Don't require probes to pass in router worker sync - #4313
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The sync only picked up router and worker jobs with `JobModel.ready`, i.e. with all probes passed. A router probe that depends on registered workers, such as `/health_generate`, never passed, since workers are only registered once the router is picked up, so the service deadlocked. The sync now takes all running jobs, filtered by `job_num == 0` instead. Workers are registered once the sync's own check (`/server_info` or `GetServerInfo`) reports them ready, so `probes` can no longer delay worker registration. As probes are configured per service, not per replica group, such gating only worked when the router and workers share the transport and API. The `job_num == 0` condition is a no-op for now, as services don't support multi-node replicas. Previously, it was implied by `ready`, which is only set for the first node. Fixes: #4310 Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
…orker_sync_ignore_probes
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Since #4270, a router replica of a service with `model` and no `probes` was probed with `GET /health` instead of the chat completions request. The latter deadlocked: the router only answers it once workers are registered, and the worker sync skipped routers that were not ready. #4313 dropped the readiness check from the sync, so this deadlock is gone. `/health` passes before the router has any workers. In a rolling deployment, the replacement router was considered ready, and the old one was scaled down, before the replacement could serve requests. Now that #4320 syncs workers with every running router, the replacement passes the chat completions probe once it has workers. Workers behind a router still get no default probe, as they may not serve HTTP at all (gRPC workers). With a Dynamo router, a router rolling deployment now waits for the replacement indefinitely instead of scaling down the old router, as workers stay attached to the old router's etcd/NATS. Such deployments were broken before as well and are to be fixed separately. Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
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The sync only picked up router and worker jobs with
JobModel.ready, i.e. with all probes passed. A router probe that depends on registered workers, such as/health_generate, never passed, since workers are only registered once the router is picked up, so the service deadlocked.The sync now takes all running jobs, filtered by
job_num == 0instead. Workers are registered once the sync's own check (/server_infoorGetServerInfo) reports them ready, soprobescan no longer delay worker registration. As probes are configured per service, not per replica group, such gating only worked when the router and workers share the transport and API.The
job_num == 0condition is a no-op for now, as services don't support multi-node replicas. Previously, it was implied byready, which is only set for the first node.Fixes: #4310