IP SLA Fail back question

Unanswered Question
Jul 9th, 2009
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If my ISP were to go offline and the route that I am tracking is removed, is there a way to set a time before it can return to the main line? I know I could simply pull the cable if the line goes down but I am wondering if there is a way to automate it. For example ISP 1 goes down and ISP 2 takes over. Can I say that ISP 1 must be back up for 1 hour before switching back?

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johnspaulding Thu, 07/09/2009 - 08:33
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Yes,


After you create you IP SLA instance you create you track rtr's


under the following


track 1 rtr 1

delay down (seconds) up (seconds)


this should be the value you are looking for.


xcz504d1114 Thu, 07/09/2009 - 08:34
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What method are you using to track? And are you running any routing protocols? BGP can suppress a route for a specified time period if it goes down then back up.


With object tracking, I believe the maximum abmount of delay you can introduce is 180 seconds.


HTH,

Craig

ngthen@moonark.com Thu, 07/09/2009 - 09:01
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I am not using any routing protocols and I am using icmp-echo for tracking. I have 2 ISPs and one is pretty much just on standby unless the main goes down. For example


ip sla 1

icmp-echo 4.2.2.2

frequency 3

ip sla schedule 1 start-time now life forever

track 1 rtr 1 reachability


ip route 0.0.0.0 0.0.0.0 1.1.1.1 track 1

ip route 0.0.0.0 0.0.0.0 1.1.1.2 20


So I guess the question is with this config, is there a way to prevent the main from coming back online for a period of time?

xcz504d1114 Thu, 07/09/2009 - 09:08
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The other poster had the right answer for you:


track 1 rtr 1 reachability

delay down


But it only has a limit of 180 seconds.


HTH,

Craig

johnspaulding Thu, 07/09/2009 - 09:12
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Yes,


as previously posted


Taking your example


ip sla 1

icmp-echo 4.2.2.2

frequency 3

ip sla schedule 1 start-time now life forever


track 1 rtr 1 reachability

delay down (seconds) up (seconds)


As mentions only up to 180 seconds

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