Easy IoT is a simplest IoT Solution presented by DFRobot
#43410
We use several RLY-8-POE in an industrial control application. Sometimes, a unit will get into a state where it does not respond to commands sent to port 2000 (2000 is what it replies back with to use in response to the UDP for finding the relays). When it is stuck, the Enternet_Com_Control.exe program cannot affect the unit either. Attached are WireShark decodes of trying to talk to the stuck unit. Is there anything we can do short of power cycling the unit to get it operational?

Regards and thanks, Ira Grollman

System.Net.Sockets.SocketException
HResult=0x80004005
Message=An existing connection was forcibly closed by the remote host
Source=System
StackTrace:
at System.Net.Sockets.Socket.BeginReceive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags, AsyncCallback callback, Object state) in f:\dd\NDP\fx\src\net\System\Net\Sockets\Socket.cs:line 4186

This exception was originally thrown at this call stack:
System.Net.Sockets.Socket.BeginReceive(byte[], int, int, System.Net.Sockets.SocketFlags, System.AsyncCallback, object) in Socket.cs

No. Time Source Destination Protocol Length Info
18485 80.118909 192.168.1.79 192.168.1.109 TCP 66 31880 → 2000 [SYN] Seq=0 Win=8192 Len=0 MSS=1460 WS=256 SACK_PERM=1

Frame 18485: 66 bytes on wire (528 bits), 66 bytes captured (528 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: HewlettP_1c:3a:84 (28:80:23:1c:3a:84), Dst: 00:df:38:37:ff:97 (00:df:38:37:ff:97)
Internet Protocol Version 4, Src: 192.168.1.79, Dst: 192.168.1.109
Transmission Control Protocol, Src Port: 31880, Dst Port: 2000, Seq: 0, Len: 0

No. Time Source Destination Protocol Length Info
18486 80.118910 192.168.1.79 192.168.1.109 TCP 66 [TCP Out-Of-Order] 31880 → 2000 [SYN] Seq=0 Win=8192 Len=0 MSS=1460 WS=256 SACK_PERM=1

Frame 18486: 66 bytes on wire (528 bits), 66 bytes captured (528 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: HewlettP_1c:3a:84 (28:80:23:1c:3a:84), Dst: 00:df:38:37:ff:97 (00:df:38:37:ff:97)
Internet Protocol Version 4, Src: 192.168.1.79, Dst: 192.168.1.109
Transmission Control Protocol, Src Port: 31880, Dst Port: 2000, Seq: 0, Len: 0

No. Time Source Destination Protocol Length Info
18504 80.127054 192.168.1.109 192.168.1.79 TCP 60 2000 → 31880 [SYN, ACK] Seq=0 Ack=1 Win=8192 Len=0 MSS=1460

Frame 18504: 60 bytes on wire (480 bits), 60 bytes captured (480 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: 00:df:38:37:ff:97 (00:df:38:37:ff:97), Dst: HewlettP_1c:3a:84 (28:80:23:1c:3a:84)
Internet Protocol Version 4, Src: 192.168.1.109, Dst: 192.168.1.79
Transmission Control Protocol, Src Port: 2000, Dst Port: 31880, Seq: 0, Ack: 1, Len: 0

No. Time Source Destination Protocol Length Info
18521 80.127185 192.168.1.79 192.168.1.109 TCP 54 31880 → 2000 [ACK] Seq=1 Ack=1 Win=64240 Len=0

Frame 18521: 54 bytes on wire (432 bits), 54 bytes captured (432 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: HewlettP_1c:3a:84 (28:80:23:1c:3a:84), Dst: 00:df:38:37:ff:97 (00:df:38:37:ff:97)
Internet Protocol Version 4, Src: 192.168.1.79, Dst: 192.168.1.109
Transmission Control Protocol, Src Port: 31880, Dst Port: 2000, Seq: 1, Ack: 1, Len: 0

No. Time Source Destination Protocol Length Info
18522 80.127186 192.168.1.79 192.168.1.109 TCP 54 [TCP Dup ACK 18521#1] 31880 → 2000 [ACK] Seq=1 Ack=1 Win=64240 Len=0

