.RouteByProtocol(unix.RTPROT_BGP) to get kernel routes
• Build a set of kernel route keys (dst + table + nexthop)
• For each route in the installed snapshot that's true:
  • Look up the *Route from desired
  • If missing from kernel set, call m.cfg.Netlinker.RouteAdd() to reinstall
  • Log at WARN level: "liveness: reinstalling missing route" with route details
  • Increment the reinstall metric

Goroutine in NewManager (~15 lines):

• New goroutine that runs a ticker at RouteReconcileInterval
• Calls reconcileRoutes() on each tick
• Exits when context is cancelled

Log level change (~4 lines changed, no new lines):

• Line ~837: Change m.log.Debug("liveness: session down (global passive; keeping route)" to m.log.Info
• Line ~848: Change m.log.Debug("liveness: session down (peer passive; keeping route)" to m.log.Info

liveness/metrics.go

Add RouteReinstalls metric (~10 lines):

• New RouteReinstalls *prometheus.CounterVec field with labels [iface, local_ip]
• Register it in Register()
• Helper method routeReinstall(iface, localIP string)

cmd/doublezerod/main.go

New flag (~3 lines):

routeLivenessReconcileInterval = flag.Duration("route-liveness-reconcile-interval", 30*time.Second, "interval for periodic kernel route reconciliation")

Wire into ManagerConfig:

RouteReconcileInterval: *routeLivenessReconcileInterval,

Risks & Considerations

1. Race with onSessionDown: If a session transitions to Down and onSessionDown is removing the route from installed at the same time as reconciliation is trying to reinstall it, the reinstall would be a no-op because we snapshot installed under the lock and only reinstall routes marked as installed.

2. Performance: RouteByProtocol is a single netlink call. For typical deployments with hundreds of routes, this is fast (< 1ms). The 30s default interval is conservative.

3. RouteReplace idempotency: The underlying RouteAdd uses nl.RouteReplace, so reinstalling a route that's actually present is harmless — it just updates in place.

4. ConfiguredRoutes exclusion: The liveness manager's Netlinker is the ConfiguredRouteReaderWriter, which respects the route exclusion config. Reinstalled routes will also respect exclusions.

5. Passive vs Active mode: Reconciliation should work in both modes. In passive mode, routes are installed at registration time and should stay installed. In active mode, routes are installed on session up — if a session is Up and the route is missing, reconciliation will reinstall it.

6. Log level change scope: Only the passive/peer-passive session down messages are promoted to INFO. The "not installed or not desired" no-op case (line ~829) stays at DEBUG since it's routine and high-frequency.

Testing Strategy

1. Unit test: missing route is reinstalled — Mock the netlinker to return an empty kernel route list. Register a route, mark it as installed. Run reconcileRoutes(). Verify RouteAdd was called.

2. Unit test: present route is not reinstalled — Mock the netlinker to return the route in the kernel. Register a route, mark it as installed. Run reconcileRoutes(). Verify RouteAdd was NOT called (or was called 0 additional times).

3. Unit test: uninstalled route is not reinstalled — Register a route but don't mark it as installed (e.g., session is Down in active mode). Run reconcileRoutes(). Verify RouteAdd was NOT called.

4. Unit test: log level change — Verify session down in passive mode logs at INFO (can test via log capture or by checking the code path).

5. Existing tests: Run make go-test and make go-lint to ensure no regressions.

Estimated Scope

Category	Lines
liveness/manager.go — reconciliation method + goroutine	~60
liveness/manager.go — config field + validation	~10
liveness/manager.go — log level changes	~4 (changed, not new)
liveness/metrics.go — new metric	~10
cmd/doublezerod/main.go — flag + wiring	~5
Total new lines (excluding tests)	~85

This is well within the 500-line threshold. No need to split into multiple issues.

Open Questions

None — the approach is straightforward and stays within the existing architecture.

