Finisar Surveyor, User Manual

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10-83
Expert Features
Network Layer
10
ICMP Redirect
Counter
ICMP Redirect is a counter of all ICMP redirect errors over a period of time per
segment. A count of all redirect ICMP symptoms displays in the
Overview
counters
of Expert View. A threshold for this counter can be set in Expert Alarms.
The following types of ICMP redirect errors are counted:
Network Redirect, Host Redirect, Network Redirect for TOS, Host Redirect for
TOS, ICMP Redirect (catches all other Redirect errors).
Expert Symptom
ICMP Redirect is also an expert symptom, and has its own Diagnostic Details.
However, this expert symptom reflects only those redirect conditions which cannot
be assigned to one of the other redirect symptoms defined above.
ICMP Redirect events are automatically logged as expert symptoms. The
Symptom
Summary
field provides information about the IP addresses involved. For example:
Use Gateway [206.250.54.61] to reach [206.250.228.69] from
[206.250.228.11]. SA=[206.250.228.11] DA=[206.250.228.69]
Diagnostic Details
__________________________________________________________________
Problem Description:
An ICMP Redirect message has been sent.
__________________________________________________________________
Probable Cause(s):
1. If a router has a routing table problem, it may send this message.
2. A router may send this message if according to its (proper) routing tables it finds a
shorter path via a different router.
3. The source may have an incorrectly configured subnet mask.
4. The host (source) may have an old routing table.
__________________________________________________________________
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 redirect message is valid (no action required).