IP SLA issue

dennisbelliveau · ‎10-01-2013

Good Day,

I am trying to resolve an issue using IP SLA and tracking. I have a router that has multiple routes. I have 2 that are over wireless connections and one that is a last resort for Cellular. I have a issue where both wireless routes are up and i want the route with the better throughput/bandwidth at that time to be the primary route. here is a portion on the configuration that i am working with. any advice would be appreciated..

ip route 0.0.0.0 0.0.0.0 10.10.10.1 track 1 10

ip route 0.0.0.0 0.0.0.0 10.10.10.2 track 2 20

ip route 0.0.0.0 0.0.0.0 10.10.10.3 50

ip sla 1

icmp-echo 10.10.10.1 source-ip 10.10.10.20

timeout 500

threshold 2

frequency 15

ip sla schedule 1 life forever start-time now

ip sla 2

icmp-echo 10.10.10.2 source-ip 10.10.10.20

timeout 500

threshold 2

frequency 15

ip sla schedule 2 life forever start-time now

track 1 ip sla 1 reachability

delay down 30 up 45

track 2 ip sla 2 reachability

delay down 30 up 45

Vishesh Verma · ‎10-01-2013

IP SLA cannot help you with routing traffic based on link performance (Bandwidth/delay/throughput). It can only help you with reachability.

You need PfR to intelligently route based on performance -

http://www.cisco.com/en/US/products/ps8787/products_ios_protocol_option_home.html

Sandeep Choudhary · ‎10-01-2013

HI Dennis,

As Vishesh told u that:

IP SLA cannot help you with routing traffic based on link performance (Bandwidth/delay/throughput). It can only help you with reachability.

This is absolutely correct form my point of view.

IP SLA is only used to to tack the link. If one link is dwon then another can come up.

Here is the example.

R1(config)# ip sla 1

R1(config)#icmp-echo 2.2.2.2 source-interface FastEthernet0/0

R1(config)# timeout 1000

R1(config)#threshold 2

R1(config)# frequency 3

R1(config)# ip sla schedule 1 life forever start-time now

R1(config)# track 1 ip sla 1 reachability

R1(config)#ip route 0.0.0.0 0.0.0.0 2.2.2.2 track 1

R1(config)# ip route 0.0.0.0 0.0.0.0 3.3.3.3 10

You can aslo see the status of tracking by:

R1# show track

Track 1

IP SLA 1 reachability

Reachability is Down

1 change, last change 00:03:19

Latest operation return code: Unknown

Regards

Hope it Helps

mit127 · ‎10-03-2013

Thank you for the responses. I will look at Performance routing.