3.1.6 Polling protocols
You can prevent NNMi from using SNMP or ICMP in portions of your network (for example, when firewalls in your infrastructure prohibit ICMP or SNMP traffic).
Disabling ICMP traffic to the devices in an area of the network has the following results in NNMi:
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The optional auto-discovery rule Ping sweep feature cannot locate additional nodes in that region of your network. All nodes must either be seeded or available through answers to MIB object requests, such as neighbor's ARP cache, Cisco Discovery Protocol (CDP), or Extreme Discovery Protocol (EDP). Wide area network devices might be missed unless you seed every one of them.
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The State Poller cannot monitor devices that are not configured to respond to SNMP requests.
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Operators cannot use Actions > Node Access > Ping to check device reachability during troubleshooting.
Disabling SNMP traffic to the devices in an area of the network has the following results in NNMi:
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Discovery cannot gather any information about the devices except that they exist. All devices receive the No SNMP device profile.
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Discovery cannot find additional neighboring devices through queries. All devices must be directly seeded.
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Discovery cannot gather connectivity information from the devices, so they appear unconnected on NNMi maps.
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For devices with the No SNMP device profile, the State Poller respects the defaults of monitoring that device using only ICMP (ping).
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The State Poller cannot gather component health or performance data from the devices.
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The Causal Engine cannot contact the devices to perform neighbor analysis and locate the root cause of incidents.