Load Balance between 2 Cisco 3750 switches with equal-cost paths

Unanswered Question
Jan 17th, 2012
User Badges:

Hi,

I have two offices in rural area with a quite distance between them. Offices are connected with private wireless 100Mbps and cooper 100Mbps links provided by different ISP. Wireless connections are delivered as a private L3 Ethernet link but cooper as private L2 Ethernet trunk link. In both offices I have Cisco 3750 L3 switches. I would like to use both link (equal-cost paths) in load balanced configuration but not sure how. Both switches running EIGRP. Asymmetric routing is not an option. Per-destination load-balancing or something else?

Any help is appreciate

Thanks

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
Joseph W. Doherty Tue, 01/17/2012 - 18:07
User Badges:
  • Super Bronze, 10000 points or more

Disclaimer


The   Author of this posting offers the information contained within this   posting without consideration and with the reader's understanding that   there's no implied or expressed suitability or fitness for any purpose.   Information provided is for informational purposes only and should not   be construed as rendering professional advice of any kind. Usage of  this  posting's information is solely at reader's own risk.


Liability Disclaimer


In   no event shall Author be liable for any damages whatsoever (including,   without limitation, damages for loss of use, data or profit) arising  out  of the use or inability to use the posting's information even if  Author  has been advised of the possibility of such damage.


Posting


Not quite sure how you avoid asymmetrical routing when load balancing.  Could you clarify this requirement?

wilson.jr Wed, 01/18/2012 - 08:12
User Badges:

I'll be sending voice traffic via these links. Can somehow load balancing be symmetric or do I have any other solution to aggregate these two links?

Jeff Van Houten Tue, 01/17/2012 - 19:16
User Badges:
  • Silver, 250 points or more

could you route the copper Ethernet link? If so you could adjust the metrics to be equal cost at which point load balancing would be automatic.


Sent from Cisco Technical Support iPad App

rizwanr74 Wed, 01/18/2012 - 08:54
User Badges:
  • Gold, 750 points or more

If on both link cost are equal (as per EIGRP resulted metric from both links) then EIGRP will do load-balancing by default.

However if both links cost are resulted in not equal metrics, then you can enable unequal cost load-balancing, please follow the Cisco documentation.


http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a008009437d.shtml




I assume this is how your offices are connected.


               |-------wireless------ |           __  

| Office A  |                          | Office B |

|               |______wired____|             |

Thanks

Rizwan Rafeek

paolo bevilacqua Wed, 01/18/2012 - 09:38
User Badges:
  • Super Gold, 25000 points or more
  • Hall of Fame,

    Founding Member

I don't think that 3750 switches can do unequal cost load balacing.

One would need a true router for that, an is not a good idea anyway.

Actions

This Discussion