failed to negotiate security protocol: EOF

[tskoyo]

Hey guys, I started learning more about libp2p (and p2p in general). I wanted to create a simple p2p file sharing system. I created a node.go file that should serve both as a sender/receiver. I wanted to test multiple nodes connecting to one node:

func TestConnect_MultipleClients(t *testing.T) {
	numClients := 9
	var wg sync.WaitGroup
	clientErrors := make(chan error, numClients)

	node1Config := helper.BuildNodeConfig("peer-1", 9001)
	node1, err := NewNode(node1Config)
	require.NoError(t, err)

	node1MultiAddr := node1.Host.Addrs()[0].String() + "/p2p/" + node1.Host.ID().String()

	for i := 1; i <= numClients; i++ {
		wg.Add(1)

		go func(clientId int) {
			defer wg.Done()

			clientNodeConfig := helper.BuildNodeConfig(fmt.Sprintf("client-node-%d", clientId), 9001+clientId)
			clientNode, err := NewNode(clientNodeConfig)
			require.NoError(t, err)

			err = clientNode.Connect(node1MultiAddr)
			require.NoError(t, err)

			clientErrors <- nil
		}(i)
	}

	wg.Wait()
	close(clientErrors)

	for err := range clientErrors {
		require.NoError(t, err)
	}
}

It's failing and this is the error I receive:

Connection attempt 1 failed: failed to dial: failed to dial QmPMagGX6Lc7BbKSSR8rSBeZoqjbwgXoUnv953MdXffPUD: all dials failed
  * [/ip4/10.98.0.10/tcp/9001] failed to negotiate security protocol: EOF
Retrying in 1s...
Connection attempt 2 failed: failed to dial: failed to dial QmPMagGX6Lc7BbKSSR8rSBeZoqjbwgXoUnv953MdXffPUD: all dials failed
  * [/ip4/10.98.0.10/tcp/9001] dial backoff
Retrying in 2s...
Connection attempt 3 failed: failed to dial: failed to dial QmPMagGX6Lc7BbKSSR8rSBeZoqjbwgXoUnv953MdXffPUD: all dials failed
  * [/ip4/10.98.0.10/tcp/9001] dial backoff
Retrying in 4s...
Connection attempt 4 failed: failed to dial: failed to dial QmPMagGX6Lc7BbKSSR8rSBeZoqjbwgXoUnv953MdXffPUD: all dials failed
  * [/ip4/10.98.0.10/tcp/9001] failed to negotiate security protocol: EOF

It's interesting when I change the value of numClients to 8, the test is passing.

Can someone help me understand this more deeply?