Teach Nomad servers how to fall back to Consul. #1276
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| @@ -63,8 +66,14 @@ func testServer(t *testing.T, cb func(*Config)) *Server { | |||
| // Enable raft as leader if we have bootstrap on | |||
| config.RaftConfig.StartAsLeader = !config.DevDisableBootstrap | |||
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| shutdownCh := make(chan struct{}) | |||
| consulSyncer, err := consul.NewSyncer(config.ConsulConfig, shutdownCh, log.New(os.Stderr, "", log.LstdFlags)) | |||
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You shouldn't have to make a new logger should be one in the config I believe
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LGTM |
Client: Search limit increased from 4 random DCs to 8 random DCs, plus nearest. Server: Search factor increased from 3 to 5 times the bootstrap_expect. This should allow for faster convergence in large environments (e.g. sub-5min for 10K Consul DCs).
Per discussion, we want to be aggressive about fanning out vs possibly fixating on only local DCs. With RPC forwarding in place, a random walk may be less optimal from a network latency perspective, but it is guaranteed to eventually result in a converged state because all DCs are candidates during the bootstrapping process.
It is perfectly viable for an admin to downsize a Nomad Server cluster down to 1, 2, or `num % 2 == 0` (however ill-advised such activities may be). And instead of using `bootstrap_expect`, use a timeout-based strategy. If the `bootstrapFn` hasn't observed a leader in 15s it will fall back to Consul and will poll every ~60s until it sees a leader.
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| consulServices, _, err := consulCatalog.Service(nomadServerServiceName, consul.ServiceTagSerf, consulOpts) | ||
| if err != nil { | ||
| s.logger.Printf("[WARN] server.consul: failed to query service %+q in Consul datacenter %+q: %v", nomadServerServiceName, dc, err) | ||
| mErr.Errors = append(mErr.Errors, fmt.Errorf("unable to query service %q from Consul datacenter %q: %v", nomadServerServiceName, dc, err)) |
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I would define the error and then use it in the log and add it to mErr.
Also don't attempt to join the Server with itself.
| @@ -501,6 +511,9 @@ func (s *Server) setupBootstrapHandler() error { | |||
| if addr == "" { | |||
| addr = cs.Address | |||
| } | |||
| if localNode.Addr.String() == addr && int(localNode.Port) == cs.ServicePort { | |||
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Put a comment that we are skipping ourselves
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I'm going to lock this pull request because it has been closed for 120 days ⏳. This helps our maintainers find and focus on the active contributions. |
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It is now possible to omit
retry_joinfrom server configs if Consul is available.