Extreme switch disconnects frequently from ODL controller

[Leonardo3]

Hi, I'm using this switch X460G2-48p-10G4 (Stack) with openflow mode enabled and connected to my opendaylight controller as "primary":

Controller : Primary
Status : ACTIVE
Datapath ID : 00000204969ac040
VR : VR-Default
Mode : out-of-band Active
Target : tcp:172.20.0.40:6633
Uptime(secs) : 845

It happens very often that the tcp connection to the controller is being closed and reopened multiple times.

Is there any known issue on the switch?
Any useful diagnostic I can enable on the switch?
The log is not saying anything useful.

thank you
Leonardo

[Karthik_Mohando]

Leonardo,

I would suggest to open up a case with TAC.

[Karthik_Mohando]

Leonardo,

To start with. did you get any insight form the "show log" , you can check the port where the controller is connected for any congestion, errors or flaps.

"show ports congestion"
"show ports rxerrors"
"show ports txerrors"

Also check for any issues in the counter part if none is found then i would suggest to open up case case with TAC.

[Leonardo3]

I cannot find anything interesting in the log files, no mention to openflow disconnection events. From ODL side, I can see the following exception:

2017-07-13 04:38:50,495 | WARN | entLoopGroup-5-6 | OFFrameDecoder | 265 - org.opendaylight.openflowjava.openflow-protocol-impl - 0.8.4.SNAPSHOT | Unexpected exception from downstream.
io.netty.channel.unix.Errors$NativeIoException: syscall:read(..) failed: Connection reset by peer
at io.netty.channel.unix.FileDescriptor.readAddress(..)(Unknown Source)
2017-07-13 04:38:50,496 | WARN | entLoopGroup-5-6 | OFFrameDecoder | 265 - org.opendaylight.openflowjava.openflow-protocol-impl - 0.8.4.SNAPSHOT | Closing connection.
2017-07-13 04:38:50,496 | INFO | entLoopGroup-5-6 | SystemNotificationsListenerImpl | 274 - org.opendaylight.openflowplugin.impl - 0.3.4.SNAPSHOT | ConnectionEvent: Connection closed by device, Device:/172.20.0.19:58045, NodeId:openflow:19706488169

According to the above log, it seems the device is closing the connection.
Every since the switch is sending a OFPT_ECHO_REQUEST message and the controller is quickly answering with OFPT_ECHO_REPLY. After this message exchange, the connection goes down.
Any thoughts?

thank you
Leonardo