Technical Tip: Load balancing per-rule

[Shilpa1]

Description
This articles describes SD-WAN load balancing for all explicit rules.

When a rule is hit, traffic is hashed based on the defined load balancing algorithm among the selected SD-WAN members that satisfy the defined SLA.
Previously, SD-WAN load balancing was only available on the last implicit rule.
This covered all the SD-WAN interface members, but when an explicit SD-WAN rule was created, it prevented load balancing from occurring for that protocol, and traffic was only routed over a single interface.

Solution

To add load balancing to a rule from GUI.

1) Go to Network -> SD-WAN Rules.
2) Edit a rule, or create a new one.
3) Under Outgoing Interfaces, select a Strategy, Interface preference, and Required SLA target or Measured SLA.

4) Select 'OK' to apply the  changes.

To add load balancing to a rule from CLI.

# config system virtual-wan-link
    config service
        edit 1
            set name "balance"
            set mode load-balance
            set dst "10.100.20.0"
            config sla
                edit "ping"
                    set id 2
                next
            end
            set priority-members 1 2 3
        next
    end
end

To diagnose the load balancing status.

FGT_A (root) # diagnose sys virtual-wan-link  health-check
Health Check(ping):
Seq(2): state(alive), packet-loss(40.000%) latency(0.049), jitter(0.017) sla_map=0x3
Seq(1): state(alive), packet-loss(0.000%) latency(0.020), jitter(0.005) sla_map=0x3

FGT_A (root) # diagnose sys virtual-wan-link  service

Service(22): Address Mode(IPV4) flags=0x0
  TOS(0x0/0x0), Protocol(0: 1->65535), Mode(load-balance)
  Members:
    1: Seq_num(1), alive, sla(0x1), num of pass(1), selected
    2: Seq_num(2), alive, sla(0x1), num of pass(1), selected
  Dst fqdn: gmail.com(119)