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p3rad0x
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BGP Peering Advice

Thu Sep 06, 2018 12:17 pm

Good day a quick question.

We have 3 providers all different circuit speeds 1G / 2G /4G

Currently we have one BGP session to the 2G is and they only advertise a default route down to us.

Question is when the other 2 peers goes live wont one of them be overloaded ?

I will be taking in local routes from the 2 and 4 G provider and a default one for int traffic at the 1G one.

Any advice will be appreciated
 
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Anumrak
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Re: BGP Peering Advice

Thu Sep 06, 2018 1:18 pm

When you have multi-exits from your BGP segment, you don't need default routes already, you needs specific routes from all of them. Closest route from AS-Path attrubute will be chosen as next-hop to one of three ISP. If you want to force the traffic flow from 3rd to first ISP, play with ATT like as-path, local preference and MED.

None of ISP will be overloaded by you.
 
tiger4020
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Re: BGP Peering Advice

Thu Sep 06, 2018 11:19 pm

Hello.. I have a similar question and a problem I am facing for a while and have not received a proper solution.

We have 2 bgp peers.

Problem faced:
No pages load all of a sudden no pages load. If we shutdown one peer everything works great. The only solutions is to restart the router.

What it looks like from my perspective the outgoing traffic is unable to find a route between two peers until we restart and then everything works fine.

What may be the problem?

Thank you

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schadom
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Re: BGP Peering Advice

Fri Sep 07, 2018 1:40 am

Hello.. I have a similar question and a problem I am facing for a while and have not received a proper solution.

We have 2 bgp peers.

Problem faced:
No pages load all of a sudden no pages load. If we shutdown one peer everything works great. The only solutions is to restart the router.

What it looks like from my perspective the outgoing traffic is unable to find a route between two peers until we restart and then everything works fine.

What may be the problem?

Thank you

Sent from my SAMSUNG-SM-G935A using Tapatalk

What setting are you using in /ip settings rp-filter for source validation?
https://wiki.mikrotik.com/wiki/Manual:I ... Properties

You might wanna try "loose" or "no" instead of strict source validation, if set.
 
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StubArea51
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Re: BGP Peering Advice

Fri Sep 07, 2018 8:26 pm

This largely depends on your BGP edge design and whether or not the peers are fully meshed inside your AS. If the routes learned from your upstreams are only present at the border routers then you'll need aggregate routes injected form the border routers to draw traffic towards one of those peers.

An example. Apple Computers uses 17.0.0.0/8 , if you want traffic destined for Apple to traverse a specific upstream, then you can advertise a 17.0.0.0/8 summary into your network with a local preference assigned to the BGP border router you want it to go to.

Obviously you can't do this for every BGP prefix, but identifying large IP blocks for webscale companies like Apple, Facebook, Google, YouTube, etc and advertising aggregates or leaking specific routes into the interior of your network can help to balance traffic across the different speed upstreams.

BGP Communities if they are available from your upstream can be used to help manage traffic inbound to your AS and achieve some load balancing. Check woth your provider to see what options you have to set local preference within your provider's AS and prioritize or de-prioritize your prefix advertisements within the upstream provider's AS.

Another option is to use software like Noction to help manage advertisements dynamically and detect packet loss and congestion. There is a free version that works with MikroTik.

https://www.noction.com/irp-lite

Finally, as this is a very complex topic, if you want professional help with designing this, we'd be happy to help and work on this kind of solution every day. Visit https://iparchitechs.com/services/consu ... onsulting/ to connect with us.

Good luck!
 
tiger4020
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Re: BGP Peering Advice

Sun Sep 09, 2018 8:30 am

Thank guys.. Currently I have set the ipsettings to loose earlier it was set to "no" with test this feature if it works.

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tiger4020
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Re: BGP Peering Advice

Sun Sep 09, 2018 8:31 am

@IParchitech will definitely lookup your link and buzz you for professional help.

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