fix: check existing routes before installing pod subnet route#177
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configureHostVethGateway used netlink.RouteReplace to install the pod-subnet route in the VRF table, which silently overwrote any existing route without warning. Replace it with a pre-flight check that lists existing routes, compares them for conflicts, and uses RouteAdd with an EEXIST guard for safe idempotency. - check for existing routes with the same destination before installing - return a clear error when an existing route has a different gateway - skip installation when the route already matches desired attributes - use RouteAdd instead of RouteReplace to prevent silent overwrites - extract routeConflicts as a testable pure function - add unit tests covering all conflict detection scenarios fixes #158
scotwells
approved these changes
Jun 30, 2026
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configureHostVethGateway used netlink.RouteReplace to install the pod-subnet route in the VRF table, which silently overwrote any existing route without warning. Replace it with a pre-flight check that lists existing routes, compares them for conflicts, and uses RouteAdd with an EEXIST guard for safe idempotency.
fixes #158