How do I configure route precedence on a firewall?

09/29/2023 235 People found this article helpful 487,373 Views

Description

Before SonicOS 6.5 SonicWall firewalls prioritized traffic based on Source IP, Destination IP and Service fields.

Now, the Type Of Service (TOS, it's a 8-bit field contained in the IP Header of the packet) is included in the routing logic when taking routing decisions. This will allow you to configure multiple static routes with the same Source IP, Destination IP and Service but with a different TOS value.

Routes can now be prioritized based on metric. Previously they were prioritized based on specificity of a route (longer prefixes prioritized over short prefixes). The new Metric-Weighted option will allow metric to take precedence on prioritization over route specificity.

Cause

Resolution for SonicOS 7.X

This release includes significant user interface changes and many new features that are different from the SonicOS 6.5 and earlier firmware. The below resolution is for customers using SonicOS 7.X firmware.

There are two types of route prioritization added from 6.5 and later:

Route Prioritization based on TOS:
1. Navigate to Policy | Rules and Policies | Routing Rules
2. Modify or Add a static route
3. Click on the Advanced tab
4. Type the TOS Value and TOS Mask to prioritize the route.

NOTE: You can configure multiple routes with same Source IP, Destination IP and Service: they will be prioritized based on the TOS value.

Route Prioritization with Weighted-Metrics - It will allow the metric to take precedence in prioritization over the route specificity.
The routing logic will take the following in consideration: Route Class; Metric; Cumulative Specificity of Source, Destination, Service and TOS fields.
1. Navigate to Network | System | Dynamic Routing
2. Go to the Settings tab
3. Enable Prioritize routes by metric within route classes
4. Navigate to Policy | Rules and policies | Routing Rules, Modify or Add a static route
5. Specify the Metric based on the priority of the rule

Resolution for SonicOS 6.5

This release includes significant user interface changes and many new features that are different from the SonicOS 6.2 and earlier firmware. The below resolution is for customers using SonicOS 6.5 firmware.

There are two types of route prioritization added from 6.5 and later:

Route Prioritization based on TOS:
1. Go to the Manage tab
2. Click Network | Routing
3. Modify or Add a static route
4. Click on the Advanced tab
5. Type the TOS Value and TOS Mask to prioritize the route.

NOTE: You can configure multiple routes with same Source IP, Destination IP and Service: they will be prioritized based on the TOS value.

Route Prioritization with Weighted-Metrics - It will allow the metric to take precedence in prioritization over the route specificity.
The routing logic will take the following in consideration: Route Class; Metric; Cumulative Specificity of Source, Destination, Service and TOS fields.
1. Go to the Manage tab
2. Click Network | Routing
3. Go to the Settings tab
4. Enable Prioritize routes by metric within route classes
5. Modify or Add a static route
6. Specify the Metric based on the priority of the rule