Hi,
I was actually just testing this out of interest today. I hadnt done Dual ISP before with the ASA alone as we have handled that in other upstream routers usually.
However this is what I configure and it worked fine. This is from an ASA5520 so only interface IDs/names should be different
interface GigabitEthernet0/0
description Primary ISP
nameif WAN-1
security-level 0
ip address 255.255.255.0
!
interface GigabitEthernet0/1
description Secondary ISP
nameif WAN-2
security-level 0
ip address 255.255.255.0
route WAN-1 0.0.0.0 0.0.0.0 192.168.101.1 1 track 200
route WAN-2 0.0.0.0 0.0.0.0 192.168.102.1 254
sla monitor 200
type echo protocol ipIcmpEcho interface WAN-1
num-packets 2
timeout 2000
frequency 3
sla monitor schedule 200 life forever start-time now
track 200 rtr 200 reachability
object-group network LAN-NETWORKS
network-object
network-object
nat (LAN,WAN-1) after-auto source dynamic LAN-NETWORKS interface
nat (LAN,WAN-2) after-auto source dynamic LAN-NETWORKS interface
Hope this helps
- Jouni