Analyzing Captured Packets; Extended Keepalive; Description - Avaya G350 Maintenance Manual

Monitoring

Extended keepalive

Analyzing captured packets

Analyze the captured packets using the following steps:
•
Stop the packet sniffing service.
•
Upload the capture file to a remote server.
•
Analyze the capture file.
Stopping the packet sniffing service
You stop the packet sniffing service using the
to upload a capture file.
NOTE:
The
Uploading the capture file
Once the packet sniffing service is stopped, upload the capture file to a remote server for analysis. Use
one of the following commands to upload the capture file:
•
copy capture-file ftp
•
copy capture-file tftp
•
copy capture-file scp
Analyzing the capture file
The uploaded capture file is in libpcap format and can therefore be viewed using the industry standard
Ethereal application. The latest version of Ethereal for Windows, Linux, UNIX, and other platforms can
be downloaded from http://www.ethereal.com.
Extended keepalive

Description

Keepalive is a mechanism for determining if a certain IP address is reachable. The source interface sends
test packets (ping) and waits for a response. If no response is received after a certain number of tries, the
connection is declared to be down.
Normal keepalive is sufficient for testing the status of a direct connection between two points. However,
in many situations the system needs to know the status of an entire path in order to ensure that packets
can safely traverse it.
Extended Keepalive is a mechanism that reports on the status of an IP address and its next hop. The
destination interface is only declared to be alive if the next hop is also reachable. This feature is critical
for mechanisms such as policy-based routing that must guarantee service on a particular path.
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capture stop
capture stop command is not saved in the startup configuration file.
command. You must stop the service in order
Maintenance of the Avaya G350 Media Gateway
June 2004