[EXT_EP-11191] TCP communication blocked intermittently with multicast traffic in the background Created: 20/Jun/23  Updated: 20/Jun/23  Resolved: 20/Jun/23

Status: Declined
Project: Embedded Software & Tools
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Bug Priority: High
Reporter: TI User Assignee: TI User
Resolution: Won't Fix Votes: 0
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified

Product: Linux Core SDK
Internal ID: LCPD-34608
Found In Release: 08.06.00
Affected Platform/Device: j7200-evm
Decline Reason: Issue is determined to be due to an incorrect .network file configuration and this is unrelated to the driver or hardware.

 Description   

When multicast traffic is pushed in the background of a VLAN aware bridge, Sporadic connection issues with tcp communication initiated from the SOC.

Steps:

  1. On a switch mode setup with bridge configured and a vlan configured on top of it, add a multicast route
    1. ip route add 239.255.42.99 via <ip-addr-of-eth1.73> dev eth1.73
  2. Start a iperf multicast server on the PC
    1. iperf -s -B 239.255.42.99 -u
  3. Start an iperf client on SoC in Background

    1. iperf -c 239.255.42.99 -u -T 32 -t 100 -b 100M &
  4. Now try any tcp communication (ssh/wget/iperf3), it will fail sporadically

See attached logs : 

 _____                    _____           _         _   
|  _  |___ ___ ___ ___   |  _  |___ ___  |_|___ ___| |_ 
|     |  _| .'| . | . |  |   __|  _| . | | | -_|  _|  _|
|__|__|_| |__,|_  |___|  |__|  |_| |___|_| |___|___|_|  
              |___|                    |___|            Arago Project j7200-evm ttyS2Arago 2021.09 j7200-evm ttyS2j7200-evm login: root
root@j7200-evm:~# iperf -c 239.255.42.99 -u -T 32 -t 100 -b 200M &
[1] 1049
root@j7200-evm:~# ------------------------------------------------------------
Client connecting to 239.255.42.99, UDP port 5001
Sending 1470 byte datagrams
Setting multicast TTL to 32
UDP buffer size:  224 KByte (default)
------------------------------------------------------------
[  3] local 192.168.5.135 port 60073 connected with 239.255.42.99 port 5001
ssh user@192.168.5.100 "echo 0 > /home/user/test"ssh: Connection to user@192.168.5.100:22 exited: Connect failed: Network is unreachable
root@j7200-evm:~# 
root@j7200-evm:~# 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 1 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 2 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 3 > /home/user/test"ssh: Connection to user@192.168.5.100:22 exited: Connect failed: Network is unreachable
root@j7200-evm:~# 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 4 > /home/user/test"ssh: Connection to user@192.168.5.100:22 exited: Connect failed: Network is unreachable
root@j7200-evm:~# 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 5 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 6 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 7 > /home/user/test"ssh: Connection to user@192.168.5.100:22 exited: Connect failed: Network is unreachable
root@j7200-evm:~# 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 8 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 9 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 10 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 11 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 12 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 13 > /home/user/test"ssh: Connection to user@192.168.5.100:22 exited: Connect failed: Network is unreachable
root@j7200-evm:~# 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 14 > /home/user/test"ssh: Connection to user@192.168.5.100:22 exited: Connect failed: Network is unreachable
root@j7200-evm:~# 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 15 > /home/user/test"ssh: Connection to user@192.168.5.100:22 exited: Connect failed: Network is unreachable
root@j7200-evm:~# 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 16 > /home/user/test"ssh: Connection to user@192.168.5.100:22 exited: Connect failed: Network is unreachable
root@j7200-evm:~# [ ID] Interval       Transfer     Bandwidth
[  3]  0.0-100.0 sec  2.36 GBytes   203 Mbits/sec
[  3] Sent 1723056 datagrams
[  133.692750] Initializing XFRM netlink socket
[  136.588425] Bridge firewalling registered
[  138.760633] process 'docker/tmp/qemu-check134822957/check' started with executable stack
[1]+  Done                    iperf -c 239.255.42.99 -u -T 32 -t 100 -b 200M
root@j7200-evm:~# ssh user@192.168.5.100 "echo 17 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 18 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 19 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 20 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 21 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 22 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 23 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 24 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 25 > /home/user/test"
user@192.168.5.100's password: 
root@j7200-evm:~# ssh user@192.168.5.100 "echo 26 > /home/user/test"

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