[nikw9944]

Architecture review findings:

• Critical: 0
• High: 1
• Medium: 3
• Low: 4

Architecture Review

Critical

None

High

• [Race Condition / State Consistency]: In onSessionUp, installed[rk] is set to true before RouteAdd is called (lines 786-790). If RouteAdd fails, the route is marked as installed but never actually reached the kernel. The reconciliation loop then sees it as installed=true with a missing kernel entry and attempts reinstallation -- which is actually a desirable self-healing behavior. However, if RouteAdd continues failing (e.g., bad route parameters), reconciliation will log a WARN and retry every 30 seconds indefinitely with no backoff. This is a pre-existing design choice in onSessionUp, but the new reconciliation loop amplifies its impact.
  • Location: client/doublezerod/internal/liveness/manager.go:786-796 (pre-existing) amplified by :957-971 (new)
  • Recommendation: Consider either (a) rate-limiting repeated reinstall failures per route (e.g., exponential backoff per RouteKey), or (b) tracking a failure count and suppressing the WARN log after N consecutive failures for the same route. At minimum, this is worth documenting as accepted behavior.
  • Resolution: Accepted as-is. The 30s interval is conservative, RouteAdd uses idempotent RouteReplace, and a RouteInstallFailures counter increment was added in a follow-up commit to ensure observability.

Medium

• [Validate Semantics / Backward Compatibility]: Validate() now sets RouteReconcileInterval = defaultRouteReconcileInterval when the value is zero. The config field doc says "Zero disables", but Validate() converts zero to 30s. This means there is no way to disable reconciliation through the config struct without using a negative duration, which is unintuitive and undocumented. The CLI flag help text says "0 disables" but the actual behavior is that zero becomes 30s after validation.

  • Location: client/doublezerod/internal/liveness/manager.go:162-164 and :100-102
  • Recommendation: Either (a) use a sentinel like -1 as the documented disable value and reject other negatives in Validate, or (b) use a *time.Duration (pointer) so nil means "use default" and zero genuinely means disabled. The current pattern where tests pass -1 to disable works but relies on negative-duration being silently accepted by NewManager's cfg.RouteReconcileInterval > 0 guard, which is fragile.

• [IPv4-Only Key Matching]: The kernelKey in reconcileRoutes and the RouteKey construction in routeKeyFor both call .To4() on IPs, silently producing empty strings for IPv6 routes. If an IPv6 route were ever registered, reconciliation would match on empty-string keys and could spuriously reinstall or skip routes. This mirrors the existing routeKeyFor behavior, but the kernel lookup builds its own key structure independently, creating a second place where this assumption must hold.

  • Location: client/doublezerod/internal/liveness/manager.go:946-953
  • Recommendation: At minimum, add a code comment noting the IPv4-only assumption. Ideally, use a shared key-construction helper rather than duplicating the IP-to-string logic.

• [Missing Error Metric on Reinstall Failure]: When RouteAdd fails during reconciliation, only a log is emitted. There is no RouteInstallFailures counter increment (unlike the onSessionUp path at line 793 which does increment RouteInstallFailures). This creates an observability gap -- operators watching dashboards for install failures will not see reconciliation failures.

  • Location: client/doublezerod/internal/liveness/manager.go:967-969
  • Recommendation: Increment m.metrics.RouteInstallFailures.WithLabelValues(ir.rk.Interface, ir.rk.SrcIP).Inc() on reinstall failure, or introduce a dedicated RouteReinstallFailures counter.
  • Resolution: Fixed in follow-up commit — RouteInstallFailures counter is now incremented on reinstall failure.

Low

• [Log Level Change]: Promoting session down log messages from DEBUG to INFO for passive/peer-passive modes is a reasonable operational improvement but will increase log volume in environments with many passive peers experiencing frequent session flaps. Since these sessions intentionally keep routes installed, the INFO-level logs may appear alarming without the additional context that routes are unaffected.

  • Location: client/doublezerod/internal/liveness/manager.go:867,881
  • Recommendation: The log messages already contain "(global passive; keeping route)" / "(peer passive; keeping route)" which provides sufficient context. This is fine as-is, but consider adding a total count or rate-limiting if log volume becomes a concern.

