Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Community Member

OSPF Load Balancing

Hi expertise,

M having a LAB senario and using load balancing.As per load balancing active route should be rotate if destinaton are different(Fast Switchig).Is there any way to know, how my traffice routed.Basically i want to check path when m using fast switching as well as process switching

Thnaks & rgds

Ashish Singh

5 REPLIES

Re: OSPF Load Balancing

Hello Ashish,

the topic title of your post is related to OSPF load balancing, is that what your question is about ? Basically, in order to check the fast switching routing table, you can use the command:

show ip cache [prefix mask] [type number]

This will display the routing table cache used to fast switch IP traffic. For OSPF, the following applies:

If there are multiple routes to a network with the same route type and cost, it chooses all the routes to be installed in the routing table, and the router does equal cost load balancing across multiple paths.

Is that what you are looking for ?

Regards,

GNT

Community Member

Re: OSPF Load Balancing

Thanks 4 reply.

ya,quite the same thing .Let suppose m having 2 link with equal cost for same netwok,one of them will show active when type 'sh ip router a.b.c.d'.If m using process switching in that case packet should go through both link so how i can check that my both link equally utilize.Is there any command to check this thing.If m doing tracert or pinging to same network only one route show actvie.

Bronze

Re: OSPF Load Balancing

Hi,

use this debug command

debug ip packet

along with

show ip cache

HTH

Thanks

Raj

Re: OSPF Load Balancing

Hello,

supposed that you have both your equal cost routes installed in your routing table (which you can verify with the 'show ip route' command), the default load-balancing is per-destination, that is probably why you are seeing only one route actually being used. You can change that default behaviour, and configure your interfaces with the 'ip load-sharing per-packet' interface command. Be aware, though, that per-packet load sharing can have implications, too, such as out-of-sequence packets...

Regards,

GNT

Community Member

Re: OSPF Load Balancing

U r right, but ip load-sharing per packet works on ip cef, if m using "no ip route cache" then also m able to enable process swithcing. But in that case still m getting one route active.

Thanks & rgds..

Ashish Singh

200
Views
0
Helpful
5
Replies
CreatePlease to create content