I have a client who is has a requirement to run nat on their router and needs a backup interface to dial out if the the primary goes down.
I have tryed this out in the lab and have got this configuration working.
(NB, using all ethernet on this test router)
!
interface FastEthernet0/0
backup interface FastEthernet0/1
ip address 10.0.1.254 255.255.255.0
ip access-group 111 in
ip nat outside
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 10.0.1.254 255.255.255.0
ip access-group 111 in
duplex auto
speed auto
!
interface FastEthernet1/0
ip address 10.0.2.254 255.255.255.0
ip nat inside
duplex auto
speed auto
!
ip nat translation timeout 5
ip nat translation tcp-timeout 5
ip nat translation pptp-timeout 5
ip nat translation udp-timeout 5
ip nat translation finrst-timeout 5
ip nat translation syn-timeout 5
ip nat translation dns-timeout 5
ip nat translation icmp-timeout 5
ip nat translation max-entries 5
ip nat pool NATPOOL 10.0.1.250 10.0.1.250 netmask 255.255.255.0
ip nat inside source list 100 pool NATPOOL
ip nat inside source static 10.0.2.1 10.0.254.1
!
access-list 100 permit ip 10.0.2.0 0.0.0.255 any
access-list 111 permit icmp any any
access-list 111 permit tcp any host 10.0.254.1 eq telnet
!
All works fin, except on failover the nat breaks and takes about 90-120secs to timeout and then starts working again. If any data is sent within that time the timeout starts again. This is with all timers set to 5 seconds. Dos anyone have any pointers on how to avoid this?