• [Test Data Race on addCalls]: In the reconcile tests, addCalls is a plain int captured by the RouteAddFunc closure, which is called under mock.mu.Lock(). The test resets addCalls under mock.mu.Lock() and reads it under mock.mu.Lock(). This is correct, but the initial addCalls := 0 declaration at function scope and the RouteAddFunc closure access form a pattern that is easy to accidentally break if someone adds a concurrent call. The variable should ideally be a field on the mock or use atomic.Int32.

  • Location: client/doublezerod/internal/liveness/manager_test.go:1656,1680-1683,1687-1689
  • Recommendation: Use atomic.Int32 for addCalls or move the counter into the mock struct to make the thread-safety explicit and harder to break.

• [No Test for RouteAdd Failure in Reconciliation]: The tests cover the reinstall-missing, skip-present, and skip-uninstalled cases but do not test the error path where RouteAdd fails during reconciliation. This would verify that the error is logged and no metric is emitted (or that the correct metric is emitted, per the Medium finding above).

  • Location: client/doublezerod/internal/liveness/manager_test.go
  • Recommendation: Add a test where RouteAddFunc returns an error to verify error handling behavior.

• [Naming]: The reconcileRoutes method is well-named and the installedRoute local type is clear. Minor nit: toCheck could be named expected or shouldBeInstalled to better convey intent, but this is subjective.

  • Location: client/doublezerod/internal/liveness/manager.go:918
  • Recommendation: Optional rename for clarity.

Summary

This is a well-structured addition that solves a real operational problem (externally-deleted routes causing connectivity loss). The core reconciliation logic is correct: it snapshots state under lock, performs the expensive kernel query outside the lock, and uses an efficient set-based lookup. The main areas for improvement are the zero-vs-negative disable semantics in Validate(), adding failure metrics to match the existing onSessionUp observability pattern, and considering backoff for persistently failing reinstalls.

[nikw9944]

Security review findings:

• Critical: 0
• High: 0
• Medium: 1
• Low: 3

Security Review

Critical

None

High

None

Medium

• [Race Condition on addCalls counter in tests]: The addCalls variable in tests is accessed both inside the RouteAddFunc callback (which could be called from any goroutine) and from the test goroutine without consistent synchronization. While mock.mu.Lock() is used around the assertions, the RouteAddFunc callback itself increments addCalls without holding that lock. This is a test-only data race, not a production issue.
  • Location: client/doublezerod/internal/liveness/manager_test.go:1660-1665
  • Recommendation: Increment addCalls inside the callback while holding mock.mu, or use atomic.AddInt32 instead.
  • Note: The MockRouteReaderWriter.RouteAdd() method acquires mock.mu.Lock() before calling RouteAddFunc, so addCalls++ does run under the lock. The test reads/resets also acquire the lock. There is no actual data race here.

Low

• [Negative duration accepted for RouteReconcileInterval]: The Validate() method only checks for zero to apply the default; a negative value (e.g., -1) passes validation and is used in tests to disable the ticker. However, time.NewTicker panics when given a non-positive duration. In production, a user could pass --route-liveness-reconcile-interval=-1s to reach the time.NewTicker call (the cfg.RouteReconcileInterval > 0 guard in NewManager prevents this for negative values, so the panic is actually unreachable). The guard is correct but the defense is implicit rather than explicit in Validate().

  • Location: client/doublezerod/internal/liveness/manager.go:162-164 (Validate) and manager.go:305 (guard)
  • Recommendation: Add explicit validation in Validate() rejecting negative values, e.g., if c.RouteReconcileInterval < 0 { return errors.New("RouteReconcileInterval must be >= 0") }. This makes the contract explicit and prevents future refactors from accidentally removing the > 0 guard.

• [Log level promotion from DEBUG to INFO]: Changing session-down log messages from Debug to Info in passive modes is intentional per the description, but in high-churn environments with many passive peers, this could increase log volume substantially, potentially contributing to log-based denial-of-service or masking other important messages.

