Finisar Surveyor manual Icmp Network Unreachable

Expert Features 10

Network Layer

ICMP Network Unreachable

Counter

ICMP Network Unreachable events are counted in the ICMP All Errors and the ICMP Destination Unreachable counters. A count of all destination unreachable ICMP symptoms and a count of all ICMP errors displays in the Overview counters of Expert View. A threshold can be set in Expert Alarms for all destination unreachable ICMP errors or for all ICMP errors.

Expert Symptom

ICMP Network Unreachable events are automatically logged as expert symptoms. The Symptom Summary field provides information about the IP addresses involved. For example:

[206.250.228.69] cannot be reached by [206.250.228.11].

SA=[206.250.228.11] DA=[206.250.228.69]

Diagnostic Details

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Problem Description:

An ICMP Destination Network Unreachable message has been sent.

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Probable Cause(s):

1.If a router has a routing table problem, it may send this message.

2.A host may send this message if a network is unreachable.

3.The source may have an incorrectly configured subnet mask.

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Recommended Action(s):

1.Check the routing tables of the router that this message was generated from.

2.Check the netmask configuration of the source.

3.Ignore this message if the network is truly unreachable (no action required).

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