HP 800 Series, User Manual

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Remote Device Activity Capture
Creating a DAC Host
12-2
Creating a DAC Host
NAC 800 auto-discovers endpoints on your network so that the testing and
transition from quarantine to non-quarantine areas happens quickly and
smoothly after an endpoint is booted up. NAC 800 also relies on auto-discovery
functionality to track DHCP IP address transitions so that it can continue to
communicate seamlessly with endpoints after an IP change. The utility used
for auto-discovery is Device Activity Capture (DAC). DAC listens or sniffs the
network for, most importantly, DHCP traffic, but can be configured to discover
other types of IP traffic if needed (such as from static IP addresses). DAC
listens for DHCP ACK (a unicast from the DHCP server to the endpoint)
messages so that it knows exactly when an endpoint has received a new IP
address and can be tested with a TCP/IP connection. DAC works in a number
of configurations:
■ DHCP (Router) and Inline Mode – DAC runs on the Enforcement
Servers (ES) and discovers endpoints when they generate traffic
across the ES bridge. There is no need for you to do any extra
configuration of DAC in these modes.
■
802.1X Mode
• Mirror Port – DAC runs on the ESs. The eth1 interface of the ES is
connected to a mirror port on a switch that mirrors DHCP traffic. The
eth1 interface can also be configured to listen on a mirror port for
other types of traffic to discover endpoints with static IP addresses.
Select the
local
radio button in the
Home window>>System configura-
tion>>802.1X Quarantine method>>Quarantining
window to enable this
mode.
• Remote
DAC (RDAC)
– DAC runs as a standalone service on a Windows
DHCP server and relays DHCP information back to the ESs. DAC can
also be configured to run on a non-DHCP server to discover endpoints
with static IP addresses. Select the
remote
radio button in the Select
the local radio button in the Home window>>System configura-
tion>>802.1X Quarantine method>>Quarantining window to enable this
mode.
This section explains how to install DAC on a remote system. For Windows
servers, use the Windows installer to set up the first interface, then manually
add other interfaces.
TIP:
When DAC is installed on the ES, it is sometimes referred to as Embedded
DAC (EDAC). When DAC is installed remotely, it is sometimes referred to as
Remote DAC (RDAC).