IP6 always returns - .... connect: invalid argument

[krasi-georgiev]

google.golang.org/grpc v1.36.0-dev.0.20210122012134-2c42474aca0c
go version go1.15.6 linux/arm
linux rpi

	lis, err := net.Listen("tcp", ":9999")
	if err != nil {
		return errors.Wrapf(err, "create network listener")
	}
	s := grpc.NewServer()

	RegisterAudiorServer(s, &Server{})
	reflection.Register(s)

	func (self *Server) Record(ctx context.Context, req *Request) (*Response, error) {
		fmt.Println("called!!!!")
		return &Response{ErrorType: "audior"}, nil

	}

syntax = "proto3";
package audior;


service Audior {
  rpc Record (Request) returns (Response) {}
}

message Request{
  enum event {
    None = 0;
    AudioRecordStart = 1;
    AudioRecordStop = 2;
  }
  event Event = 1;
}

message Response {
  string ErrorType     = 1;
  string Error         = 2;
}

protoc --gofast_out=plugins=grpc:. pkg/node/audior/audior.proto

What did you expect to see?

It works with ip4 , but not ip6 , the same error when using grpccurl or calling from grpc client from go.

What did you see instead?

grpcurl -plaintext -d '{"Event": 2}' [fe80::6396:e2a6:8607:e10f]:9990 audior.Audior/Record
Failed to dial target host "[fe80::6396:e2a6:8607:e10f]:9990": dial tcp [fe80::6396:e2a6:8607:e10f]:9990: connect: invalid argument

netstat -tulpn | grep LISTEN
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      556/sshd            
tcp        0      0 127.0.0.1:32903         0.0.0.0:*               LISTEN      9612/node           
tcp6       0      0 :::22                   :::*                    LISTEN      556/sshd            
tcp6       0      0 :::9990                 :::*                    LISTEN      12523/i360          
tcp6       0      0 :::9999                 :::*                    LISTEN      12523/i360          
root@raspberrypi:~/src/github.com/arribada/i360# ifconfig 
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.0.101  netmask 255.255.255.0  broadcast 192.168.0.255
        inet6 fe80::6396:e2a6:8607:e10f  prefixlen 64  scopeid 0x20<link>
        ether dc:a6:32:d2:00:b6  txqueuelen 1000  (Ethernet)
        RX packets 312650  bytes 102090189 (97.3 MiB)
        RX errors 0  dropped 0  overruns 0  frame 1242
        TX packets 263220  bytes 52487031 (50.0 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

[menghanl]

Can you turn on logs and see what that says: https://github.com/grpc/grpc-go#how-to-turn-on-logging

And it seems proxy is on in your environment. Try to turn that off?

[krasi-georgiev]

There is no proxy. What made you think that there is proxy?

[krasi-georgiev]

Here is the update with the verbose loggs.
I am running these commands on RPI. I am running grpccurl from the same host where the grpc server is running

The strange thing is that when running the command to ::1 is works as expected.

root@raspberrypi:~/src/github.com/arribada/i360# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.0.101  netmask 255.255.255.0  broadcast 192.168.0.255
        inet6 fe80::6396:e2a6:8607:e10f  prefixlen 64  scopeid 0x20<link>
        ether dc:a6:32:d2:00:b6  txqueuelen 1000  (Ethernet)
        RX packets 575776  bytes 131128694 (125.0 MiB)
        RX errors 0  dropped 0  overruns 0  frame 1716
        TX packets 493991  bytes 93537129 (89.2 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 1048321  bytes 149810864 (142.8 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 1048321  bytes 149810864 (142.8 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

