BGP Peers

RouterOS General
1

I have 2 ISPs connected to a Mikrotik Router which I am using for BGP. In Winbox, how can I force all traffic to go to a specific ISP ? If I simply pull the plug on the one I don’t want, everything stops working. So I assume I have something setup wrong…Any help would be appreciated. Please remember, I use Winbox, I am not familiar with the Router OS Command Line.

Thanks,

Parry Sands

2

You can add an additional 0.0.0.0/0 route with a distance of 2 to the second isps network, or setup ecmp gateways. Use check-gateway=arp if you want to automatically remove that route when its unreachable.

3

Example:

ISP1 = 1.1.1.1

IPS2 = 2.2.2.2

ME = 3.3.3.3

I assume then that I should have this:
route 0.0.0.0 1.1.1.1 distance 1
route 0.0.0.0 2.2.2.2 distance 2

This is assuming that I wan’t my traffic to go out through ISP #1

Thanks,

4

yep - perfect

Sam

5

Thank You very much…I’ll give it a shot later and see what happens.

6

How do you set this up to have incoming transfer come through one of the isps? I have a similar BGP setup

Please advise .

7

To force more traffic in one ISP than the other you can use AS prepending… its not perfect but helps influence the traffic to one side or the other.

8

How to do this with MT im running 2.9.30 and routing-test. I want to make sure more incoming comes in via 1 of the isps

9

Here is one filter that I use to make the path look longer for one incoming route:

add chain=level3-out prefix=204.16.xxx.0/24 prefix-length=24 invert-match=no
action=accept set-bgp-prepend=2 comment=“” disabled=no

This adds 2 extra AS-PATHs to the length which makes it less preferred to the outside world.

Sam

10

Which version of mikrotik are you using ?

11

That above filter was from 2.9.26… and it’s been up for a whopping 96d now : )

Sam

12

and your advetising this tou level3 only OR to the other provider as well ?
This makes level3 appear further away so your other provider will become the preferred for incoming correct?

add chain=level3-out prefix=204.16.xxx.0/24 prefix-length=24 invert-match=no \ action=accept set-bgp-prepend=2 comment="" disabled=no
13

Yes, for one of our /24s we annouce out both peers we want most of the traffic to come in Cogent… so the level3 path is prepended to make it look less preferrable.

14

Yes, for one of our /24s we annouce out both peers we want most of the traffic to come in Cogent… so the level3 path is prepended to make it look less preferrable.

15

Yes, for one of our /24s we annouce out both peers we want most of the traffic to come in Cogent… so the level3 path is prepended to make it look less preferrable.

16

I did this it has no effect . Want to do exactly the same that you have done to have certain / all classes incoming via a partciular . What I have done is advertised out those classes out to the one I dont want to have incoming from – yipes . But has no effect on the incoming so far. Looked through the looking glass i dont see anything. How do i check or do i prepend further away (more than 2) ?

17

Sam, have you tried any other version that have been stable for extended time periods? I’m going to be implementing a MikroTik along side of my existing Cisco for BGP (each running eBGP to upstream providers, and iBGP between each other for true failover and redundancy)

I don’t have a copy of the x86 2.9.26 package, and I really don’t want to load a version that hasn’t yet proved it’s stability with BGP.

18

USed 2.9.30 up 40+ days.

19

sure beats the 16 day average I’m getting with my Cisco 7204/NPE300/256mb betweeen reboots… and I’ve got a copy of x86-2.9.30 :smiley:

anyone else had any BGP implementations running for more then 30 days?

20

I didnt know the npe300 gave only 16 days its supposed to be very stable if you have the l8st ios