SNMP Driver

[Rolf.Appel]

Hello,

I am using SNMP to supervise the status of external devices and their interfaces (Ethernet, DSL, …).
Agent-Parameters are:
Protocol: v2
Timeout: 300 (i.e. 3 seconds)
Retries: 5
Method: Polling

My expectation was that connection state (DPE _x_SNMPAgent_xxx.Status.ConnState) is set to FALSE (i.e. error) only after all 5 Retries have failed.

But I observe very often that connection state is set to FALSE and mostly after 0 or 3 or 6 seconds (which is n times the Timeout) the connection state comes back to TRUE (i.e. OK). The connection state is used via DP-Function to alarm a device DPE and so the plant operator receives many useless alarms.

Is my expectation wrong, means even the first or second poll failure results in a connection state failure?
Or is a special configuration necessary to enable my expectation?

Thanks in advance for your answer.

Rolf Appel

[automation]

What OS?

I've seen similar things in Red Hat. Same project on Windows did not throw errors.

[Rolf.Appel]

OS is Windows Server 2012 R2.
WinCC OA 3.14

[Gertjan van Schijndel]

Try the element '.Status.Timeout'.