Frame 18522: 54 bytes on wire (432 bits), 54 bytes captured (432 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: HewlettP_1c:3a:84 (28:80:23:1c:3a:84), Dst: 00:df:38:37:ff:97 (00:df:38:37:ff:97)
Internet Protocol Version 4, Src: 192.168.1.79, Dst: 192.168.1.109
Transmission Control Protocol, Src Port: 31880, Dst Port: 2000, Seq: 1, Ack: 1, Len: 0

No. Time Source Destination Protocol Length Info
18535 80.132809 192.168.1.109 192.168.1.79 TCP 60 2000 → 31880 [RST, ACK] Seq=1 Ack=1 Win=8192 Len=0

Frame 18535: 60 bytes on wire (480 bits), 60 bytes captured (480 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: 00:df:38:37:ff:97 (00:df:38:37:ff:97), Dst: HewlettP_1c:3a:84 (28:80:23:1c:3a:84)
Internet Protocol Version 4, Src: 192.168.1.109, Dst: 192.168.1.79
Transmission Control Protocol, Src Port: 2000, Dst Port: 31880, Seq: 1, Ack: 1, Len: 0

No. Time Source Destination Protocol Length Info
18748 80.948697 192.168.1.109 192.168.1.255 UDP 111 49154 → 6006 Len=69

Frame 18748: 111 bytes on wire (888 bits), 111 bytes captured (888 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: 00:df:38:37:ff:97 (00:df:38:37:ff:97), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 192.168.1.109, Dst: 192.168.1.255
User Datagram Protocol, Src Port: 49154, Dst Port: 6006
Data (69 bytes)

0000 7b 22 44 65 73 69 67 6e 22 3a 22 44 46 52 6f 62 {"Design":"DFRob
0010 6f 74 22 2c 22 6e 61 6d 65 22 3a 22 72 65 6c 61 ot","name":"rela
0020 79 34 22 2c 22 76 65 72 73 69 6f 6e 22 3a 22 56 y4","version":"V
0030 31 2e 30 55 22 2c 22 74 63 70 50 6f 72 74 22 3a 1.0U","tcpPort":
0040 32 30 30 30 7d 2000}

No. Time Source Destination Protocol Length Info
18897 81.948626 192.168.1.109 192.168.1.255 UDP 111 49154 → 6006 Len=69

Frame 18897: 111 bytes on wire (888 bits), 111 bytes captured (888 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: 00:df:38:37:ff:97 (00:df:38:37:ff:97), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 192.168.1.109, Dst: 192.168.1.255
User Datagram Protocol, Src Port: 49154, Dst Port: 6006
Data (69 bytes)

0000 7b 22 44 65 73 69 67 6e 22 3a 22 44 46 52 6f 62 {"Design":"DFRob
0010 6f 74 22 2c 22 6e 61 6d 65 22 3a 22 72 65 6c 61 ot","name":"rela
0020 79 34 22 2c 22 76 65 72 73 69 6f 6e 22 3a 22 56 y4","version":"V
0030 31 2e 30 55 22 2c 22 74 63 70 50 6f 72 74 22 3a 1.0U","tcpPort":
0040 32 30 30 30 7d 2000}

No. Time Source Destination Protocol Length Info
18955 82.948575 192.168.1.109 192.168.1.255 UDP 111 49154 → 6006 Len=69

Frame 18955: 111 bytes on wire (888 bits), 111 bytes captured (888 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: 00:df:38:37:ff:97 (00:df:38:37:ff:97), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 192.168.1.109, Dst: 192.168.1.255
User Datagram Protocol, Src Port: 49154, Dst Port: 6006
Data (69 bytes)

0000 7b 22 44 65 73 69 67 6e 22 3a 22 44 46 52 6f 62 {"Design":"DFRob
0010 6f 74 22 2c 22 6e 61 6d 65 22 3a 22 72 65 6c 61 ot","name":"rela
0020 79 34 22 2c 22 76 65 72 73 69 6f 6e 22 3a 22 56 y4","version":"V
0030 31 2e 30 55 22 2c 22 74 63 70 50 6f 72 74 22 3a 1.0U","tcpPort":
0040 32 30 30 30 7d 2000}

