Finisar Surveyor, User Manual

Page: 285 / 454

10-81
Expert Features
Network Layer
10
ICMP Port Unreachable
Counter
ICMP Port 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 Port Unreachable events are automatically logged as expert symptoms. The
Symptom Summary
field provides information about the IP addresses involved. For
example:
Port=22 on [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 Port 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 port 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 port is truly unreachable (no action required)
Ex: SNMP port connection requests.