  • Location: client/doublezerod/internal/liveness/manager.go:867,878
  • Recommendation: Consider rate-limiting these log messages or documenting the expected volume impact. This is a very minor operational concern.

• [Unbounded toCheck slice allocation]: The reconcileRoutes function collects all installed-and-desired routes into a slice without a size hint or cap. In a deployment with a very large number of routes, this could cause transient memory spikes during reconciliation, though this is bounded by the number of BGP routes which is typically manageable.

  • Location: client/doublezerod/internal/liveness/manager.go:916-924
  • Recommendation: Pre-allocate with make([]installedRoute, 0, len(m.installed)) to avoid repeated slice growth.
  • Resolution: Fixed in follow-up commit — toCheck is now pre-allocated.

Summary

This is a low-risk change. The code runs as a local daemon with root privileges (already required for kernel route manipulation), introduces no new external inputs, and performs no injection-susceptible operations. The reconciliation logic correctly snapshots state under the lock and releases it before performing I/O. The only actionable item is adding explicit negative-duration validation in Validate() to harden the contract.

[nikw9944]

Work Log — waiting_review

I'll start by reading the project instructions and then exploring the relevant code areas in parallel.

Good, I have thorough understanding of the codebase. Let me read the specific files I need to modify.

Now let me read the critical sections of manager.go.

Let me also check the routing.Route type and the routerw.go interface.

Let me check the routing.Route struct and the routeKey function used in the liveness manager.

Now let me see the full routeKeyFor function and also check how routeKey is used for kernel routes (to understand how to build a matching key from kernel-returned routes).

Now let me read the onSessionUp method and the full onSessionDown to understand the complete pattern.

I have all the context I need. Let me implement the changes. I'll work on all four files.

Now let me implement the changes. I'll start with the config/constant addition to manager.go and the metrics change in parallel.

Now add the default in Validate(), the metric initialization, registration, and helper.

Now add the helper method to metrics.go and do the remaining manager.go changes.

Now I need to add the unix import to manager.go and then add the reconcileRoutes method and goroutine. Let me add the import first.

Now add the reconciliation goroutine in NewManager() after the scheduler goroutine, and the reconcileRoutes method. Let me read the exact context around where I need to insert the goroutine.

Now add the reconcileRoutes method. Let me find the right place to insert it — after onSessionDown and before isPeerEffectivelyPassive.

I'll insert the reconcileRoutes method after onSessionDown and before isPeerEffectivelyPassive.

Now change the log levels for session down in passive/peer-passive modes, and update main.go.

Now wire the flag into the ManagerConfig.

Now let me write the unit tests. First let me look at how existing tests set up the manager to understand the patterns.

Let me find the newTestManager helper function.

Good, I now understand the test patterns. Let me find the end of the test file to append the new tests.

Now I'll write the test. The test needs to directly call reconcileRoutes() on the manager, manipulating the internal state. Since we're in the same package (liveness), we have access to internal fields.

Now let me verify the changes compile and pass tests.

Build succeeds. Now let me run the liveness tests.

All 3 tests pass. Now let me run the full liveness test suite and the Go lint.

All tests pass and vet is clean. Let me now run go fmt and check lint.

Good, formatting is applied. Now let me commit the changes and proceed to the review phase.

Let me commit the changes first, then get the diff for the reviews.

Now let me get the diff for the reviews and launch both review agents in parallel.

Now let me launch both review agents in parallel.

Both reviews returned with no Critical findings. Let me address the Medium findings. The main actionable item is the missing RouteInstallFailures metric increment on reinstall failure. Let me also pre-allocate the toCheck slice.

Now let me commit the fix and post the reviews.

Now post the reviews as GitHub issue comments.

Reviews posted. No critical or high findings remain unresolved (the one High was accepted and the Medium metric finding was fixed). Let me now proceed to final verification — rebase onto main, run full tests, and create the PR.

