Station Drop

Hi

Sometimes we get notification in cnMaestro (On-premises 1.6.0.-r18) Station Drop for AP. What does it mean?

Or is there any document/list of all possible errors that are shown in cnMaestro, so we can analyse on our own what are the reasons for alarms?

Thank you.

STA_DROP means a device (SM) has stopped communicating with the AP

STA_REG means a device (SM) has registered and is communicating with the AP

You should also see STATUS events indicating the units are offline and online accordingly.  These two are connection status to Maestro.  As for a list of possible alarms/events, I don't remember there being one.  However, the message field will clue you in to the event/alarm.

Hope this helps.

1 Like

Thank you for your explanation, I don't how I missed your reply.


What does this error means?

STA_REJECT

Regards

EDIT: Is there any guide or list, where we can find all possible errors for cnMaestro and for ePMP devices, so we can troubleshoot easier?

STA_REJECT means the ePMP AP has rejected the SM association with the AP . This can be due to mismatch in authentication method or Frequency or bandwidth etc...,

We will look more deeply in this, but as I see for now, a few minutes later SM is accepted without problems wihout changing configuration.

Let's say in this example from today:

SM disconnected from AP and in the same second we get reject status and a minute later registered.

Could you explain me the events what probably happened, so we can understand whole picture?

Thanks

Hi ,

Initially you got STA_REJECT from an SM . From the event we are not sure which SM is this as MAC address is not being captured as part of this event. But since the association parameters did not match the Station_Registered did not happen. 

Then you got STA_DROP from an SM with a particular MAC as you can see in the event Message. This is from an SM already rgistered to the AP. The rejection can happen due to many RF related reasons like RSSI of uplink and downlink, SNR , Quality and capacity of the downlink. Interference can also play a major role. 

Then finally you got the Station_Registered from the same SM as earlier dropped SM after nearly 1 minute . This may be due to again the same RF factors might have been improved and the SM was able to associate with the AP. 

In my case also out of two SMs connected to ePMP 2000 AP one is stable as it is connected through RF cables and all. The other SM is not connected trhough RF cables and is an integrated SM and gets disconnected and connected multiple times due to RF interference from other wifi devices.

Here i am attaching the screenshots of my SMs registered to AP and their RF stats in Monitor->Wireless page of the device GUI.

Also i am attaching the events GUI from cnMaestro for the AP where you can see the events you are asking coming in different orders multiple times. I marked events for the SM getting dropped and registered in RED.

For better understanding i just rebooted my AP . Please find below attached screenshot showing the sequence of events for the AP and also the device logs indicating the messages for STA DROP , REJECT and Register.

