Hardware fault troubleshooting – Amer Networks E5Web GUI User Manual
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information to a file on the Clavister Security Gateway.
These output files are placed into the cOS Core root directory and the file name is specified in the
pcapdump command line, usually with a filetype of .cap. The name of output files must follow
certain rules which are described below. Files can be downloaded to the local workstation using
Secure Copy (SCP) (see Section 2.1.6, “Secure Copy”). A list of all files in the cOS Core root directory
can be viewed by issuing the ls CLI command.
The -cleanup option will erase the files so cleanup should only be done after file download is
complete.
Output File Naming Restrictions
The name of the file used for pcapdump output must comply with the following rules:
•
Excluding the filename extension, the name may not exceed 8 characters in length.
•
The filename extension cannot exceed 3 characters in length.
•
The filename and extension can only contain the characters A-Z, 0-9, "-" and "_".
Combining Filters
It is possible to use several of these filter expressions together in order to further refine the
packets that are of interest. For example we might want to examine the packets going to a
particular destination port at a particular destination IP address.
Compatibility with Wireshark
The open source tool Wireshark (formerly called Ethereal) is an extremely useful analysis tool for
examining logs of captured packets. The industry standard .pcap file format used by pcapdump
with its -write option means that it is compatible with Wireshark.
For more complete information about this topic, see
2.5.4. Hardware Fault Troubleshooting
It may be the case that operational problems are caused by a problem with the hardware
platform and not cOS Core. For this reason, the CLI command selftest is provided to perform tests
on various aspects of hardware functioning.
Warning: Do NOT conduct tests with live traffic!
It is important to remember that the selftest command should not be used on a system
that is carrying live traffic. The command can cause connections and associated data to
be lost and the test results themselves will be unreliable.
Preparing Hardware
To ensure the complete reliability of any selftest, it is recommended to take a complete backup
of the current configuration and reset the hardware unit to the base configuration as well as
having the unit disconnected from any networks.
This is also true for units in an HA cluster. The cluster should be broken up into two separated
Chapter 2: Management and Maintenance
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