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RoomAlert 11E sensors randomly display "No Data"



I have several sensors monitoring a RoomAlert Model 11E. Randomly, and in no particular order, the sensors alert with "No Data" and the following error message:

"No response (check: firewalls, routing, snmp settings of device, IPs, SNMP version, community, passwords etc) (SNMP error # -2003)"

The sensor recovers after a few minutes and then shortly after a different sensor alerts. I tried adjusting the SNMP time out period from the default 5 seconds to 30 seconds but this appeared to have no effect. SNMP V1, Port 161, SNMP Timeout is 30 seconds. My probe and device are behind a Cisco router and switch.

server-2008-r2 snmp snmp-error#2003

Created on Jan 27, 2015 9:44:31 PM

1 Reply



Hi Cale,

The SNMP error 2003 indicates that your PRTG server or your remote probe cannot establish a connection to the target device. As this error just occurs from time to time, your credentials (the community string) seems to be valid. For me it looks like an issue with the load of either the PRTG server or any device inbetween the server and the target device.

Please check the Probe Health Sensor if there is any delay for the SNMP requests or any other unusual value.

Best regards

Created on Jan 29, 2015 12:31:11 PM by  Felix Saure [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.