Community discussions

MikroTik App
 
doush
Long time Member
Long time Member
Topic Author
Posts: 665
Joined: Thu Jun 04, 2009 3:11 pm

OSPF Load Balance

Fri Oct 11, 2013 1:30 am

I have a problem.

We have 2 uplinks to a router. OSPF is running. 1st uplink is 3 hops, and 2nd uplink is a direct PtP link (1 hop)

We would like to have the incoming traffic being distrubuted among the links. It is NOT necessary to be %100 equal but just like what we do with ECMP (2 gateways to same destination)

Unfortunately OSPF chooses the SHORTEST path (which is the 2nd uplink) to the router and the other uplink becomes completely idle while the 2nd link has all the traffic.

Do you have any solutions to this problem ?

I appreciate any help.
 
doush
Long time Member
Long time Member
Topic Author
Posts: 665
Joined: Thu Jun 04, 2009 3:11 pm

Re: OSPF Load Balance

Fri Oct 11, 2013 1:37 pm

Anyone ?
 
Davs
just joined
Posts: 2
Joined: Fri Oct 11, 2013 12:44 pm

Re: OSPF Load Balance

Fri Oct 11, 2013 1:51 pm

I'm just guessing here, but what if you would set the cost of that direct route to the same as the other route is (i'm guessing 30)?
 
doush
Long time Member
Long time Member
Topic Author
Posts: 665
Joined: Thu Jun 04, 2009 3:11 pm

Re: OSPF Load Balance

Sat Oct 12, 2013 3:21 pm

Whatever I do, I see only a single gateway (which is the one with a single hop) on the upstream router. The other 3 hop route to this specific router dissapears.
So basically,on the upstream router, there becomes only a single gateway to this router although it has to be 2 gateways.

Any other solutions ?
Mikrotik ?
 
djdrastic
Member
Member
Posts: 367
Joined: Wed Aug 01, 2012 2:14 pm

Re: OSPF Load Balance

Mon Oct 14, 2013 8:20 am

Are these routes getting redistributed in via connected or static ?Are they default or static routes and if so are you type 1 or type 2 importing them ? I had done something similar to this for a client (one vlan) to a wireless p2p and another 2 hop DSL Router) eons ago , and I think all I had to do was adjust the costing to be the same in both OSPF and Native IP Routing.
 
doush
Long time Member
Long time Member
Topic Author
Posts: 665
Joined: Thu Jun 04, 2009 3:11 pm

Re: OSPF Load Balance

Mon Oct 14, 2013 4:56 pm

they are distrubuting connected routes (PPPoE clients)
They are type 2

when I run the OSPF on the 1 hop link, the other route (3 hop ) dissapears in the upstream router.

I only see 1 gateway to the subnets on this router instead of 2 subnets.
 
User avatar
StubArea51
Trainer
Trainer
Posts: 1739
Joined: Fri Aug 10, 2012 6:46 am
Location: stubarea51.net
Contact:

Re: OSPF Load Balance

Tue Oct 15, 2013 11:58 am

OSPF chooses the lowest cost path. The simplest way to fix it is to increase the cost of the single link path to be higher than the multiple link path. If you want ECMP, then equalize the cost between the paths.

BGP is a much better tool to do this...I would highly recommend reviewing this presentation from USA MUM 2013

http://mum.mikrotik.com/presentations/US13/kevin.pdf

Who is online

Users browsing this forum: mrtrca and 24 guests