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Multi-homed Internet connection - routes advertisements with BGP

Hi netpros,

I need to find out whether it is possible to peer with two ISPs for advertising a public range using different metrics. Also what about if the IP range ( let's say 203.203.203.0/28) does not belong to the customer but to ISP1. Can the ISPs provide a fail-over type of set up in that scenario ..? Apologise I am not very familiar with BGP and your response is much appreciated !!!

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Re: Multi-homed Internet connection - routes advertisements with

before you own the public IP range, you would need to have ur own AS number ( so no private AS).

When u have the above, u can then have 2 peering sessions and full redundancy from ISPs. in fact you can go further and decide which you wish to have as primary, and which woudl be ur backup.

HTH

Sam

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Re: Multi-homed Internet connection - routes advertisements with

you control BGP, so you can advertise it anyway you see fit. However you need to agree with your ISP on certain things and parameters.

If you are trying to achieve primary and backup set up, you could fine tune AS_PATH attributes.

if ISP1 owns 203.203.203.0/28 only ISP1 can advertise this prefix to the internet. and ISP2 will advertise its own network assigned to the customer. This is a problem when redundancy needs to be achieved.

the typical set up, is that the customer owns the public IP range and therefore both ISPs can advertise it, achieving 1st step to redundancy in this manner.

pls rate all helpful posts

Sam

Re: Multi-homed Internet connection - routes advertisements with

Great info Sam .. thanks !!!

Ok let's say that the customer owns the IP range. Could I peer with both ISPs using two private AS and advertise that range with different metrics. and then the ISPs can redistribute this range onto the Public AS. Is that feasible ..? so that I don't have to use a public AS to peer with them.

Your comments are much appreciated !!!

Re: Multi-homed Internet connection - routes advertisements with

before you own the public IP range, you would need to have ur own AS number ( so no private AS).

When u have the above, u can then have 2 peering sessions and full redundancy from ISPs. in fact you can go further and decide which you wish to have as primary, and which woudl be ur backup.

HTH

Sam

Re: Multi-homed Internet connection - routes advertisements with

Cheers Sam,

Understand now .. your input is exactly what I was looking for .. thanks heaps !!!

New Member

Re: Multi-homed Internet connection - routes advertisements with

We are also in the process of becomming dual homed with two different ISP. Sam is correct, you will need your own AS number. The process with ARIN was very smooth and simple.

Just as an FYI.. Both of our ISPs had a "dual homed" document we filled out informing them of all the AS numbers involved. May want to check and make sure yours do not have the same requirement.

Brent

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