no free connections available to host

[imtiazwazir]

I have following server setup and getting "no free connections available to host" any reason why? I did try many variations but none worked.

server := &fasthttp.Server{
	Handler:            router.Handler,
	ReadBufferSize:     util.KBToBytes(16),
	WriteBufferSize:    util.KBToBytes(16),
	ReadTimeout:        time.Millisecond * 600,
	WriteTimeout:       time.Millisecond * 600,
	// IdleTimeout:        time.Second * 2,
	MaxRequestBodySize: util.MBToBytes(8),
	ReduceMemoryUsage:  false,
	MaxConnsPerIP:      10000,
	MaxRequestsPerConn: 10000,
	Concurrency:        1024 * 1024,
	LogAllErrors:       false,
	// TCPKeepalive:       true,
	// TCPKeepalivePeriod: time.Minute * 5,
}

config.Logger.Info("Server is starting on port 8080...")

if err := server.ListenAndServe(":8080"); err != nil {
	config.Logger.Error("Error in ListenAndServe", "err", err)
}

[erikdubbelboer]

What is generating the no free connections available to host message? Have you tried measuring how many concurrent requests you are receiving and if 10000 connections is enough for that?

I would not set MaxRequestsPerConn if not needed. This will force close connections after this many requests and is only needed for broken clients.

[imtiazwazir]

the thing is requests never reached to that value and still I am seeing that error no free connections available to host I am not sure if .Server also account 512 requests

[erikdubbelboer]

How many requests are you sending per second before you get that error? How long does your handler take to send a response?