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Just curious if we can use both bgp with dual ISP for redundancy.  We're advertising a /24 to both ISPs and that is for inbound traffic.  They are using static route for outbound traffic. We're adding a second static route with admin distance and we will track this.  This should be ok and not have any issue?

This URL has a similar setup:  http://showipbgp.com/bgp-configurations/40-cisco/73-3-3-1-cisco-dual-bgp-with-as-prepend-redundancy.html for inbound traffic.  Ignore the outbound traffic as we're using IP SLA with tracking.

Also, noticed that we're not introducing a new ISP so there is a filter list to block any routes learned from the other ISP and vice versa.
Cisco* bgp

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Jan Bacher

8/22/2022 - Mon
Jan Bacher

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Thank you for the response. Below is the output of the show ip bgp (with IP/AS # changed).  They do not receive any default route so that is why they are using default route.  Purpose of the IP SLA is to track the ISP1 for failure and then fail over accordingly.

router>show ip bgp
BGP table version is xxxxx, local router ID is x.x.x.x
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path
*> 0 88888 7849 2829 4826 38803 56203 i
*> 0 88888 7849 2829 4826 38803 56203 i
*> 0 88888 7849 2829 4826 38803 56203 56203 56203 i
*> 0 88888 7849 2516 7670 18144 i
*> 0 88888 7849 3492 38040 23969 ?
*> 0 88888 7849 3492 38040 9737 i
*> 0 88888 7849 3492 38040 9737 i
Jan Bacher

You don't need a default route when you are receiving full routes.  Think of it this way:  if you providers send you full routes they do not know how to route an unknown prefix any more than you do.

And with SLA, if one BGP session dies, the other will handle your traffic.   You don't need or want SLA.

I would recommend against SLA with BGP.  Ugh.
Predrag Jovic

Do not assign points to this one! :)

As Jane already said, if you are receive full routing table you don't need default route.
Default route is needed only in the case if router is not receiving full routing tables from connected ISP routers.
Your help has saved me hundreds of hours of internet surfing.
Jan Bacher

And you still don't need SLA!

As mentioned, they do not receive any default routes. They are using static routes. The BGP is for inbound traffic to their /24.  The static routes (with two static routes, one with higher admin) and with IP SLA, we're tracking ISP1 and if it fails, ISP2 takes over and default routes are for outbound traffic.

Ok, think we're good.

We will not need IP SLA as the second ISP will be used because of the second default route with a higher admin status when the interface fails as both interfaces are directly connected.

IP SLA is for tracking of ping.

Thank you!
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Jan Bacher

LateNaite would you please close this question?
Jan Bacher

This question was answered.