Why do SZ shows us "Client session expired"?

[hyosang_choi]

Hi.

Sometimes we find event log as "Client session expired" on web-ui of SZ100 .

A security type of the SSID is wpa2-psk-aes.

I know that type of psk don't have session-timeout.

Why do SZ show us the message?

Regards.

[michael_brado]

Was it from an AP that the client has roamed away from?

[hyosang_choi]

The log is shown regardless of roaming.

Duration is exacty 2days.

[michael_brado]

Has anyone reported any kind of problem?  2 days sounds like a lengthy session timeout set on the WLAN.

[hyosang_choi]

It's odd.

Recently In hospitality some customer deployed IOT device.

The devices is connecting 365days to WIFI.

Sometimes, after the device is disconnected by the deauth as "session expired" , don't connect to wifi again.

I also know though it's disconnected, the device have to re-conntected to WIFI automatically.

But this timeout is very odd because wlan type is open or psk not wispr having session timeout.

See below, the device is connected to WIFI very normally.  

Session duration is exactly 2days.

Wlan type is open and no encryption.

In this case the AP should not have session-timeout.

See below log.

We can find "deauthenticated due to session timeout".

And duration is about "172800 sec" exactly "sessionDuration"="172803".

Sep 13 03:46:22 Hospitality-AP local1.info sessionMgr[554]: handle_scg_del_ue_ctx_req:1074 UE[5c:cf:7f:cc:0f:8d][wlan7]msg->msg.apDelCtxtReq.sessTerCause=3
Sep 13 03:46:22 Hospitality-AP daemon.info hostapd: wlan7: STA 5c:cf:7f:cc:0f:8d IEEE 802.11: wlan7: IEEE 802.11: ***DEBUG*** deauthenticated due to session timeout
Sep 13 03:46:22 Hospitality-AP daemon.info hostapd: @@208,clientSessionExpiration,"apMac"="xx:xx:xx:xx:xx:xx","clientMac"="5c:cf:7f:cc:0f:8d","ssid"="WLAN-open","bssid"="xx:xx:xx:xx:xx:xx","userId"="","wlanId"="12","iface"="wlan7","tenantUUID"="839f87c6-d116-497e-afce-aa8157abd30c","apName"="Hospitality-AP","clientIP"="10.0.4.31","vlanId"="3002","radio"="b/g/n","encryption"="None","hostname"="HomeMate_device","firstAuth"="1536637579","associationTime"="0","ipAssignTime"="1536637582","disconnectTime"="1536810382","sessionDuration"="172803","disconnectReason"="2","rxFrames"="3579","rxBytes"="493624","txFrames"="165603","txBytes"="8626471","peakRx"="48252","peakTx"="14504","rssi"="63","receivedSignalStrength"="-42"
Sep 13 03:46:22 Hospitality-AP daemon.info hostapd: wlan7: STA 5c:cf:7f:cc:0f:8d IEEE 802.11: wlan7: IEEE 802.11: hostapd_stats_upd_client, username=, disconReason=2 
Sep 13 03:46:22 Hospitality-AP daemon.info hostapd: IEEE 802.11: hostapd_stats_send2collectd, send data len=216
Sep 13 03:46:22 Hospitality-AP daemon.err collectd[4119]: client_upd_handler, receive updSta data with len 216 
Sep 13 03:46:22 Hospitality-AP local1.err sessionMgr[554]: sm_handle_ipc_ue_context_update:417 No UE context found
Sep 13 03:46:22 Hospitality-AP local1.info sessionMgr[554]: handle_ue_state_change:380 UE[5c:cf:7f:cc:0f:8d][wlan7]UE state changed from [uninitialized] to [deauth]
Sep 13 03:46:22 Hospitality-AP daemon.warn Eved: STA-DISASSOC-REASON [domlme(),7144,domlme] 5c:cf:7f:cc:0f:8d rx_rssi=47,ack_rssi=0,reason=2,freq=2412,chan=1,rx pkt,byte;tx pkt,byte=(3579,493624,165603,8626471)
Sep 13 03:46:22 Hospitality-AP daemon.info hostapd: wlan7: STA 5c:cf:7f:cc:0f:8d IEEE 802.11: wlan7: IEEE 802.11: disassociated



Also see below log. That's a log after reconntected.

There is no time-out such as "sessionTimeout=0".

Sep 13 03:46:26 Hospitality-AP local1.info sessionMgr[554]: handle_ue_state_change:380 UE[5c:cf:7f:cc:0f:8d][wlan7]UE state changed from [uninitialized] to [session_active]
Sep 13 03:46:26 Hospitality-AP local1.info sessionMgr[554]: build_and_send_scg_ue_ctx_create:490 UE[5c:cf:7f:cc:0f:8d][wlan7]apCrtCtxtReq.ueCtxtState=1 dot11State=1 wlanid=12 sessStartTime=1536810383 vlan=3002 sessionTimeout=0

The device will be diconnected to WIFI after 2 day.

Does anyone know why this works?

Regards.