Device System Log :-

Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: send_trap_info: Wake up JSON Object: [{"msgType": 699, "eId": "STA_REJECT", "eTime": 1521193761}]
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: ping call back
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: PING_DATA: len=68 msg [{"Message":"ping from device agent", "Pid": "2898", "PongLoss": "0"}]
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: service_ping: Ping enqueued
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: send new ping after 24 seconds
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: LWS_CALLBACK_CLIENT_WRITEABLE
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: LWS_CALLBACK_CLIENT_WRITEABLE
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb: MSG [0x7f85f3f4] len=1
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb:MSG TYPE = 1
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: Trap data received: name STA_DROP timestamp 1521193761 mac DC:9F:DB:4C:7B:14 status 0 msg [COMMUNICATION LOST]
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: send_trap_info: Wake up JSON Object: [{"msgType": 699, "eId": "STA_DROP", "eTime": 1521193761, "varPayload": {"mac": "DC:9F:DB:4C:7B:14"}}]
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: LWS_CALLBACK_CLIENT_WRITEABLE
Mar 16 15:19:21 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: Received Pong message from cnMaestro
Mar 16 15:19:25 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb: MSG [0x7f85f3f4] len=1
Mar 16 15:19:25 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb:MSG TYPE = 1
Mar 16 15:19:25 ePMP2k-Production DEVICE-AGENT[2898]: Trap data received: name SYS_UP timestamp 1521193765 mac (null) status 1 msg [The Initialization State]
Mar 16 15:19:25 ePMP2k-Production DEVICE-AGENT[2898]: send_trap_info: Wake up JSON Object: [{"msgType": 699, "eId": "SYS_UP", "eTime": 1521193765}]
Mar 16 15:19:25 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: LWS_CALLBACK_CLIENT_WRITEABLE
Mar 16 15:19:46 ePMP2k-Production DEVICE-AGENT[2898]: ping call back
Mar 16 15:19:46 ePMP2k-Production DEVICE-AGENT[2898]: PING_DATA: len=68 msg [{"Message":"ping from device agent", "Pid": "2898", "PongLoss": "0"}]
Mar 16 15:19:46 ePMP2k-Production DEVICE-AGENT[2898]: service_ping: Ping enqueued
Mar 16 15:19:46 ePMP2k-Production DEVICE-AGENT[2898]: send new ping after 27 seconds
Mar 16 15:19:46 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: LWS_CALLBACK_CLIENT_WRITEABLE
Mar 16 15:19:46 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: Received Pong message from cnMaestro
Mar 16 15:19:49 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb: MSG [0x7f85f3f4] len=1
Mar 16 15:19:49 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb:MSG TYPE = 1
Mar 16 15:19:49 ePMP2k-Production DEVICE-AGENT[2898]: Trap data received: name STA_REG timestamp 1521193789 mac DC:9F:DB:4C:7B:14 status 0 msg [(null)]
Mar 16 15:19:49 ePMP2k-Production DEVICE-AGENT[2898]: send_trap_info: Wake up JSON Object: [{"msgType": 699, "eId": "STA_REG", "eTime": 1521193789, "varPayload": {"mac": "DC:9F:DB:4C:7B:14"}}]
Mar 16 15:19:49 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: LWS_CALLBACK_CLIENT_WRITEABLE
Mar 16 15:19:51 ePMP2k-Production kernel: [ 138.980000] SM[dc:9f:db:4c:7b:14] aid=2 disassociated. Reason: COMMUNICATION LOST
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb: MSG [0x7f85f3f4] len=1
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb:MSG TYPE = 1
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: Trap data received: name STA_REJECT timestamp 1521193791 mac DC:9F:DB:4C:7B:14 status 0 msg [COMMUNICATION LOST]
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: send_trap_info: Wake up JSON Object: [{"msgType": 699, "eId": "STA_REJECT", "eTime": 1521193791}]
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: LWS_CALLBACK_CLIENT_WRITEABLE
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb: MSG [0x7f85f3f4] len=1
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: event_rx_cb:MSG TYPE = 1
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: Trap data received: name STA_DROP timestamp 1521193791 mac DC:9F:DB:4C:7B:14 status 0 msg [COMMUNICATION LOST]
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: send_trap_info: Wake up JSON Object: [{"msgType": 699, "eId": "STA_DROP", "eTime": 1521193791, "varPayload": {"mac": "DC:9F:DB:4C:7B:14"}}]
Mar 16 15:19:51 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: LWS_CALLBACK_CLIENT_WRITEABLE
Mar 16 15:20:02 ePMP2k-Production DEVICE-AGENT[2898]: da_alive_cb: Kicking the DA watchdog
Mar 16 15:20:14 ePMP2k-Production DEVICE-AGENT[2898]: ping call back
Mar 16 15:20:14 ePMP2k-Production DEVICE-AGENT[2898]: PING_DATA: len=68 msg [{"Message":"ping from device agent", "Pid": "2898", "PongLoss": "0"}]
Mar 16 15:20:14 ePMP2k-Production DEVICE-AGENT[2898]: service_ping: Ping enqueued
Mar 16 15:20:14 ePMP2k-Production DEVICE-AGENT[2898]: send new ping after 16 seconds
Mar 16 15:20:14 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: LWS_CALLBACK_CLIENT_WRITEABLE
Mar 16 15:20:14 ePMP2k-Production DEVICE-AGENT[2898]: callback_websocket: Received Pong message from cnMaestro

Events Screenshot :-

The conclusion is once the STA DROP happens either due to communication lost or RF conditions , the next events are Register and REJECT . If the AP and SM association parameters are matching the Register will get success otherwise the AP will send the STA_REJECT message. Here as the AP has just come up and when the SM asked for registration it was rejected saying communication lost. The SM made another attempt and also was rejected due to communication lost itself and in the final register attempt SM was able to register to AP. please check the events for the device mac ending with 7B:14 . The top 4 events will explain this .

These events sequence can be seen in both the screenshot and the logs pasted in the post.

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Thank you for this informations, they are very helpful.