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Downloading Custom Packet Filters 317
Downloading
Custom Packet
Filters
Downloading a packet filter to the Switch 4007 is a two-step process.
You log in to the EME and enter the
download module
command with a
file type of
filter
. The EME does a TFTP file transfer and sends the file to
the module. The module places the file in a temporary buffer. You then
connect to the module and enter the
bridge packetFilter load
command to store the filter on the module. This command is not
interactive because the module knows where to find the filter.
Because this is a two-step process there are restrictions placed on each
step of the process. After you download a filter to a module, you cannot
download a second filter until the first filter is stored. A module only has
one buffer to hold one unstored filter at a time. If you attempt a second
download, an error message is displayed and the transfer is aborted. If
you download a filter file and then do not perform the second part of the
process to store the filter, the filter file will be lost upon reset of the
module. The filter is stored in a buffer on the module and not in NVRAM
until it is loaded. It is not saved when a module is reset.
Setting Up Your
Environment
Before you attempt to load a Filter Builder predefined or custom filter on
a device, you must have the following running on your PC:
■
The latest version of Filter Builder.
Filter Builder is part of the Web Management suite of applications on
the Switch 4007 software CD. See the
Web Management User Guide
for procedures and software prerequisites.
■
A TFTP server application.
This application must be set up with access to the appropriate IP
address for:
■
The PC where Filter Builder is running, and
■
The Switch 4007 on which you are trying to load the filter.
TFTP’s root directory must be configured with the path where filters
are stored, or the filter must be copied to TFTP’s configured root
directory.