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Community Member

Load sharing/Blancing and Redundance

Dear friends,

I have a secnario (attached) and the requirement is as below.

Im in need of Load sharing as well as load balancing (load should be shared between these two isps and if one link has gone another should takeover.

In LAN side I'm in need of redundancy as well as load sharing.Which one would be better GLBP or HSRP.

pls guide.



Re: Load sharing/Blancing and Redundance

Hi Rajeev,

unfortunately the attachement is missing.

But generally speaking GLBP will better serve your request for Load balancing and backup.

Basically your LAN client will use both physical routers playing default gateway.

Make sure traffic from one default gatewa is going to one ISP or at least session based, if NAT is involved.

There are already numerous posts covering those topics. So forum search might also help.

Other than that, please attach your network details if you need more detailed help!

Regards, Martin

Community Member

Re: Load sharing/Blancing and Redundance


GLBP would be best solution.


Re: Load sharing/Blancing and Redundance

Well do post your diagram, and also the show version of your router. Remember that in your GLBP your LAN has to be directly connected to your internet Routers. But i have a feeling that you might have a Firewall in between your LAN and router. In that case you cant use GLBP and have to go with HSRP with the tracking interface option.



Do rate if this helps :)

Re: Load sharing/Blancing and Redundance

1. WAN

1.1 In WAN side, if you plan to connect between two ISPs, you need to have your own AS and IP Address block from RIR plus your uplink should be different TELCO and you have two routers running BGP. With this setup, you achieve full redundancy in terms of TELCO, ISP, and router and also load sharing.

1.2 If you can't get your own AS and IP Address block from RIR. You can still achieve router redundancy, TELCO redundancy, load sharing but not ISP redundancy. You can connect to a single ISP with two uplink from different TELCO, get your ISP to connect these two uplinks to different routers in their side. Your ISP will then give you Private AS and minimum of two subnets/networks so that you can load share them between two uplinks.

2. LAN

With two routers mentioned in WAN, you should use GLBP so that your upload to WAN is load balance (depends on the GLBP configuration) while your download from WAN using BGP is load shared.

NOTE: I already did 1.2 and 2 for majority of setup. I also did 1.1 and 2 for some setup. 1.2 and 2 is attractive to small networks. 1.1 and 2 is for bigger networks which requires AS and IP Address block from RIR

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