Port data change notification - line delay mismatch

[aqwe]

We have in field unexpected alarms with different devices. Some devices send in case of using FSU very often after a power cycle an alarm "Port data change notification - line delay mismatch". After few milliseconds the alarm disappers. We see this only by some devices and we think it differs in the used technology inside the devices.
Is there any specified delay time for this alarm specified? What are possible suggestions to improve the device behaviour for more robustness?

[llindemann]

We have in field unexpected alarms with different devices. Some devices send in case of using FSU very often after a power cycle an alarm "Port data change notification - line delay mismatch". After few milliseconds the alarm disappers. We see this only by some devices and we think it differs in the used technology inside the devices.
Is there any specified delay time for this alarm specified? What are possible suggestions to improve the device behaviour for more robustness?

Hi there are two similarly named diagnosis object, both linked to the AlarmType "port data change notification":

• one is the "Datatransmission impossible - line delay mismatch"
  This one is raised if you configured to observe line delay & line delay was not able to be measured or is out of the expected range.

• the second one is "Remote mismatch - peer line delay mismatch".
  This one is raised if the difference of the locally measured line delay and remote one exceed threshold.

There is no delay defined devices shall wait before emitting the diagnosis alarm. To prevent transient diagnosis states to be reported alarms should only be raised only if the peer is up an running and sends LLDP frames.

Assuming you're facing the first one it seems that the diagnosis is publish either to early (local measurement is not jet stable) or the remote is not jet run the delay responder.

What did mean by "improve device behavior for more robustness? " Did you face issues besides the transient diagnosis entries? Are you able to change device firmware?

[aqwe]

We have in field unexpected alarms with different devices. Some devices send in case of using FSU very often after a power cycle an alarm "Port data change notification - line delay mismatch". After few milliseconds the alarm disappers. We see this only by some devices and we think it differs in the used technology inside the devices.
Is there any specified delay time for this alarm specified? What are possible suggestions to improve the device behaviour for more robustness?

We got the AlarmType "port data change notification" - "Datatransmission impossible - line delay mismatch" and also some times later "Remote mismatch - peer line delay mismatch".

In the wireshark logging there are no LLDP frames recorded.

Our first impression was, that this is a sporadic issue. After deeper analyzed wireshark logging it seems that it's an issue between two network devices.

With "improve device behavior for more robustness" we mean face issues besides the transient diagnosis entries. We are not able to change device firmware but we can ask our supplier.