Multihoming using single router

[vibipabraham]

As I am new to multihoming I would like to know whether it is possible to have dual ISP's connecting to one single Edge Router in a fail over ISP scenario. I will be connecting my firewall to the end router and the router will have two ISP's broadcasting the BGP routes.

[smehrnia]

Hi,

yes it is possible, if u r using bgp you'll be able to use bgp attributes (i.e. weight) to choose ur primary and backup route.

Hope it Helps,

Soroush.

[Sandeep Choudhary]

HI Vibi,

Yes you can do it.

Just check this page with sample configration:

http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a008009456d.shtml

Hope this is right documents for question ?

Regards

Please rate if it helps.

[Richard Burts]

Yes it is quite possible to multi home with 2 ISPs on a single router. In fact, in some ways it is easier to do on one router than to do on two routers.

One thing to be aware of when running BGP to multihome with multiple ISPs on one router is whether both ISP will send full routing table updates. It takes quite a bit of memory to have the entire table and if you receive the entire table from both providers then it increases the memory requirement for your router. Many people who multi home with have one (and sometimes have both) ISP to just advertise a default route or a default route and the routes that are directly connected to their AS. This can be a good strategy where one ISP is primary and the other ISP is intended for fail over.

HTH

Rick

[bava_ccna]

Yes, its relatively easy to do so but make sure to apply a filter to accept only default routes from both ISP if you don't want complete routes due to memory concern..

Pls rate the useful posts

-bava