VyOS : 

set interfaces tunnel tun0 address '172.16.100.1/24'
set interfaces tunnel tun0 description 'Zscaler_Pri-Washington'
set interfaces tunnel tun0 encapsulation 'gre'
set interfaces tunnel tun0 mtu '1400'
set interfaces tunnel tun0 remote '192.2.0.1'
set interfaces tunnel tun0 source-interface 'eth0'
set interfaces tunnel tun1 address '172.16.102.1/24'
set interfaces tunnel tun1 description 'Zscaler_Sec-New York'
set interfaces tunnel tun1 encapsulation 'gre'
set interfaces tunnel tun1 mtu '1400'
set interfaces tunnel tun1 remote '192.2.0.2'
set interfaces tunnel tun1 source-interface 'eth0'
set load-balancing wan disable-source-nat
set load-balancing wan flush-connections
set load-balancing wan interface-health tun0 failure-count '3'
set load-balancing wan interface-health tun0 nexthop '172.16.100.2'
set load-balancing wan interface-health tun0 success-count '1'
set load-balancing wan interface-health tun0 test 10 resp-time '5'
set load-balancing wan interface-health tun0 test 10 target '10.10.10.10'
set load-balancing wan interface-health tun0 test 10 ttl-limit '1'
set load-balancing wan interface-health tun0 test 10 type 'ping'
set load-balancing wan interface-health tun1 failure-count '3'
set load-balancing wan interface-health tun1 nexthop '192.2.0.2'
set load-balancing wan interface-health tun1 success-count '1'
set load-balancing wan interface-health tun1 test 10 resp-time '5'
set load-balancing wan interface-health tun1 test 10 target '20.20.20.20'
set load-balancing wan interface-health tun1 test 10 ttl-limit '1'
set load-balancing wan interface-health tun1 test 10 type 'ping'
set load-balancing wan rule 10 destination port '80,443'
set load-balancing wan rule 10 failover
set load-balancing wan rule 10 inbound-interface 'eth0'
set load-balancing wan rule 10 interface tun0 weight '2'
set load-balancing wan rule 10 interface tun1 weight '1'
set load-balancing wan rule 10 protocol 'tcp'

table ip mangle {
	chain PREROUTING {
		type filter hook prerouting priority mangle; policy accept;
		counter packets 5 bytes 456 jump WANLOADBALANCE_PRE
	}

	chain WANLOADBALANCE_PRE {
	}

	chain ISP_tun0 {
		counter packets 0 bytes 0 ct mark set 0xc9
		counter packets 0 bytes 0 meta mark set 0xc9
		counter packets 0 bytes 0 accept
	}

	chain ISP_tun1 {
		counter packets 0 bytes 0 ct mark set 0xca
		counter packets 0 bytes 0 meta mark set 0xca
		counter packets 0 bytes 0 acceptshow c

set load-balancing wan rule 10 destination port '80'
set load-balancing wan rule 10 failover
set load-balancing wan rule 10 inbound-interface 'eth0'
set load-balancing wan rule 10 interface tun0 weight '2'
set load-balancing wan rule 10 interface tun1 weight '1'
set load-balancing wan rule 10 protocol 'tcp'
set load-balancing wan rule 11 destination port '443'
set load-balancing wan rule 11 failover
set load-balancing wan rule 11 inbound-interface 'eth0'
set load-balancing wan rule 11 interface tun0 weight '2'
set load-balancing wan rule 11 interface tun1 weight '1'
set load-balancing wan rule 11 protocol 'tcp'

# Warning: table ip mangle is managed by iptables-nft, do not touch!
table ip mangle {
	chain WANLOADBALANCE_PRE {
		iifname "eth0" tcp dport 80 ct state new counter packets 0 bytes 0 jump ISP_tun0
		iifname "eth0" tcp dport 80 counter packets 0 bytes 0 meta mark set ct mark
		iifname "eth0" tcp dport 443 ct state new counter packets 0 bytes 0 jump ISP_tun0
		iifname "eth0" tcp dport 443 counter packets 0 bytes 0 meta mark set ct mark
	}


table ip mangle {
	chain PREROUTING {
		type filter hook prerouting priority mangle; policy accept;
		counter packets 5 bytes 456 jump WANLOADBALANCE_PRE
	}

	chain WANLOADBALANCE_PRE {
	}

	chain ISP_tun0 {
		counter packets 0 bytes 0 ct mark set 0xc9
		counter packets 0 bytes 0 meta mark set 0xc9
		counter packets 0 bytes 0 accept
	}

	chain ISP_tun1 {
		counter packets 0 bytes 0 ct mark set 0xca
		counter packets 0 bytes 0 meta mark set 0xca
		counter packets 0 bytes 0 acceptshow c