Load Balancing over Serial Line

[tzachi.slav]

Dear Experts,

I would like some help regarding Load Balancing.

Currently I have two sites. Each site has two routers connected VIA Ethernet. The sites are connected through one serial line (Drawing A - Current). I would like to add another Serial Line for resilience (Drawing B - Future).

Our network main routing protocol is EIGRP.

How can I implement load balancing over the suggested architecture?

I know that EIGRP support load balancing over equal costs. Is it valid for my scenario?

I was thinking of implementing HSRP. Is HSRP useful for this kind of architecture?

I hope you could help me.

Best Regards,

Tzachi Slav

[spremkumar]

HI Tzachi

I would suggest to take look on GLBP which may be best fit for your requirement.

GLBP will take care of load balancing as well as resilience without any additional config ..

do go thru this link for more info on GLBP..

http://www.cisco.com/en/US/products/ps6550/products_white_paper09186a00801541c8.shtml

regds

[amit-singh]

Hi,

I agree with Edwin on this and GLBP will be the good solution for you.

HTH,

-amit singh

amisin@gmail.com

[tzachi.slav]

Hi,

Thank you very much for your answers.

However, i am not sure that this is what i look for.

Currently, both routers use HSRP on their Ethernet interface.

I wanted to know, what the consequences of adding another serial line are.

For instance, take a look at the picture i have attached. Is router RC thinks that Serial AB1 / AB2 are one line according to your solution (That's what I would like to achieve by adding another serial line(?

I hope you understand my goals.

Tzachi Slav

[tzachi.slav]

Hi,

Thank you very much for your answers.

However, i am not sure that this is what i look for.

Currently, both routers use HSRP on their Ethernet interface.

I wanted to know, what the consequences of adding another serial line are.

For instance, take a look at the picture i have attached. Is router RC thinks that Serial AB1 / AB2 are one line according to your solution (That's what I would like to achieve by adding another serial line(?

I hope you understand my goals.

Tzachi Slav

[amit-singh · Accepted solution]

Hi Friend,

I have just gone thorugh the attachment that you have added and as per router C it will not be a single link to reach the other side destination. Router C will still learn two diiferent routes from both the links SAB1/AB2 and if EIGRP is doing equal cost=path/unequal cost-path load-balancing it will add both the routes to its routing table and by default will do per destination load-balancing. The LAn clients which are on LAN and you use the GLBP, it will be a single link for them.

If you implement HSRP then only one router can be active at one time and the other will be in stand-by state. If you use GLBP both the routers will be actively forwarding the traffic over both the serial links SAB1/AB2.

HTH

-amit singh

[Danilo Dy]

Use GLBP at the LAN, use default route in the WAN.