McAfee IIP-S03K-NA-100I - IntruShield 3000 Sensor Appliance Product Manual page 36

McAfee® IntruShield® IPS 4.1
IntruShield Sensor 3000 Product Guide
Using fail-open hardware
The Gigabit Fail-Open kit (sold separately) minimizes the potential risks of in-line
IntruShield sensor failure on critical network links. Both Copper and Optical versions
of the Kit are available.
The Gigabit Ethernet (GE) Monitoring ports on IntruShield sensors are configured to
fail close by default; thus, if the sensor is deployed in-line, a hardware failure results
in network downtime. Fail-open operation for GE ports requires the use of the
optional external Bypass Switch provided in the Kit.
With the Bypass Switch in place, normal sensor operation supplies power to the
switch via a control cable. While the sensor is operating, the switch is "on" and
routes all traffic directly through the sensor. When the sensor fails, the switch
automatically shifts to a bypass state: in-line traffic continues to flow through the
network link, but is no longer routed through the sensor. Even after the sensor
comes back online, the ports configured as fail-open will remain in 'Bypass' mode
until the user manually puts them back to fail-open.
Caution 1:
either side of the sensor for a brief moment and requires the renegotiation of the
network link between the two peer devices connected to the sensor. Depending
on the network equipment, this disruption introduced by the renegotiation of the
link layer between the two peer devices may range from a couple of seconds to
more than a minute with certain vendors' devices.
Caution 2:
sensor and each of the peer devices are renegotiated to place the sensor back in
in-line mode. This outage, again, varies depending on the device, and can range
from a few seconds to more than a minute.
Installation and troubleshooting instructions for the Kit can be found in the Quick
Guide that accompanies the kit. For more information on the Optical kit, see
Optical Fail-Open Bypass Kit Guide.
Note that sensor outage breaks the link connecting the devices on
A very brief link disruption may also occur while the links between the
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Attaching cables to the I-3000 Sensor
Cabling for SPAN mode
Gigabit