Already up to date. Let me run the full test and build verification.

All passing. Let me push and create the PR.

Now let me generate the PR description and create the draft PR.

STATUS: COMPLETE

PR created: #3672

Summary of changes:

1. Route reconciliation (manager.go): Added reconcileRoutes() method and a ticker goroutine that runs every 30s (configurable via RouteReconcileInterval). It snapshots installed/desired routes under the lock, queries the kernel for BGP routes via RouteByProtocol, and reinstalls any missing routes with RouteAdd.

2. Metrics (metrics.go): Added doublezero_liveness_route_reinstalls_total counter. Also increments route_install_failures_total on failed reinstalls for consistency with onSessionUp.

3. Log level fix (manager.go): Promoted session-down logs from DEBUG to INFO for passive/peer-passive modes so operators see the full up/down lifecycle.

4. CLI flag (main.go): Added --route-liveness-reconcile-interval (default 30s).

5. Tests (manager_test.go): Three tests covering missing route reinstall, present route skip, and uninstalled route skip.

--- Result: success | Session cost: $4.4895 | Turns: 77 | Tokens: 2221 in / 34250 out | 2026-05-05 20:20:47 UTC ---

[nikw9944]

Work Log — waiting_review

Let me investigate the CI failure. The failing check is "changelog".

The CI check requires either a CHANGELOG.md update or a skip-changelog label. Let me look at the existing CHANGELOG format and the branch changes to craft the right entry.

Now I understand the issue. I need to add a changelog entry for the doublezerod route reconciliation feature. Let me check the PR number.

PR #3672. Now let me add the changelog entry under the Unreleased Changes section. The feature belongs under "Client" since doublezerod is the client daemon.

Need more context to make the edit unique.

Now let me verify the change looks correct and then commit and push.

Looks good. Now commit and push.

STATUS: COMPLETE

The CI failure was caused by the changelog check requiring a CHANGELOG.md update for every PR. I added a changelog entry under ## Unreleased > ### Changes > Client describing the periodic kernel route reconciliation feature added to doublezerod, referencing issue #3669.

--- Result: success | Session cost: $0.4351 | Turns: 10 | Tokens: 11 in / 1689 out | 2026-05-05 20:24:14 UTC ---

[nikw9944]

Work Log — waiting_review

Now let me update the PR body.

The gh token doesn't have the read:org scope needed to edit the PR via GraphQL. Let me try using the REST API directly.

PR body updated: #3672

STATUS: COMPLETE

--- Result: success | Session cost: $0.4440 | Turns: 11 | Tokens: 10 in / 3549 out | 2026-05-05 20:30:18 UTC ---

[nikw9944]

Work Log — waiting_review

There's no code-review skill available. Let me do a thorough review manually, with special attention to concurrency. Let me read all the changed files in full.

Code Review: PR #3672 — Periodic Kernel Route Reconciliation

Concurrency Issues

1. TOCTOU race: reconcileRoutes can resurrect an intentionally-deleted route (Medium)
manager.go — reconcileRoutes() snapshots m.installed and m.desired under m.mu, then releases the lock before scanning the kernel and calling RouteAdd. Between the snapshot and the reinstall, onSessionDown can run, set installed[rk] = false, and call RouteDelete. Reconciliation then finds the route missing from the kernel and calls RouteAdd — reinstalling a route for a dead session.

The ghost route persists until the next down event or session re-up. In passive mode (the primary use case) this can't happen because onSessionDown doesn't delete routes. But in active mode it's a real concern.

Fix: Re-check m.installed[rk] under lock before each RouteAdd:

m.mu.Lock()
stillInstalled := m.installed[ir.rk]
m.mu.Unlock()
if !stillInstalled {
    continue
}

2. onSessionUp marks installed[rk] = true before RouteAdd succeeds (Pre-existing, mitigated)
manager.go:786-794 — If RouteAdd fails, the route is marked installed but never actually added. The new reconciliation loop actually improves this: it will detect the missing kernel route and retry the install. So this is a net positive, though the underlying issue remains.

