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dsvxaey

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How do I setup ISP failover and load balancing on a Cisco 1841 router?

I've been following the instructions on this site, http://www.inacom-sby.net/Shawn/post/2007/11/Getting-Dual-ISPs-running-on-Cisco-1811-and-above-routers(Part-1).aspx, for setting this router for ISP load balancing and failover.  I run into a problem at one of the steps.  track 1 rtr 1 reachability  It's not working.  I get this error.  % Invalid input detected at '^' marker  Can someone fill me in on why?  

Also, I want to make sure this configuration will work?  I know that the T-1 interface is not setup correctly.  I'm waiting on the information from my ISP for me to complete it.
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname PROXY
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
!
resource policy
!
ip cef
!
!
no ip dhcp use vrf connected
ip dhcp excluded-address 192.168.2.1 192.168.2.99
!
ip dhcp pool STSCS
   network 192.168.2.0 255.255.255.0
   default-router 192.168.2.5
   dns-server 4.2.2.2
   domain-name sts-cs.com
   lease 3
!
!
no ip domain lookup
ip sla 1
 icmp-echo 4.2.2.2
 timeout 500
ip sla schedule 1 life forever start-time now
!
!
track 1 stub-object
!
class-map match-all VOIP
 match protocol rtp audio
class-map match-all VOIP_Control
 match protocol sip
!
!
policy-map VOIP_PM
 class VOIP
  priority percent 50
 class VOIP_Control
  priority percent 20
!
!
!
!
interface Loopback0
 ip address 10.108.1.1 255.255.255.0
 ip nat outside
!
interface FastEthernet0/0
 description ATTDSL
 bandwidth 512
 bandwidth receive 6144
 ip address 65.5.44.25 255.255.255.0
 ip nbar protocol-discovery
 ip nat outside
 duplex auto
 speed auto
 service-policy output VOIP_PM
!
interface FastEthernet0/1
 description Internal
 ip address 192.168.2.5 255.255.255.0
 ip nbar protocol-discovery
 ip nat inside
 duplex auto
 speed auto
!
interface Serial0/0/0
 description ATTT-1
 bandwidth 1544
 no ip address
 ip nbar protocol-discovery
 ip nat outside
 service-policy output VOIP_PM
!
!
no ip http server
ip nat inside source route-map ATTDSL interface FastEthernet0/0 overload
ip nat inside source route-map ATTT-1 interface Serial0/0/0 overload
!
access-list 100 permit ip any any log
route-map ATTT-1 permit 10
 match ip address 1
 match interface Serial0/0/0
!
route-map ATTDSL permit 10
 match interface FastEthernet0/0
!
!
control-plane
!
!
line con 0
line aux 0
line vty 0 4
 login
!
scheduler allocate 20000 1000
end

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Avatar of Pugglewuggle
Pugglewuggle
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So just to confirm - you have a single 1841 that you will be doing loadbalancing/backup interfaces on? You are NOT using multiple routers with HSRP, is this correct?
The way it basically works is that you setup "interface tracking" to track the interfaces and remove the routes from the round robin interface load balancing. One important thing to note is that the load balancing never actually stops - it's just that the route of the interface that's down is taken out of the LB pool while it's down - effectively, everything is then load balanced to the interface (or interfaces) that are still up.
Cheers! Let me know if you have any questions!
hi

 Pugglewuggle: Is it possiplle to do wan failover between to ISP withot BGP on cisco router.
                   
regards,devang
Yes, it is possible to do a WAN failover without BGP - basically just track interfaces and costs if using dynamic routing.
You can in fact do it with pretty much any type of connection - even a dial up line with the right WIC on the router!
Cheers!
hi
Pugglewuggle: can u just explain how nattin will work if i have two internet connect fron different provider on same router.

regards,
devang
Well you assign each interface as ip nat outside so they can be used in round robin LB for NAT. Then if one goes down the other one takes over. And when it comes back up, everything goes back to normal.
Avatar of dsvxaey
dsvxaey

ASKER

Ok, I understand how it works.  I'm just wondering how to add the tracking ability for failover.  I can't seem to figure that part out.  Thanks.
To "track" interfaces when not using HSRP and two routers, you need to use "floating static routes". Here is a funny article that helps you understand them nice and easily:
http://www.routergod.com/charlesmanson/
Don't know why they picked charles manson for that one though... usually they pick someone better.
Cheers!
Avatar of dsvxaey

ASKER

I can't get this working.  Standard pinging won't go out over the T1.  Can somebody point me in the right direction?  The router hands out DHCP leases just fine, but I can't ping externally over the T1 from a client or from the router itself.   Thanks.
Do you have a route setup for the T1? That is often an issue.
Avatar of dsvxaey

ASKER

Hmm, not sure.  Give me an example of what the route would look like.
ASKER CERTIFIED SOLUTION
Avatar of Pugglewuggle
Pugglewuggle
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