root@raspberrypi:~/src/github.com/arribada/i360# grpcurl -plaintext -d '{"Event": 1}' [::1]:9999 audior.Audior/Record
INFO: 2021/01/25 11:38:27 [core] parsed scheme: ""
INFO: 2021/01/25 11:38:27 [core] scheme "" not registered, fallback to default scheme
INFO: 2021/01/25 11:38:27 [core] ccResolverWrapper: sending update to cc: {[{[::1]:9999  <nil> 0 <nil>}] <nil> <nil>}
INFO: 2021/01/25 11:38:27 [core] ClientConn switching balancer to "pick_first"
INFO: 2021/01/25 11:38:27 [core] Channel switches to new LB policy "pick_first"
INFO: 2021/01/25 11:38:27 [core] Subchannel Connectivity change to CONNECTING
INFO: 2021/01/25 11:38:27 [core] Subchannel picks a new address "[::1]:9999" to connect
INFO: 2021/01/25 11:38:27 [core] pickfirstBalancer: UpdateSubConnState: 0x280ec40, {CONNECTING <nil>}
INFO: 2021/01/25 11:38:27 [core] Channel Connectivity change to CONNECTING
INFO: 2021/01/25 11:38:27 [core] Subchannel Connectivity change to READY
INFO: 2021/01/25 11:38:27 [core] pickfirstBalancer: UpdateSubConnState: 0x280ec40, {READY <nil>}
INFO: 2021/01/25 11:38:27 [core] Channel Connectivity change to READY
{
  
}
INFO: 2021/01/25 11:38:28 [core] Channel Connectivity change to SHUTDOWN
INFO: 2021/01/25 11:38:28 [core] Subchannel Connectivity change to SHUTDOWN
root@raspberrypi:~/src/github.com/arribada/i360# grpcurl -plaintext -d '{"Event": 1}' [fe80::6396:e2a6:8607:e10f]:9999 audior.Audior/Record
INFO: 2021/01/25 11:38:38 [core] parsed scheme: ""
INFO: 2021/01/25 11:38:38 [core] scheme "" not registered, fallback to default scheme
INFO: 2021/01/25 11:38:38 [core] ccResolverWrapper: sending update to cc: {[{[fe80::6396:e2a6:8607:e10f]:9999  <nil> 0 <nil>}] <nil> <nil>}
INFO: 2021/01/25 11:38:38 [core] ClientConn switching balancer to "pick_first"
INFO: 2021/01/25 11:38:38 [core] Channel switches to new LB policy "pick_first"
INFO: 2021/01/25 11:38:38 [core] Subchannel Connectivity change to CONNECTING
INFO: 2021/01/25 11:38:38 [core] Subchannel picks a new address "[fe80::6396:e2a6:8607:e10f]:9999" to connect
INFO: 2021/01/25 11:38:38 [core] pickfirstBalancer: UpdateSubConnState: 0x280f580, {CONNECTING <nil>}
WARNING: 2021/01/25 11:38:38 [core] grpc: addrConn.createTransport failed to connect to {[fe80::6396:e2a6:8607:e10f]:9999 [fe80::6396:e2a6:8607:e10f]:9999 <nil> 0 <nil>}. Err: connection error: desc = "transport: error while dialing: dial tcp [fe80::6396:e2a6:8607:e10f]:9999: connect: invalid argument". Reconnecting...
INFO: 2021/01/25 11:38:38 [core] Channel Connectivity change to CONNECTING
Failed to dial target host "[fe80::6396:e2a6:8607:e10f]:9999": dial tcp [fe80::6396:e2a6:8607:e10f]:9999: connect: invalid argument
root@raspberrypi:~/src/github.com/arribada/i360# 

[krasi-georgiev]

I think it might have something to do with the fact that the ip6 address is fe80 - link local.

[menghanl]

What made you think that there is proxy?

I thought the connect: error was from HTTP CONNECT. But it seems I was wrong.

I think it might have something to do with the fact that the ip6 address is fe80 - link local.

This sound right. Try to specify zone_index?

[krasi-georgiev]

Yeah I already tried it after reading that article as well, but didn't make any difference 😞

[menghanl]

Does net.Dial work with that address? If not, you may want to seek help in the golang repo.

[krasi-georgiev]

yep good point, I tried it with the same results so opened an issue on golang repo
golang/go#43950