Correctness Issues

3. Kernel route lookup key omits source IP and interface (Low-Medium)
manager.go:940-958 — kernelKey is {Table, DstIP, NextHop}, but RouteKey also has Interface and SrcIP. In multi-interface setups, a kernel route matching one managed route could suppress reconciliation for a different route with the same destination/nexthop but different source/interface. Consider adding source IP to the kernelKey for tighter matching, if netlink.Route provides it.

4. Validate() does not reject negative RouteReconcileInterval (Minor)
manager.go:162-164 — Zero defaults to 30s, but negative values silently pass validation and then get treated as "disabled" by the > 0 guard in NewManager. Tests intentionally use -1 for this, but it's an undocumented API quirk. Either validate explicitly or document the behavior.

Minor Issues

5. Flag default duplicates the const
main.go:53 hardcodes 30*time.Second as the flag default while manager.go:31 defines defaultRouteReconcileInterval = 30 * time.Second. If someone changes one they'll miss the other. The flag should reference the package const, or the const should be removed since Validate() also defaults zero.

6. No startup log for reconciliation
The reconciliation goroutine starts silently. Other config values are logged at NewManager startup (line 247). A one-liner like "liveness: route reconciliation enabled, interval=30s" would help operators confirm the feature is active.

7. installed map false vs delete inconsistency (Pre-existing)
onSessionDown sets installed[rk] = false; WithdrawRoute uses delete(m.installed, rk). The false entries are never cleaned up, so InstalledMapSize counts both live and dead entries. Reconciliation handles this correctly (skips !ok), but it's a pre-existing wart.

Verdict

The implementation is solid overall. The main actionable finding is issue #1 — the TOCTOU race in active mode. The one-line re-check fix eliminates it. Issues #3 and #5 are worth addressing; the rest are informational.

--- Result: success | Session cost: $1.3857 | Turns: 3 | Tokens: 5 in / 1686 out | 2026-05-05 20:36:01 UTC ---

[nikw9944]

Work Log — waiting_review

Now let me read the rest of reconcileRoutes and check for the Src field on kernel routes.

Let me check the Route struct to see how Src is available.

Good, Route has Src net.IP and RouteByProtocol populates it. Now let me also check how defaultRouteReconcileInterval is imported (or could be imported) in main.go.

Now let me check how other defaults from liveness are referenced in main.go.

I see — the other liveness defaults are defined locally in main.go, not imported from the liveness package. The defaultRouteReconcileInterval is unexported (lowercase) in manager.go. So for issue #5, the cleanest fix is to use liveness.DefaultRouteReconcileInterval — but that requires exporting the const. Let me check if there's a simpler approach: just define the default locally in main.go like the others, and remove the unused const from manager.go (since Validate() also defaults zero to 30s). Actually, looking more carefully, Validate() uses defaultRouteReconcileInterval to default zero. So both are needed. The cleanest fix following the existing pattern: add a local const in main.go too, matching the pattern of the other defaults.

Actually, the best fix is to just reference the same default in both places consistently. Let me follow the existing pattern — add a defaultRouteLivenessReconcileInterval const in main.go (matching the other naming) and use it in the flag declaration.

Now let me also read the test file to understand how to update it for issue #3 (adding SrcIP to kernelKey).

Now let me check where the install failure test is.

Now let me look at newTestRoute to understand the default Src value in tests.

Good. Now I have everything I need. Let me apply all fixes:

1. Issue controlplane: open source controller/agent #1 — Re-check m.installed[rk] before RouteAdd in reconcileRoutes
2. Issue client: open source doublezero client #3 — Add SrcIP to kernelKey for tighter matching
3. Issue #4 — Reject negative RouteReconcileInterval in Validate()
4. Issue agent: rename eosagent to agent #5 — Use a local const in main.go matching the existing pattern
5. Issue build(deps): bump golang.org/x/net from 0.31.0 to 0.33.0 in the go_modules group across 1 directory #6 — Log at startup when reconciliation is enabled

Now fix issue #3 (add SrcIP to kernelKey) and issue #1 (re-check installed before RouteAdd):

Now fix issue #5 — add a local const in main.go and reference it:

Now update the tests — issue #4 means the tests using -1 for RouteReconcileInterval will fail validation. I need to change the test approach. Since Validate() now rejects negative values and the tests create the manager via newTestManagerWithMetrics which calls Validate(), I need a different way to disable the ticker in tests. Let me check how the test helper works.

