Solved

CISCO Load Balancing CEF

Posted on 2014-09-26
4
298 Views
Last Modified: 2014-09-30
Hi,

I have a quick question on CEF.  Once I configure CEF on the 2 interfaces that will be going to out to the web, do I configure 2 last resort routes.  For Example:

0.0.0.0 0.0.0.0 192.168.1.1 1
0.0.0.0 0.0.0.0 192.168.1.2 1

Thank you for your help in advance
0
Comment
Question by:thomasm1948
  • 2
  • 2
4 Comments
 
LVL 14

Expert Comment

by:Otto_N
ID: 40348682
Short answer: Yes. If you have two gateways to the Internet, you should configure two static routes.

Technically, CEF and last-resort routes doesn't really have anything to do with each other - You would have configured both static routes in any case, whether you used  CEF or not.
0
 

Author Comment

by:thomasm1948
ID: 40350477
what would the benefit be, if I do not configure CEF.  Is there a better way to load balance between to ISPs?
0
 
LVL 14

Accepted Solution

by:
Otto_N earned 500 total points
ID: 40351861
CEF switching is just a way to speed up the rate at which packets are switched - It use up a bit more memory resources (to build the forwarding tables required), but if your device have sufficient memory, CEF is recommended - It is by default enabled on the newer Cisco kit.

I must confess, I had to read up on the load balancing of CEF. Without CEF, traffic is usually forwarded round-robin (one packet to ISP-1, the next packet to ISP-2).  CEF, by default, load-balance per destination.  This result in a more  intelligent forwarding - packets from the same source to the same destination will be switched to the same ISP, where packets from the same source to a different destination might be switched to the other ISP.

While this can give you uneven utilization between the two uplinks (depending on your traffic profile), it will reduce the probability that packets are delivered out-of-order.
0
 

Author Closing Comment

by:thomasm1948
ID: 40351969
thank you for all of your help
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Concerto Cloud Services, a provider of fully managed private, public and hybrid cloud solutions, announced today it was named to the 20 Coolest Cloud Infrastructure Vendors Of The 2017 Cloud  (http://www.concertocloud.com/about/in-the-news/2017/02/0…
This article will inform Clients about common and important expectations from the freelancers (Experts) who are looking at your Gig.
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're looking for how to monitor bandwidth using netflow or packet s…
Both in life and business – not all partnerships are created equal. Spend 30 short minutes with us to learn:   • Key questions to ask when considering a partnership to accelerate your business into the cloud • Pitfalls and mistakes other partners…

773 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question