No. Time Source Destination Protocol Length Info
19070 83.948563 192.168.1.109 192.168.1.255 UDP 111 49154 → 6006 Len=69

Frame 19070: 111 bytes on wire (888 bits), 111 bytes captured (888 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: 00:df:38:37:ff:97 (00:df:38:37:ff:97), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 192.168.1.109, Dst: 192.168.1.255
User Datagram Protocol, Src Port: 49154, Dst Port: 6006
Data (69 bytes)

0000 7b 22 44 65 73 69 67 6e 22 3a 22 44 46 52 6f 62 {"Design":"DFRob
0010 6f 74 22 2c 22 6e 61 6d 65 22 3a 22 72 65 6c 61 ot","name":"rela
0020 79 34 22 2c 22 76 65 72 73 69 6f 6e 22 3a 22 56 y4","version":"V
0030 31 2e 30 55 22 2c 22 74 63 70 50 6f 72 74 22 3a 1.0U","tcpPort":
0040 32 30 30 30 7d 2000}

No. Time Source Destination Protocol Length Info
19183 84.948499 192.168.1.109 192.168.1.255 UDP 111 49154 → 6006 Len=69

Frame 19183: 111 bytes on wire (888 bits), 111 bytes captured (888 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: 00:df:38:37:ff:97 (00:df:38:37:ff:97), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 192.168.1.109, Dst: 192.168.1.255
User Datagram Protocol, Src Port: 49154, Dst Port: 6006
Data (69 bytes)

0000 7b 22 44 65 73 69 67 6e 22 3a 22 44 46 52 6f 62 {"Design":"DFRob
0010 6f 74 22 2c 22 6e 61 6d 65 22 3a 22 72 65 6c 61 ot","name":"rela
0020 79 34 22 2c 22 76 65 72 73 69 6f 6e 22 3a 22 56 y4","version":"V
0030 31 2e 30 55 22 2c 22 74 63 70 50 6f 72 74 22 3a 1.0U","tcpPort":
0040 32 30 30 30 7d 2000}

No. Time Source Destination Protocol Length Info
19280 85.948465 192.168.1.109 192.168.1.255 UDP 111 49154 → 6006 Len=69

Frame 19280: 111 bytes on wire (888 bits), 111 bytes captured (888 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: 00:df:38:37:ff:97 (00:df:38:37:ff:97), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 192.168.1.109, Dst: 192.168.1.255
User Datagram Protocol, Src Port: 49154, Dst Port: 6006
Data (69 bytes)

0000 7b 22 44 65 73 69 67 6e 22 3a 22 44 46 52 6f 62 {"Design":"DFRob
0010 6f 74 22 2c 22 6e 61 6d 65 22 3a 22 72 65 6c 61 ot","name":"rela
0020 79 34 22 2c 22 76 65 72 73 69 6f 6e 22 3a 22 56 y4","version":"V
0030 31 2e 30 55 22 2c 22 74 63 70 50 6f 72 74 22 3a 1.0U","tcpPort":
0040 32 30 30 30 7d 2000}

No. Time Source Destination Protocol Length Info
19362 86.948412 192.168.1.109 192.168.1.255 UDP 111 49154 → 6006 Len=69

Frame 19362: 111 bytes on wire (888 bits), 111 bytes captured (888 bits) on interface \Device\NPF_{93ADD185-2E4A-427C-80DF-6C8A5E837DAB}, id 0
Ethernet II, Src: 00:df:38:37:ff:97 (00:df:38:37:ff:97), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 192.168.1.109, Dst: 192.168.1.255
User Datagram Protocol, Src Port: 49154, Dst Port: 6006
Data (69 bytes)

0000 7b 22 44 65 73 69 67 6e 22 3a 22 44 46 52 6f 62 {"Design":"DFRob
0010 6f 74 22 2c 22 6e 61 6d 65 22 3a 22 72 65 6c 61 ot","name":"rela
0020 79 34 22 2c 22 76 65 72 73 69 6f 6e 22 3a 22 56 y4","version":"V
0030 31 2e 30 55 22 2c 22 74 63 70 50 6f 72 74 22 3a 1.0U","tcpPort":
0040 32 30 30 30 7d 2000}