The tests use RouteReconcileInterval = -1 to disable the ticker. With the new validation, I need to switch to a large interval instead. The tests call reconcileRoutes() manually so the ticker never needs to fire.

Now let me also check newTestManagerWithMetrics — the default doesn't set RouteReconcileInterval, so Validate() will default it to 30s and start the reconciliation goroutine. I need to check if the MockRouteReaderWriter's RouteByProtocolFunc handles nil correctly since most tests don't set it.

Good — RouteByProtocolFunc == nil returns nil, nil which is safe. The reconciliation goroutine with a 30s default won't cause problems in short-lived tests because it'll only fire if the test runs for 30+ seconds.

Now let me run the tests to verify:

All 4 tests pass. Let me also run the Validate test to make sure nothing else broke there.

Let me also run the full liveness test suite and the build to make sure nothing else broke.

All liveness tests pass and doublezerod builds clean. Let me also run the Go linter on the changed files.

Clean. Now let me format and commit.

Good — gofmt cleaned up the alignment in main.go. Let me verify the final state of all changes and commit.

Everything looks correct. Let me commit and push.

All 5 review issues fixed, tests passing, pushed.

Summary of changes:

1. TOCTOU race fix — Re-check m.installed[rk] under lock before each RouteAdd in reconcileRoutes, preventing resurrection of intentionally-withdrawn routes
2. Kernel key tightened — Added SrcIP to kernelKey so routes with same (table, dst, nexthop) but different source IPs are matched independently
3. Negative interval rejected — Validate() now returns an error for negative RouteReconcileInterval; tests switched from -1 to time.Hour
4. Flag default deduped — Added defaultRouteLivenessReconcileInterval const in main.go, referenced by the flag (matching the pattern of all other liveness defaults)
5. Startup log added — Reconciliation goroutine now logs "liveness: route reconciliation enabled" with the interval at startup

--- Result: success | Session cost: $1.4886 | Turns: 41 | Tokens: 34 in / 8194 out | 2026-05-05 20:45:35 UTC ---

[nikw9944]

Work Log — waiting_review

PR body updated: #3672

--- Result: success | Session cost: $0.5308 | Turns: 4 | Tokens: 6 in / 1352 out | 2026-05-05 20:58:59 UTC ---

[nikw9944]

Work Log — waiting_review

The branch is already up to date with origin/main (merge base is the latest main commit). Now let me run the build and tests for the affected components.

The changes are in the Go doublezerod component. Let me build and test it.

Build passes. Now let me run the tests for the changed package.

All tests pass. Let me also run lint on the changed files.

Everything is clean — build passes, all tests pass, lint clean, formatting clean. The branch is already up to date with main. Now let me push.

STATUS: COMPLETE

• Base branch integration: Branch was already up to date with origin/main (merge base at latest main commit 77c69614)
• CI checks: All passing — Go build, 40+ tests in the liveness package, golangci-lint (0 issues), gofmt clean
• PR review feedback: No review comments to address
• Push: Successfully pushed to origin

--- Result: success | Session cost: $0.3345 | Turns: 19 | Tokens: 19 in / 2196 out | 2026-05-05 21:12:16 UTC ---

Go builds. Now let me run Go lint and the Go tests relevant to the changed code (client/doublezerod).

The test failures are multicast-related (raw socket operation not permitted) - these need sudo and are unrelated to the route reconciliation changes. Let me verify by running the lint without Docker and the route-specific tests.