Description
The article describes how to set the minimum number of links for a rule to take effect.
Scope
FortiGate.
Solution
In SLA and load-balance modes, it is possible to specify the number of links that can be up for the rule to take effect.
Example.
In this example, ports 1 to 4 each have 10Mbps of bandwidth, and port 5 has 50Mbps.
An application requires 35Mbps of bandwidth, so the SD-WAN rule balances the traffic between ports 1 to 4.
If one of the links goes down, all of the traffic must be passed to port 5. As a result, the minimum required number of links is 4.
If the number of members that meet the SLA is below the minimum threshold, the rule is disabled and skipped during the rule-matching state.
The setting that controls this behavior is 'minimum-sla-meet-members', which is set to 0 by default. This means that the minimum number of members is not considered.
To set the minimum number of links in a rule:
From the CLI.
config system sdwan
config service
edit 1
set mode load-balance
set minimum-sla-meet-members 4
set dst <destination>
config sla
edit <sla>
set id <id>
next
end
set priority-members 1 2 3 4
next
end
end
Note: When using multiple SLA on the configured SD-WAN service ID, only the members which pass the 'same and greatest' number of SLA will be used to load-balance traffic.
