Installation guide

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Type
Family or Plugin. If “Family” is chosen, then when plugin updates occur, new plugins
will automatically be enabled for plugin families that are enabled. If “Plugin” is enabled,
only the currently enabled plugins are enabled. New plugins must be manually enabled
by the user. This is beneficial where strict control over new plugins is required.
Changing from “Family” to “Plugin”, or vice-versa, clears all currently
enabled plugins. Please make a note of all enabled plugins before
changing this option so that they can be enabled afterwards.
The “Scan” frame controls basic scan options for the scan:
Table 19 – Scan Options
Option
Description
Safe Checks
Nessus can attempt to identify remote vulnerabilities by interpreting banner information
and attempting to exercise a vulnerability. When “Safe Checks” is enabled, the second
step is skipped. This is not as reliable as a full probe, but is less likely to negatively
impact a targeted system.
Silent Dependencies
If this option is checked, the list of dependencies is not included in the report. If you
want to include the list of dependencies in the report, uncheck the box.
Consider Unscanned Ports
as Closed
With this setting enabled, ports that are not enumerated by the port scan will not be
tested. For example, scanning ports 21, 22, and 23 will only test those ports and not
any other port.
The “Port Scanners” frame controls which methods of port scanning should be enabled for the scan:
Table 20 – Port Scanner Options
Option
Description
TCP Scan
Use Nessus’ built-in TCP scanner to identify open TCP ports on the targets. This
scanner is optimized and has some self-tuning features.
On some platforms (e.g., Windows and Mac OS X), if the operating
system is causing serious performance issues using the TCP scanner,
Nessus will launch the SYN scanner instead.
UDP Scan
This option engages Nessus’ built-in UDP scanner to identify open UDP ports on the
targets.
UDP is a “stateless” protocol, meaning that communication is not done
with handshake dialogues. UDP based communication is not reliable,
and because of the nature of UDP services and screening devices, they
are not always remotely detectable. Utilizing the UDP scanner will
noticeably increase scanning time.
SYN Scan
Use Nessus’ built-in SYN scanner to identify open TCP ports on the targets. SYN
scans are a popular method for conducting port scans and generally considered to be
a bit less intrusive than TCP scans. The scanner sends a SYN packet to the port, waits