Expert Features 10

Network Layer

ICMP Time Exceeded

Counter

ICMP Time Exceeded events are counted in the ICMP All Errors counter. A count of all ICMP errors displays in the Overview counters of Expert View. A threshold can be set in Expert Alarms for all ICMP errors.

Expert Symptom

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

Sent by Gateway [206.250.228.61] to [206.250.228.11] when

forwarding to Destination [206.250.228.69].

SA=[206.250.228.11] DA=[206.250.228.69]

Diagnostic Details

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Problem Description:

An ICMP Time Exceeded message has been sent.

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Probable Cause(s):

1.A router may send this message if it encounters an IP packet with a TTL value of 0.

2.The source may have an incorrectly configured subnet mask, causing longer hops.

3.The routing tables may be incorrect on the source.

4.A host may send this message if it cannot reassemble the fragments (due to

missing fragments) on time.

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Recommended Action(s):

1.Check the routing tables of the source.

2.Check the netmask configuration of the source.

3.Check for missing IP fragments.

4.May need to upgrade your router or host.

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Finisar Surveyor manual Icmp Time Exceeded