Hi ReneKn,

Thank you for posting in SOTI Central.

An interesting issue to read here. Ideally, you need to raise a Support Case and then provide DS Verbose Logs along with the PKCtrlSv.log. We would then try to identify the problem within the logs, one problem could be a Pulse Timeout problem for example. But we would only be guessing without the logs.

What I suggest you do is perform a fresh enrollment of an affected device with the latest agent (you may need to rebuild with the newest version with the Add Device Rule), then reproduce the problem and collect those logs. 

Additionally, if it's possible. I suggest setting up WireShark in a controlled environment, this might be helpful in understanding the issue further. For example, it could be an SSL Handshake problem.

If you can easily reproduce the problem, then you can test a few areas of interest. For example, change your network to a 4G network? Does the newest agent help? Is it reproducible in other environments?

Regards,

thanks für your answer!! 

oo yes thats true, I have a lot of experience with MC, but i have never see this behavior.

what exactly do you mean by Pulse Timeout.. ?

i use the newes agent for the enrollment.

WireShark is a good idiea...!!

we use only wlan on this devices and the connection is stable.

PKCtrlSv.log

2020/11/17 13:25:09.000(0xadc11f5e): EVENT: SCC: Connecting to ws003908.schaeffler.com, port=5494
2020/11/17 13:25:09.000(0xadc11f5e): EVENT: SSL: TargetName: 9E320EBE.ws003908.schaeffler.com
2020/11/17 13:25:10.000(0xadc11f5e): ERROR: Socket: The connection has been gracefully closed
2020/11/17 13:25:10.000(0xadc11f5e): EVENT: SCC: Failed to connect to ws003908.schaeffler.com, port=5494, error=1
2020/11/17 13:25:10.000(0xadc11f5e): DEBUG: WriteMCConnectionStatus: Status = 2
2020/11/17 13:25:10.000(0xadc11f5e): DEBUG: WriteMCConnectionStatus: Registry write SUCCESS
2020/11/17 13:25:10.000(0xadc11f5e): EVENT: SCC: Connecting to 10.160.172.13, port=5494
2020/11/17 13:25:10.000(0xadc11f5e): EVENT: SSL: TargetName: 9E320EBE.10.160.172.13
2020/11/17 13:25:12.000(0xadc11f5e): ERROR: Socket: The connection has been gracefully closed
2020/11/17 13:25:12.000(0xadc11f5e): EVENT: SCC: Failed to connect to 10.160.172.13, port=5494, error=1

2020/11/17 13:25:53.000(0xec6616d2): ERROR: CerDelete: Certificate (Issuer='MobiControl Root CA', SN='23dea345b0b57ef5') was not found.
2020/11/17 13:25:52.000(0xadc11f5e): DEBUG: ProcessMessage: type 24
2020/11/17 13:25:52.000(0x8de61962): ERROR: Schedule: Reload
2020/11/17 13:25:52.000(0xec6616d2): DEBUG: CMemComm::Write: this 198DE410, dwBufLen 8, m_bServer 1, pMem->m_DataLen 0
2020/11/17 13:25:52.000(0xadc11f5e): ERROR: Failed waiting ACK

this is all what i found.. 

Hi ReneKn,

Server Side:

Pulse Timeout is used by DS to keep the device status up to date. This value indicates how frequently the DS sends the pulse to the device to confirm the device is online. This setting can be changed in MCAU > Deployment Server > "Send Test Messages to Devices Every". Under heavy load, the DS is extremely busy and cannot send out such a frequent pulse leading to pulses being delayed. The device will still expect the pulse in 60 seconds, as defined by the parameter, and device disconnection can occur if it doesn’t detect one. 

Client-Side (Agent):

The same principle to devices too, there are ways of modifying it. But it applies mainly to Android deployments.

Regarding your issue, can you double-check that your DS Certificate Binding matches the FQDN of the DS? TargetName: 9E320EBE.ws003908.schaeffler.com jumps out to me. Can you also double-check an affected device and then check the PDB.INI and MCSETUP.ini, do you see any problems with FQDN's not matching up?

On top of that, this issue is reproducible on a newly enrolled device? Is the issue easily reproducible in general too?

Regards,

Have you also upgraded  (i.e. generated) your MobiControl root certificate when upgrading your MobiControl server to v14.5.4?

What is the length (i.e. the number of bits)  of your SSL certificate bind to the domain ws003908.schaeffler.com?  Is it a single domain or wild-card certificate?