Community discussions

MikroTik App
 
scotthellewell
just joined
Topic Author
Posts: 13
Joined: Wed Jun 27, 2012 11:24 pm

Routing Issue (BGP and non BGP)

Wed Jun 27, 2012 11:58 pm

I have 3 sites

Site A - BGP Peer to Internet and Metro Ethernet to Site B

Site B - BGP Peer to Internet and Metro Ethernet to Site A and Site C

Site C - BGP Peer to Internet and Metro Ethernet to Site B

I have 2 - IPV4 /24s that are routed over BGP through the peer at each site.
I have IBGP running between the sites. Each site has a RouterOS box.

Site A also has a /28 that is routed
Site B also has a /29 that is routed
Site C also has a /29 that is routed

The IP addresses from the /24's work great. The problem is that the smaller subnets are getting redirected to the shorted AS Path and when Site B /29 goes out Site A the routing fails. How do I force traffic from Site A's /28 to only go out through Site A and the same for Site B and Site C?

I realize that anything utilizing the /28 and /29s will not have the redundancy offered by BGP.

The other option I would like to look into is failing over to a VPN between sites if the Metro Ethernet ever goes down.

Also, is there any way to auto apply firewall rules applying to the /24's to all of the routers automatically?

Thanks

Scott Hellewell
 
cupis
Frequent Visitor
Frequent Visitor
Posts: 74
Joined: Sun Apr 10, 2011 1:25 am

Re: Routing Issue (BGP and non BGP)

Sat Jun 30, 2012 3:39 pm

It sounds like you need to look into "source" or "policy" routing, so that any traffic from the /29 is routed to a specific peer, rather than using your main routing table (which may cause the traffic to be sent out via the "incorrect" peer).

Some online examples/documentation:

http://wiki.mikrotik.com/wiki/Manual:PCC
http://farolan.blogspot.com/2009/03/how ... teros.html

Regards,
 
scotthellewell
just joined
Topic Author
Posts: 13
Joined: Wed Jun 27, 2012 11:24 pm

Re: Routing Issue (BGP and non BGP)

Sun Jul 01, 2012 1:47 am

Thank you for the response. I will take a look at what you have provided and see if I have any more questions.
 
Martinrf77
just joined
Posts: 1
Joined: Fri Aug 17, 2012 5:40 pm

Re: Routing Issue (BGP and non BGP)

Fri Aug 17, 2012 5:45 pm

Hi all, I have a problem with creating an instance of BGP. I'm ConnectRetry Timer Expired.
The issue is that my AS in the BGP configuration is 6 digits and when you finish configuring the AS tells me what exchanges as AS = 4.43, instead of telling me AS = 26XXXX.
I need your help please. The version 2.13 is the winbox RouterOS 5.13
 
cupis
Frequent Visitor
Frequent Visitor
Posts: 74
Joined: Sun Apr 10, 2011 1:25 am

Re: Routing Issue (BGP and non BGP)

Mon Aug 20, 2012 10:14 am

Hi,

You should probably start a new topic for this issue, perhaps with the subject "32-bit ASN issue".

Regards,
 
MikroTikIQ
Trainer
Trainer
Posts: 44
Joined: Sat Jun 16, 2012 1:42 pm

Re: Routing Issue (BGP and non BGP)

Thu Sep 06, 2012 12:45 pm

Hi Scott Hellewell

I would like to ask how many connection have to Internet ..?

How man eBGP peer you with other ISP?

To improve the Internal routing.. you should use an IGP protocol like OSPF..

and Advertise the Small network via OSPF.. this protocol will take care of your internal connectivity between your small network as well..


i.g. /routing ospf network add area=backbone network=x.y.z0/28 or /29

Also its will be help full if can draw your network diagram and send it here, will have better look on internal and external network connectivity layout with IP level..

Also I would suggest you to look at my presentation at Dubai MUM its will be help full for you to fix your issue..

http://mum.mikrotik.com/presentations/AE12/ali.pdf

good Luck

with my best regards
Ali.

Who is online

Users browsing this forum: No registered users and 9 guests