We have a CISCO 800 series connected to 2 WAN channels, and 2 VLANs. The idea is to have VLAN1 always use WAN1 channel, and VLAN2 use WAN2 channel, but in case of connectivity failure switch to a working channel. Important to say that both WANs use DHCP-assigned IP addresses, so it's not possible to determine next-hop IP address etc.. Default gateways can change from time to time.
I got some problems with realizing this and will greatly appreciate your help:
First some config:
interface FastEthernet8 <---- WAN 2
ip address dhcp
ip nat outside
ip virtual-reassembly in
duplex auto
speed auto
!
interface GigabitEthernet0 <----- WAN 1
ip address dhcp
ip nat outside
ip virtual-reassembly in
duplex auto
speed auto
!
interface Vlan1 <---------- VLAN 1
description LAN interface
ip address 192.168.244.1 255.255.255.0
ip nat inside
ip virtual-reassembly in
ip policy route-map VLAN1LAN
!
interface Vlan2 <------- VLAN 2
ip address 192.168.243.1 255.255.255.0
ip nat inside
ip virtual-reassembly in
ip policy route-map VLAN2LAN
!
Here are the route-maps and access-lists:
ip access-list extended LAN1
permit ip 192.168.244.0 0.0.0.255 any
!
ip access-list extended LAN2
permit ip 192.168.243.0 0.0.0.255 any
!
route-map VLAN2LAN permit 10
match ip address LAN2
set interface FastEthernet8
!
route-map VLAN1LAN permit 10
match ip address LAN1
set interface GigabitEthernet0
!
Also have this for NAT:
route-map VLAN1NAT permit 10
match interface GigabitEthernet0
!
route-map VLAN2NAT permit 10
match interface FastEthernet8
!
ip nat inside source route-map VLAN1NAT interface GigabitEthernet0 overload
ip nat inside source route-map VLAN2NAT interface FastEthernet8 overload
This configuration works (VLAN1 <--nat---> WAN1 and VLAN2 <---nat---> WAN2) but does not solve the problem of channel breakdown switch.
So I implemented some sla and tracks:
track 10 ip sla 1 reachability
delay down 20 up 20
!
track 20 ip sla 2 reachability
delay down 20 up 20
!
ip sla 1
icmp-echo X.X.X.X source-interface GigabitEthernet0
threshold 500
timeout 500
frequency 5
ip sla schedule 1 life forever start-time now
ip sla 2
icmp-echo Y.Y.Y.Y source-interface FastEthernet8
threshold 500
timeout 500
frequency 5
ip sla schedule 2 life forever start-time now
This all works (tracks show channel availabiility), but now how do I apply these tracks to PBRs. Since I do not use
next-hop, and use set interface there is no option to set a track. I would like to do smth like this:
route-map VLAN2LAN permit 10 <---- high priority
match ip address LAN2
set interface FastEthernet8 track 2
!
route-map VLAN2LAN permit 30 <---- used when track 2 fails
match ip address LAN2
set interface GigabitEthernet0 track 1
!