Page 138 SonicWALL Internet Security Appliance Administrator’s Guide
Understanding the Access Rule Hierarchy
The rule hierarchy has two basic concepts:
1. Specific rules override general rul es:
An individual service is more specific than the Default service.
A single Etherne t link, such as LAN or W AN, is more specific tha n * (all).
A single IP addre ss is more specific tha n an IP address range.
2. Equally specific Deny rules overr ide Allow rules.
Rules are disp layed in the Current Network Access Rules list from the mo st specific to th e least
specific, and rules at the top override rules listed below. For example, consider the section of the
Rules window shown below.
The Default Allow Rule (#7) at the bottom of the page allows all traffic from the LAN to the WAN.
However, Rule #1 blocks IRC (Chat) traffic from a computer on the LAN to a server on the WAN.
The Default Deny Rule (#6) blocks all traffic from the WAN to the LAN, however, Rule #2 overrides
this rule by allowing Web traffic from the WAN to the LAN.