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Erroneous/false alarms




More recently, the program alarms works is not satisfactory. There was a lot of false alerts. I have 400 active sensors, and every two to three hours I'm losing connect with them. At the same time with the network devices that I monitoring all is ok.

I get a message such:

  • Warning, Request timed out (ICMP error # 11010)
  • No response (check: firewalls, routing, snmp settings of device, IPs, SNMP version, *community, passwords etc) (SNMP error # -2003)

My configs are:

  • SNMP Timeout (sec.) - 15
  • SNMP Delay (ms) - 3

What is the problem?


alarms falsealarms snmp

Created on Jun 16, 2012 9:21:04 PM

1 Reply



Both error messages clearly say, that the PRTG probe has network connectivity problems with the devices for ICMP (=PING) and SNMP.

You should check the network for packet loss, short connections drops, etc. E.g. using a PING sensor with 50 packets, that will display the packet loss rate for ICMP. Also, using the QoS sensor you can find out if there are network problems.

It is very very unlikely that this is a software problem of PRTG. Actually, this is what monitoring is for: Finding network problems :-)

Created on Jun 19, 2012 8:56:51 AM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6

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