I have 192.168.1.1/24 on my eth0 as LAN, VPN set up.
For some cases, I want to visit some web site via VPN, I set up a socks 5 proxy.
But socks 5 is not an option for iPhone & Android by default.
So I added 192.168.10.1/24 to eth0 at the same time, traffic from 192.168.10.0/24 are all forwarded to VPN interface.
set interfaces ethernet eth0 address 192.168.10.1/24
set firewall group network-group VPN_SRC_ZONE description 'network for full vpn route'
set firewall group network-group VPN_SRC_ZONE network 192.168.10.0/24
set firewall modify AUTO_VPN rule 700 action modify
set firewall modify AUTO_VPN rule 700 description 'src based routing'
set firewall modify AUTO_VPN rule 700 modify table 2
set firewall modify AUTO_VPN rule 700 source group network-group VPN_SRC_ZONE
If I want my iPhone traffic fully routed to VPN, I just need to change my iPhone WiFi addresses.